• TABLE OF CONTENTS
HIDE
 Title Page
 How to use this soil survey
 Table of Contents
 Index to soil mapping units
 Summary of tables
 Foreword
 General nature of the area
 How this survey was made
 General soil map for broad land...
 Soils maps for detailed planni...
 Use and management of the...
 Soil properties
 Classification of soils
 Formation of the soils
 Illustrations
 Tables
 General soil map
 Index to map
 Map






Title: Soil survey of San Juan area of Puerto Rico
CITATION PAGE IMAGE ZOOMABLE
Full Citation
STANDARD VIEW MARC VIEW
Permanent Link: http://ufdc.ufl.edu/UF00027410/00001
 Material Information
Title: Soil survey of San Juan area of Puerto Rico
Physical Description: x, 141 p., 66 fold. p. of plates : ill., maps ; 29 cm.
Language: English
Creator: Boccheciamp, Rafael A
United States -- Soil Conservation Service
Puerto Rico -- Federal Experiment Station, Mayaquez
Publisher: Dept. of Agriculture, Soil Conservation Service
Place of Publication: Washington
Publication Date: 1978
 Subjects
Subject: Soils -- Maps -- Puerto Rico -- San Juan   ( lcsh )
Genre: federal government publication   ( marcgt )
bibliography   ( marcgt )
non-fiction   ( marcgt )
 Notes
Bibliography: Bibliography: p. 68.
Statement of Responsibility: by Rafael A. Boccheciamp.
General Note: Prepared in cooperation with University of Puerto Rico, Agricultural Experiment Station.
General Note: Issued Nov. 1977.
 Record Information
Bibliographic ID: UF00027410
Volume ID: VID00001
Source Institution: University of Florida
Rights Management: All rights reserved by the source institution and holding location.
Resource Identifier: aleph - 001198227
oclc - 04617717
notis - AFU8468

Table of Contents
    Title Page
        Title
    How to use this soil survey
        Page ia
        Page ib
        ii
    Table of Contents
        Page iii
        Page iv
    Index to soil mapping units
        Page v
        Page vi
    Summary of tables
        Page vii
        Page viii
    Foreword
        Unnumbered ( 11 )
        Unnumbered ( 12 )
    General nature of the area
        Page 1
        Climate
            Page 1
    How this survey was made
        Page 2
    General soil map for broad land use planning
        Page 2
        Map unit descriptions
            Page 3
        Soils formed in residuum from basic volcanic rocks
            Page 3
            Maricao-Los Guineos
                Page 3
            Humatas-Naranjito-Consumo
                Page 3
            Mucara-Caguabo
                Page 4
            Descalabrado
                Page 4
        Soils formed in residuum from intrusive igneous rocks
            Page 4
            Pandura-Lirios
                Page 4
        Soils formed in residuum from limestone
            Page 5
            Tanama-Colinas-Soller
                Page 5
        Soils formed in transported materials
            Page 5
            Almirante-Vega Alta-Matanzas
                Page 5
            Toa-Bajura-Coloso
                Page 5
            Mabi-Rio Arriba
                Page 6
            Martin Pena-Saladar-Hydraquents
                Page 6
    Soils maps for detailed planning
        Page 6
        Soil descriptions
            Page 7
            Page 8
            Page 9
            Page 10
            Page 11
            Page 12
            Page 13
            Page 14
            Page 15
            Page 16
            Page 17
            Page 18
            Page 19
            Page 20
            Page 21
            Page 22
            Page 23
            Page 24
            Page 25
            Page 26
            Page 27
            Page 28
            Page 29
            Page 30
            Page 31
            Page 32
            Page 33
            Page 34
            Page 35
    Use and management of the soils
        Page 36
        Crops and pasture
            Page 36
            Yields per acre
                Page 37
            Capability classes and subclasses
                Page 38
        Woodland
            Page 38
            Woodland management and productivity
                Page 39
        Engineering
            Page 39
            Building site development
                Page 40
            Sanitary facilities
                Page 41
            Construction materials
                Page 42
            Water management
                Page 42
            Recreation
                Page 43
    Soil properties
        Page 43
        Engineering properties
            Page 44
        Physical and chemical properties
            Page 44
        Soil and water features
            Page 45
    Classification of soils
        Page 46
        Soil series and morphology
            Page 46
            Aceitunas series
                Page 46
            Albonito series
                Page 46
            Almirante series
                Page 47
            Bajura series
                Page 47
            Bayamon series
                Page 47
            Caguabo series
                Page 48
            Candelero series
                Page 48
            Catalina series
                Page 49
            Catano series
                Page 49
            Cayagua series
                Page 49
            Colinas series
                Page 50
            Coloso series
                Page 50
            Consumo series
                Page 50
            Corozal series
                Page 51
            Daguey series
                Page 51
            Descalabrado series
                Page 52
            Dique series
                Page 52
            Guayama series
                Page 53
            Humacao series
                Page 53
            Humatas series
                Page 53
            Jagueyes series
                Page 54
            Juncal series
                Page 54
            Juncos series
                Page 55
            Lares series
                Page 55
            Limones series
                Page 56
            Lirios series
                Page 56
            Mabi series
                Page 57
            Malaya series
                Page 57
            Maricao series
                Page 58
            Martin Pena series
                Page 58
            Matanzas series
                Page 58
            Montegrande series
                Page 59
            Morado series
                Page 59
            Mucara series
                Page 59
            Naranjito series
                Page 60
            Pandura series
                Page 60
            Pellejas series
                Page 60
            Reilly series
                Page 61
            Rio Arriba series
                Page 61
            Rio Piedras series
                Page 61
            Sabana series
                Page 62
            Sabana seca series
                Page 62
            Saladar series
                Page 63
            Soller series
                Page 63
            Tanama series
                Page 63
            Toa series
                Page 63
            Torres series
                Page 64
            Vega Alta series
                Page 64
            Vega Baja series
                Page 65
            Via series
                Page 65
            Vivi series
                Page 65
            Yunes series
                Page 66
        Classification
            Page 66
    Formation of the soils
        Page 67
        Factors of soil formation
            Page 67
            Parents of soil formation
                Page 67
            Climate
                Page 67
            Plants and animals
                Page 67
            Relief
                Page 68
            Time
                Page 68
                Page 69
                Page 70
                Page 71
                Page 72
    Illustrations
        Page 73
        Page 74
        Page 75
        Page 76
        Page 77
        Page 78
        Page 79
        Page 80
        Page 81
        Page 82
    Tables
        Page 83
        Page 84
        Page 85
        Page 86
        Page 87
        Page 88
        Page 89
        Page 90
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        Page 134
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        Page 136
        Page 137
        Page 138
        Page 139
        Page 140
    General soil map
        Page 141
        Page 142
    Index to map
        Page 143
    Map
        Page 1
        Page 2
        Page 3
        Page 4
        Page 5
        Page 6
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Full Text

/) S7. CK :: '
SOIL SURVEY OF

San Juan Area of Puerto Rico


United States Department of Agriculture
Soil Conservation Service
In cooperation with
University of Puerto Rico
Agricultural Experiment Station


A
^^a~rk"





HOW TO U


Locate your area of interest on
the "Index to Map Sheets" (the
last page of this publication).






i -, f'.- I z '.."7_ -
r, I1, j_._---~--____'. ,,_!








Locate your area of interest
3* on the map sheet.


List the mapping unit symbols
4. that are in your area.


S Note the number of the map
S sheet and turn to that sheet.


Fa
Bac


VaaF
Ba(-t -


A7-B
AsB /
/Ce


Symbols


,AsB
-BaC
-Ce
-Fa
-Ha
SWaF


-


~al II Y~a


--








IS SOIL SURVEY





Turn to "Index to Soil Mapping Units"

which lists the name of each mapping unit and the

page where that mapping unit is described.


See "Summary of Tables" followo

Contents) for location of addition

on a specific soil use.


wing Lthe

anal data ....-











r C-Z I ~


Consult "Contents" for parts of the publication that will meet your specific needs.

This survey contains useful information for farmers or ranchers, foresters or

agronomists; for planners, community decision makers, engineers, developers,

builders, or homebuyers; for conservationists, recreationists, teachers, or

students; to specialists in wildlife management, waste disposal, or pollution control.


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This is a publication of the National Cooperative Soil Survey, a joint effort
of the United States Department of Agriculture and agencies of the States,
usually the Agricultural Experiment Stations. In some surveys, other Federal
and local agencies also contribute. The Soil Conservation Service has leader-
ship for the Federal part of the National Cooperative Soil Survey. In line with
Department of Agriculture policies, benefits of this program are available to
all, regardless of race, color, national origin, sex, religion, marital status, or age.
Major fieldwork for this soil survey was completed in October 1972. Soil
names and descriptions were approved in August 1973. Unless otherwise in-
dicated, statements in the publication refer to conditions in the survey area in
1976. This survey was made cooperatively by the Soil Conservation Service
and the University of Puerto Rico Agricultural Experiment Station. It is part
of the technical assistance furnished to the Cibuco, San Juan, Torito, Torrecil-
las and Turabo Soil Conservation Districts.
Soil maps in this survey may be copied without permission, but any enlarge-
ment of these maps can cause misunderstanding of the detail of mapping and
result in erroneous interpretations. Enlarged maps do not show small areas of
contrasting soils that could have been shown at a larger mapping scale.










Cover: Contour plantings of bananas in the San Juan Area.










Contents


Page
Index to soil mapping units........................................ v
Summary of tables .................................................. vii
F orew ord ........................................................................ ix
General nature of the area............................................ 1
Clim ate ....................................................................... 1
S How this survey was made.................................... 2
General soil map for broad land use planning........ 2
Map unit descriptions ............................................ 3
Soils formed in residuum from basic volcanic
rocks ..................................... ......................... 3
1. Maricao-Los Guineos.................................. 3
2. Humatas-Naranjito-Consumo ........................ 3
3. Mucara-Caguabo .............................................. 4
4. Descalabrado .................................................. 4
Soils formed in residuum from intrusive
igneous rocks.................................................. 4
5. Pandura-Lirios ............................................... 4
Soils formed in residuum from limestone ............ 5
6. Tanama-Colinas-Soller ..................................... 5
Soils formed in transported materials ................ 5
7. Almirante-Vega Alta-Matanzas .................... 5
8. Toa-Bajura-Coloso.......................................... 5
9. Mabi-Rio Arriba............................................. 6
10. Martin Pena-Saladar-Hydraquents .............. 6
Soil maps for detailed planning ................................ 6
Soil descriptions ......................................................... 7-
Use and management of the soils ............................ 361-
Crops and pasture .................................... 36
Yields per acre ..................................................... 37
Capability classes and subclasses ...................... 38
Woodland ........................................................................ 38
Woodland management and productivity ............ 39
E ngineering................................ .................... ..... 39
Building site development ................................. 40
Sanitary facilities .................................................... 41
Construction materials ............................................ 42
Water management ................................. .... 42
Recreation ............................................................. 43
Soil properties ............................................................... 43
Engineering properties ........................................... 44
Physical and chemical properties ............................ 44
Soil and water features............................................ 45
Classification of soils ................................................ .. 46
Soil series and morphology............................. ...... 46
Aceitunas series ................................... ......... 46
Aibonito series ....................................... ........... 46
Almirante series .................................... ............ 47
Bajura series .......................................... .......... 47
Bayamon series..................................... ........... 47
Caguabo series ....................................................... 48
Candelero series ................................................ 48
Catalina series.................... ........................... 49
Catano series............................................................ 49


Cayagua series .................................. ............
Colinas series ................................... ... ....
Coloso series ...................................... ...............
Consumo series ................................. ..............
Corozal series .................................. ...............
Daguey series ................................ ...............
Descalabrado series .........................................
D ique series........................................................
Durados series ................................. .............
Estacion series .................................. ..............
Guayama series.................................................
Humacao series....................................................
Humatas series .................................. .............
Jagueyes series ................................... .............
Juncal series ................................. ...............
Juncos series .................................. ...............
Lares series.................................. ...............
Limones series ................................. ............
L irios series............................................... .....
Los Guineos series ............................................
Mabi series..................:......................................
M alaya series........................................ ................
Maricao series ............................................
Martin Pena series...........................................
Matanzas series............................ ........
Montegrande series ..........................................
Morado series ................................... ............
Mucara series .................................... .....
Naranjito series ................................. ............
Pandura series ................................. .............
Pellejas series ................................... ............
R eilly series............................................. .............
Rio Arriba series .............................................
Rio Piedras series ......................................
Sabana series.......................................................
Sabana Seca series ....................................................
Saladar series ...................................................
Soller series.............................. ... ...............
Tanama series .................................. ..............
Toa series..............................................................
Torres series ......................................................
Vega Alta series................................... ...........
Vega Baja series.................................. .............
Via series .................................................. ......
Vivi series ................................... ........
Yunes series ................................... .......
Classification .......................................... ...............
Formation of the soils.............................................
Factors of soil formation ......................................
Parent material............................ ..............
Climate ........................................................ .......
Plants and animals .................................... ......
R relief ................................................... .................







Contents-continued
Page
T im e ............................................................................ 68
References............................................. .................. 68
Glossary............................................................................ 68
Illustrations .............................................................. 73
Tables ........................................................................... 83

Issued November 1978










Index to soil mapping units


Page
AaB-Aceitunas clay, 2 to 5 percent slopes ................ 7
AaC-Aceitunas clay, 5 to 12 percent slopes.............. 7
AbD-Aibonito clay, 12 to 20 percent slopes ........... 7
AbE-Aibonito clay, 20 to 40 percent slopes ........... 8
AmB-Almirante clay, 2 to 5 percent slopes .............. 8
AmC-Almirante clay, 5 to 12 percent slopes .......... 8
Ba-Bajura clay .......................................... 9
BmB-Bayamon clay, 2 to 5 percent slopes ................ 9
CaE-Caguabo clay loam, 20 to 40 percent slopes .... 9
CaF-Caguabo clay loam, 40 to 60 percent slopes .... 10
CbF-Caguabo-Rock outcrop complex, 40 to 60
percent slopes .................................. ............ 10
Ce-Candelero loam ....................................... 10
1CC-Catalina clay, 4 to 12 percent slopes ................ 11
Cn-Catano loamy sand ..................................... 11
Co-Cayagua sandy loam ........................................ 11
CrD2-Colinas clay loam, 12 to 20 percent slopes,
eroded .......................................... ............... 11
CrE2-Colinas clay loam, 20 to 40 percent slopes,
eroded ............................................... ................... 12
CrF2-Colinas clay loam, 40 to 60 percent slopes,
eroded ....................................... ........................ 12
Cs- Coloso silty clay loam .......................... ... .......... 12
CuE-Consumo clay, 20 to 40 percent slopes.............. 13
CuF-Consumo clay, 40 to 60 percent slopes.............. 13
CzC-Corozal clay, 5 to 12 percent slopes .................. 14
DaC-Daguey clay, 2 to 12 percent slopes .................. 14
DaD-Daguey clay, 12 to 20 percent slopes .............. 14
DeF-Descalabrado clay loam, 40 to 60 percent
slopes ................................................... .............. 15
DgF-Descalabrado-Rock outcrop complex, 40 to 60
percent slopes ..................................... ........ 15
Dm- Dique loam ..................................................... 15
Dr- Durados sandy loam ........................................... 15
Es- Estacion silty clay loam ....................................... 16
GuF-Guayama clay loam, 20 to 60 percent slopes.... 16
Hm-Humacao loam ................................. ... .... 16
HtE-Humatas clay, 20 to 40 percent slopes.............. 16
HtF-Humatas clay, 40 to 60 percent slopes........... 17
HuF-Humatas-Rock outcrop complex, 20 to 60
percent slopes .................................... ....... ........... 17
Hy-Hydraquents, saline ....................................... 18
JaE2-Jagueyes loam, 20 to 40 percent slopes,
eroded .......................................... ... ........ .. 18
JnD2-Juncal clay, 5 to 20 percent slopes, eroded .... 18
JuC-Juncos clay, 5 to 12 percent slopes .................. 18
JuD-Juncos clay, 12 to 20 percent slopes ................. 19
LaB-Lares clay, 2 to 5 percent slopes.................. 19
LaC2-Lares clay, 5 to 12 percent slopes, eroded...... 19
LmE-Limones clay, 20 to 40 percent slopes............ 20
LmF-Limones clay, 40 to 60 percent slopes.............. 20
LoF2-Lirios silty clay loam, 20 to 60 percent
slopes, eroded ............................................. ..... 21


Page
LsE-Los Guineos clay, 20 to 40 percent slopes........ 21
LsF-Los Guineos clay, 40 to 60 percent slopes ........ 21
MaA-Mabi clay, 0 to 2 percent slopes ................... 22
MaB-Mabi clay, 2 to 5 percent slopes ................. 22
MaC-Mabi clay, 5 to 12 percent slopes ................ 22
Md- Made land........................................ .......... 22
M1F-Malaya clay loam, 40 to 60 percent slopes........ 23
MoF-Maricao clay, 20 to 60 percent slopes................ 23
Mp- Martin Pena muck .............................................. 23
MsB-Matanzas clay, 2 to 5 percent slopes ................ 23
MtB-Montegrande clay, 2 to 5 percent slopes .......... 24
MtC-Montegrande clay, 5 to 12 percent slopes ........ 24
MuF2-Morado clay loam, 40 to 60 percent slopes,
eroded .......................................................... 24
MxD-Mucara clay, 12 to 20 percent slopes.............. 25
MxE-Mucara clay, 20 to 40 percent slopes................ 25
MxF-Mucara clay, 40 to 60 percent slopes ............... 25
NaD2-Naranjito silty clay loam, 12 to 20 percent
slopes, eroded ...................... ...................................... 26
NaE2-Naranjito silty clay loam, 20 to 40 percent
slopes, eroded ................................... ............ 26
NaF2-Naranjito silty clay loam, 40 to 60 percent
slopes, eroded .............................. ........... 27
PaD-Pandura sandy loam, 12 to 20 percent slopes.. 27
PaE-Pandura sandy loam, 20 to 40 percent slopes.. 27
PaF-Pandura sandy loam, 40 to 60 percent slopes.. 28
PeF-Pellejas clay loam, 40 to 60 percent slopes ...... 28
-- Re-Reilly sandy loam ........................... ...... 29
RoB-Rio Arriba clay, 2 to 5 percent slopes .............. 29
RoC2-Rio Arriba clay, 5 to 12 percent slopes,
eroded...................................... ......... 29
RpD2-Rio Piedras clay, 12 to 20 percent slopes,
eroded ................................... .............. 29
RpE2-Rio Piedras clay, 20 to 40 percent slopes,
eroded .................................................... 30
RpF2-Rio Piedras clay, 40 to 60 percent slopes,
eroded ................ .......................... ......... 30
SaF-Sabana silty clay loam, 40 to 60 percent
slopes ............................. ............. ......... 30
ScB-Sabana Seca clay, 2 to 8 percent slopes ........... 31
Sm Saladar m uck............................... ..................... 31
SoE-Soller clay loam, 20 to 40 percent slopes ......... 31
SoF-Soller clay loam, 40 to 60 percent slopes .......... 32
TaF-Tanama-Rock outcrop complex, 20 to 60
percent slopes ...................................... ......... .. 32
To- Toa silty clay loam................................ ........... 32
TrB-Torres loamy sand, 2 to 5 percent slopes........ 33
Ts-Tropopsamments ............................................ 33
Ud-Urban land-Durados complex............................ 33
Um-Urban land-Mucara complex .......................... 33
Us-Urban land-Sabana Seca complex .................... 33
Uv-Urban land-Vega Alta complex ........................ 33
VaB-Vega Alta clay loam, 2 to 5 percent slopes...... 34







Index to soil mapping units-continued
Page
VaC2-Vega Alta clay loam, 5 to 12 percent slopes,
eroded ......................................................... 34
\ Vg-Vega Baja silty clay ......................................... 34
VkC2-Via clay loam, 5 to 12 percent slopes, eroded 34
Vv- Vivi loam ........................................................... 35
YeE-Yunes silty clay loam, 20 to 40 percent slopes 35
YeF-Yunes silty clay loam, 40 to 60 percent slopes 35















Summary of Tables


Page
Acreage and proportionate extent of the soils (Table 4)............................. 87
Acres. Percent.
Building site development (Table 8) .......................................................... 96
Shallow excavations. Dwellings without basements.
Small commercial buildings. Local roads and
streets.
Capability classes and subclasses (Table 6) ...................................... ....... 92
Class. Total acreage. Major management concerns
(Subclass)-Erosion (e), Wetness (w), Soil problem
(s).
Classification of the soils (Table 16) ................................................................ 141
Soil name. Family or higher taxonomic class.
Construction materials (Table 10) ...................................................................... 109
Roadfill. Sand. Gravel. Topsoil.
Engineering properties and classifications (Table 13).................................. 126
Depth. USDA texture. Classification- Unified,
AASHTO. Fragments greater than 3 inches. Per-
centage passing sieve number-4, 10, 40, 200. Liquid
limit. Plasticity index.
Physical and chemical properties of soils (Table 14) .................................... 132
Depth. Permeability. Available water capacity. Soil
reaction. Shrink-swell potential. Risk of corro-
sion-Uncoated steel, Concrete. Erosion factors-K,
T.
Recreational development (Table 12) .............................................................. 120
Camp areas. Picnic areas. Playgrounds. Paths and
trails.
Sanitary facilities (Table 9) .................................................................................. 102
Septic tank absorption fields. Sewage lagoon areas.
Trench sanitary landfill. Area sanitary landfill.
Daily cover for landfill.
Soil and water features (Table 15)..................................... .............................. 137
Hydrologic group. Flooding-Frequency, Duration,
Months. High water table-Depth, Kind, Months.
Bedrock-Depth, Hardness. Subsidence-Initial,
Total.
Map units and their potential and limitations for specified use
(T able 3)........................ ........................................................................ ........... 86
Extent of area. Cultivated farm crops. Specialty
crops. Woodland. Urban uses. Intensive recreation
areas. Extensive recreation areas.








Summary of Tables-Continued


Page
Temperature and precipitation data (Tables 1 and 2) .................................. 84
Month. Temperature-Average daily maximum,
Average daily minimum, Average daily, Average
number of growing degree days. Precipita-
tion-Average, Average number of days with 0.10
inch or more, Average snowfall.
W ater manager ent (Table 11) ........................................................................... 115
Pond reservoir areas. Embankments, dikes, and
levees. Drainage. Terraces and diversions. Grassed
waterways.
Woodland management and productivity (Table 7) ...................................... 93
Ordination symbol. Management concerns-Erosion
hazard, Equipment limitation, Seedling mortality.
Potential productivity-Important trees. Trees to
plant.
Yields per acre of crops and pasture (Table 5).............................................. 89
Sugarcane, 18 month. Sugarcane, spring. Sugarcane,
ratoon. Plantains. Coffee. Pangolagrass. Merker
grass.















Foreword


The Soil Survey of the San Juan Area contains much information useful in
any land-planning program. Of prime importance are the predictions of soil
behavior for selected land uses. Also highlighted are limitations or hazards to
land uses that are inherent in the soil, improvements needed to overcome these
limitations, and the impact that selected land uses will have on the environ-
ment.
This soil survey has been prepared for many different users. Farmers,
ranchers, foresters, and agronomists can use it to determine the potential of
the soil and the management practices required for food and fiber production.
Planners, community officials, engineers, developers, builders, and homebuyers
can use it to plan land use, select sites for construction, develop soil resources,
or identify any special practices that may be needed to insure proper per-
formance. Conservationists, teachers, students, and specialists in recreation,
wildlife management, waste disposal, and pollution control can use the soil sur-
vey to help them understand, protect, and enhance the environment.
Great differences in soil properties can occur even within short distances.
Soils may be seasonally wet or subject to flooding. They may be shallow to
bedrock. They may be too unstable to be used as a foundation for buildings or
roads. Very clayey or wet soils are poorly suited to septic tank absorption
fields. A high water table makes a soil poorly suited to basements or un-
derground installations.
These and many other soil properties that affect land use are described in
this soil survey. Broad areas of soils are shown on the general soil map; the lo-
cation of each kind of soil is shown on detailed soil maps. Each kind of soil in
the survey area is described, and much information is given about each soil for
specific uses. Additional information or assistance in using this publication can
be obtained from the local office of the Soil Conservation Service or the
Cooperative Extension Service.
This soil survey can be useful in the conservation, development, and
productive use of soil, water, and other resources.








Angel Quintero
Director, Caribbean Area
Soil Conservation Service













State Agricultural Experiment Station


I DESECHEO T 30 M'LC> 1- .


AIL: I FAJARDO MON
70 I CULEBRA

MAYAGUEZ




PONCE









I MONA


Location of San Juan Area of Puerto Rico.








SOIL SURVEY OF SAN JUAN AREA OF PUERTO RICO


By Rafael A. Boccheciamp, Soil Conservation Service

Fieldwork by Rafael A. Boccheciamp, William Francia Rivera, Julio E. Trigo,
G. Torres Ricci, Jose E. Brunet, and Luis H. Rivera,
Soil Conservation Service

United States Department of Agriculture, Soil Conservation Service, in
cooperation with the University of Puerto Rico,
Agricultural Experiment Station


General nature of the area
The island of Puerto Rico is the smallest and farthest
east of the four islands Cuba, Jamaica, Hispaniola, and
Puerto Rico known as the Greater Antilles. It lies in the
Torrid Zone. The north central coast of Puerto Rico is
about 1,600 statute miles southeast of New York City,
and the western part of the island is about 450 miles from
the eastern point of Cuba. Ponce, on the south coast, is
about 525 miles due north of Caracas, Venezuela.
The island was discovered by Christopher Columbus on
his second voyage, November 19, 1493. The native inhabi-
tants of the island, the friendly Taino Indians of the
Arawak culture, lived in small villages, each ruled by a
cacique, a chief. They grew food crops such as cassava
and corn, and also tobacco and cotton. They also fished
and hunted birds for their subsistence. They were clever
at working stones, clay, and gold and adorned themselves
with ornaments of these materials. The island was first
settled in 1508 by Juan Ponce de Leon.
The San Juan Soil Survey Area is in northeast-central
Puerto Rico (see facing page). It is bounded on the north
by the Atlantic Ocean. San Juan, the capital of Puerto
Rico, is in the northern part of the survey area.
Mayaguez is 98 miles from San Juan. Ponce, the second
largest city on the island, is 75 miles from the capital. The
survey area covers an area of 447,279 acres. According to
the census of 1970, the population totaled 1,172,609, of
which 286,906 was rural and 885,703 urban. At that time
there were 8,646 farms in the survey area.
The area consists of three major physiographic areas:
the nearly level to sloping coastal plain, which is 10 per-
cent of the area; the haystacks or limestone hills with
their remarkable karst topography, which is about 4 per-
cent; and the extensive igneous upland, which is 86 per-
cent.
There are five soil conservation districts in the San
Juan Soil Survey Area, namely: the Cibuco SCD, 80,101
acres, the municipalities of Corozal, Comerio, Naranjito,
and Toa Alta; the San Juan SCD, 122,372 acres, the mu-
nicipalities of Bayamon, Dorado, Toa Baja, Catano,


Guaynabo, Rio Piedras, and Trujillo Alto; the Torito SCD,
74,533 acres, the municipalities of Cayey, Cidra, and
Aguas Buenas; the Turabo SCD, 88,643 acres, the mu-
nicipalities of Caguas, Gurabo, and San Lorenzo; and the
Torrecillas SCD, 81,630 acres, the municipalities of Bar-
ranquitas, Aibonito, and Orocovis.
Farming is the principal enterprise of the area. Nu-
merous industries, among which is the Consolidated Cigar
Company, the largest cigar factory in the world, con-
tribute to the welfare and economy of the island.
Improved pasture such as pangolagrass, stargrass, and
Merker grass cover about 210,750 acres, or 47 percent of
the area, according to the census of Agriculture of 1969.
Most of the pastureland is used for raising beef and dairy
cattle.
The principal cash and food crops of the area are plan-
tains, taniers, yams, and tobacco. The total acreage is
89,353, or 20 percent of the area.
Woodland covers 72,239 acres, or 16 percent of the sur-
vey area.

Climate

In the San Juan Area of Puerto Rico the days are hot,
except in January and February. The nights are warm all
year. Winds from the Atlantic Ocean lower the afternoon
temperatures on most days. Temperatures in the moun-
tains of the interior are appreciably lower than elsewhere,
but freezing temperatures are unknown anywhere in the
area. Rainfall is abundant throughout the year in most of
the area. The least falls in February and March. Except
for the semiarid southernmost part, rainfall is heaviest in
the mountains.
Tables 1 and 2 list data on temperature and precipita-
tion for the survey area, as recorded at San Juan Airport
for the period 1955 to 1974 and at Barranquitas, which is
2200 feet higher than San Juan, for the period 1963 to
1974.
In winter the average temperature at San Juan is 77
degrees F, and the average daily minimum temperature is
70.-The lowest temperature on record, which occurred at








SOIL SURVEY OF SAN JUAN AREA OF PUERTO RICO


By Rafael A. Boccheciamp, Soil Conservation Service

Fieldwork by Rafael A. Boccheciamp, William Francia Rivera, Julio E. Trigo,
G. Torres Ricci, Jose E. Brunet, and Luis H. Rivera,
Soil Conservation Service

United States Department of Agriculture, Soil Conservation Service, in
cooperation with the University of Puerto Rico,
Agricultural Experiment Station


General nature of the area
The island of Puerto Rico is the smallest and farthest
east of the four islands Cuba, Jamaica, Hispaniola, and
Puerto Rico known as the Greater Antilles. It lies in the
Torrid Zone. The north central coast of Puerto Rico is
about 1,600 statute miles southeast of New York City,
and the western part of the island is about 450 miles from
the eastern point of Cuba. Ponce, on the south coast, is
about 525 miles due north of Caracas, Venezuela.
The island was discovered by Christopher Columbus on
his second voyage, November 19, 1493. The native inhabi-
tants of the island, the friendly Taino Indians of the
Arawak culture, lived in small villages, each ruled by a
cacique, a chief. They grew food crops such as cassava
and corn, and also tobacco and cotton. They also fished
and hunted birds for their subsistence. They were clever
at working stones, clay, and gold and adorned themselves
with ornaments of these materials. The island was first
settled in 1508 by Juan Ponce de Leon.
The San Juan Soil Survey Area is in northeast-central
Puerto Rico (see facing page). It is bounded on the north
by the Atlantic Ocean. San Juan, the capital of Puerto
Rico, is in the northern part of the survey area.
Mayaguez is 98 miles from San Juan. Ponce, the second
largest city on the island, is 75 miles from the capital. The
survey area covers an area of 447,279 acres. According to
the census of 1970, the population totaled 1,172,609, of
which 286,906 was rural and 885,703 urban. At that time
there were 8,646 farms in the survey area.
The area consists of three major physiographic areas:
the nearly level to sloping coastal plain, which is 10 per-
cent of the area; the haystacks or limestone hills with
their remarkable karst topography, which is about 4 per-
cent; and the extensive igneous upland, which is 86 per-
cent.
There are five soil conservation districts in the San
Juan Soil Survey Area, namely: the Cibuco SCD, 80,101
acres, the municipalities of Corozal, Comerio, Naranjito,
and Toa Alta; the San Juan SCD, 122,372 acres, the mu-
nicipalities of Bayamon, Dorado, Toa Baja, Catano,


Guaynabo, Rio Piedras, and Trujillo Alto; the Torito SCD,
74,533 acres, the municipalities of Cayey, Cidra, and
Aguas Buenas; the Turabo SCD, 88,643 acres, the mu-
nicipalities of Caguas, Gurabo, and San Lorenzo; and the
Torrecillas SCD, 81,630 acres, the municipalities of Bar-
ranquitas, Aibonito, and Orocovis.
Farming is the principal enterprise of the area. Nu-
merous industries, among which is the Consolidated Cigar
Company, the largest cigar factory in the world, con-
tribute to the welfare and economy of the island.
Improved pasture such as pangolagrass, stargrass, and
Merker grass cover about 210,750 acres, or 47 percent of
the area, according to the census of Agriculture of 1969.
Most of the pastureland is used for raising beef and dairy
cattle.
The principal cash and food crops of the area are plan-
tains, taniers, yams, and tobacco. The total acreage is
89,353, or 20 percent of the area.
Woodland covers 72,239 acres, or 16 percent of the sur-
vey area.

Climate

In the San Juan Area of Puerto Rico the days are hot,
except in January and February. The nights are warm all
year. Winds from the Atlantic Ocean lower the afternoon
temperatures on most days. Temperatures in the moun-
tains of the interior are appreciably lower than elsewhere,
but freezing temperatures are unknown anywhere in the
area. Rainfall is abundant throughout the year in most of
the area. The least falls in February and March. Except
for the semiarid southernmost part, rainfall is heaviest in
the mountains.
Tables 1 and 2 list data on temperature and precipita-
tion for the survey area, as recorded at San Juan Airport
for the period 1955 to 1974 and at Barranquitas, which is
2200 feet higher than San Juan, for the period 1963 to
1974.
In winter the average temperature at San Juan is 77
degrees F, and the average daily minimum temperature is
70.-The lowest temperature on record, which occurred at







SOIL SURVEY


San Juan on March 3, 1957, is 60 degrees. In summer the
average temperature is 82 degrees, and the average daily
maximum temperature is 88. The highest recorded tem-
perature, which occurred on June 21, 1972, is 96 degrees.
In winter the average temperature at Barranquitas is
69 degrees, and the average daily minimum temperature
is 61. In summer the average temperature is 74 degrees,
and the average daily maximum temperature is 82. The
highest recorded temperature, which occurred on October
2, 1969, is 96 degrees.
Growing degree days, shown in tables 1 and 2, are
equivalent to "heat units." During the month, growing
degree days accumulate by the amount that the average
temperature each day exceeds a base temperature (60
degrees F).
Of the total annual precipitation at San Juan, 31 inches,
or 56 percent, usually falls in April through September,
which includes the growing season for most crops. In 2
years out of 10, the rainfall in April through September is
less than 23 inches. The heaviest 1-day rainfall during the
period of record was 5.01 inches at San Juan on August 6,
1955.
Of the total annual precipitation at Barranquitas, 28
inches, or 49 percent, usually falls in April through Sep-
tember. In 2 years out of 10, the rainfall during this
period is less than 19 inches. The heaviest 1-day rainfall
during the period of record at Barranquitas was 8.70
inches on October 9, 1970.
From June through November, an occasional tropical
depression skirts or crosses the area and produces heavy
rainfall that causes severe flooding. Thunderstorms
number about 40 each year, 17 of which occur in summer.
Every 10 to 20 years a hurricane causes wind damage and
flooding.
The average relative humidity in midafternoon is about
65 percent. Humidity is higher at night, and the average
at dawn is about 80 percent. The percentage of possible
sunshine is 60. The prevailing wind is from the northeast.
Average windspeed is highest, 10 miles per hour, in
March.
Climatic data in this section were specially prepared for
the Soil Conservation Service by the National Climatic
Center, Asheville, North Carolina.


How this survey was made

Soil scientists made this survey to learn what kinds of
soil are in the survey area, where they are, and how they
can be used. The soil scientists went into the area know-
ing they likely would locate many soils they already knew
something about and perhaps identify some they had
never seen before. They observed the steepness, length,
and shape of slopes; the size of streams and the general
pattern of drainage; the kinds of native plants or crops;
the kinds of rock; and many facts about the soils. They
dug many holes to expose soil profiles. A profile is the
sequence of natural layers, or horizons, in a soil; it ex-


tends from the surface down into the parent material,
which has been changed very little by leaching or by the
action of plant roots.
The soil scientists recorded the characteristics of the
profiles they studied, and they compared those profiles
with others in areas nearby and in places more distant.
Thus, through correlation, they classified and named the
soils according to nationwide, uniform procedures.
After a guide for classifying and naming the soils was
worked out, the soil scientists drew the boundaries of the
individual soils on aerial photographs. These photographs
show woodlands, buildings, field borders, roads, and other
details that help in drawing boundaries accurately. The
soil map at the back of this publication was prepared
from aerial photographs.
The areas shown on a soil map are called soil map units.
Some map units are made up of one kind of soil, others
are made up of two or more kinds of soil, and a few have
little or no soil material at all. Map units are discussed in
the sections "General soil map for broad land use
planning" and "Soil maps for detailed planning."
While a soil survey is in progress, samples of soils are
taken as needed for laboratory measurements and for en-
gineering tests. The soils are field tested, and interpreta-
tions of their behavior are modified as necessary during
the course of the survey. New interpretations are added
to meet local needs, mainly through field observations of
different kinds of soil in different uses under different
levels of management. Also, data are assembled from
other sources, such as test results, records, field ex-
perience, and information available from state and local
specialists. For example, data on crop yields under
defined practices are assembled from farm records and
from field or plot experiments on the same kinds of soil.
But only part of a soil survey is done when the soils
have been named, described, interpreted, and delineated
on aerial photographs and when the laboratory data and
other data have been assembled. The mass of detailed in-
formation then needs to be organized so that it is readily
available to different groups of users, among them far-
mers, managers of rangeland and woodland, engineers,
planners, developers and builders, homebuyers, and those
seeking recreation.


General soil map for broad land use
planning
The general soil map at the back of this publication
shows, in color, map units that have a distinct pattern of
soils and of relief and drainage. Each map unit is a unique
natural landscape. Typically, a map unit consists of one or
more major soils and some minor soils. It is named for
the major soils. The soils making up one unit can occur in
other units but in a different pattern.
The general soil map provides a broad perspective of
the soils and landscapes in the survey area. It provides a
basis for comparing the potential of large areas for







SOIL SURVEY


San Juan on March 3, 1957, is 60 degrees. In summer the
average temperature is 82 degrees, and the average daily
maximum temperature is 88. The highest recorded tem-
perature, which occurred on June 21, 1972, is 96 degrees.
In winter the average temperature at Barranquitas is
69 degrees, and the average daily minimum temperature
is 61. In summer the average temperature is 74 degrees,
and the average daily maximum temperature is 82. The
highest recorded temperature, which occurred on October
2, 1969, is 96 degrees.
Growing degree days, shown in tables 1 and 2, are
equivalent to "heat units." During the month, growing
degree days accumulate by the amount that the average
temperature each day exceeds a base temperature (60
degrees F).
Of the total annual precipitation at San Juan, 31 inches,
or 56 percent, usually falls in April through September,
which includes the growing season for most crops. In 2
years out of 10, the rainfall in April through September is
less than 23 inches. The heaviest 1-day rainfall during the
period of record was 5.01 inches at San Juan on August 6,
1955.
Of the total annual precipitation at Barranquitas, 28
inches, or 49 percent, usually falls in April through Sep-
tember. In 2 years out of 10, the rainfall during this
period is less than 19 inches. The heaviest 1-day rainfall
during the period of record at Barranquitas was 8.70
inches on October 9, 1970.
From June through November, an occasional tropical
depression skirts or crosses the area and produces heavy
rainfall that causes severe flooding. Thunderstorms
number about 40 each year, 17 of which occur in summer.
Every 10 to 20 years a hurricane causes wind damage and
flooding.
The average relative humidity in midafternoon is about
65 percent. Humidity is higher at night, and the average
at dawn is about 80 percent. The percentage of possible
sunshine is 60. The prevailing wind is from the northeast.
Average windspeed is highest, 10 miles per hour, in
March.
Climatic data in this section were specially prepared for
the Soil Conservation Service by the National Climatic
Center, Asheville, North Carolina.


How this survey was made

Soil scientists made this survey to learn what kinds of
soil are in the survey area, where they are, and how they
can be used. The soil scientists went into the area know-
ing they likely would locate many soils they already knew
something about and perhaps identify some they had
never seen before. They observed the steepness, length,
and shape of slopes; the size of streams and the general
pattern of drainage; the kinds of native plants or crops;
the kinds of rock; and many facts about the soils. They
dug many holes to expose soil profiles. A profile is the
sequence of natural layers, or horizons, in a soil; it ex-


tends from the surface down into the parent material,
which has been changed very little by leaching or by the
action of plant roots.
The soil scientists recorded the characteristics of the
profiles they studied, and they compared those profiles
with others in areas nearby and in places more distant.
Thus, through correlation, they classified and named the
soils according to nationwide, uniform procedures.
After a guide for classifying and naming the soils was
worked out, the soil scientists drew the boundaries of the
individual soils on aerial photographs. These photographs
show woodlands, buildings, field borders, roads, and other
details that help in drawing boundaries accurately. The
soil map at the back of this publication was prepared
from aerial photographs.
The areas shown on a soil map are called soil map units.
Some map units are made up of one kind of soil, others
are made up of two or more kinds of soil, and a few have
little or no soil material at all. Map units are discussed in
the sections "General soil map for broad land use
planning" and "Soil maps for detailed planning."
While a soil survey is in progress, samples of soils are
taken as needed for laboratory measurements and for en-
gineering tests. The soils are field tested, and interpreta-
tions of their behavior are modified as necessary during
the course of the survey. New interpretations are added
to meet local needs, mainly through field observations of
different kinds of soil in different uses under different
levels of management. Also, data are assembled from
other sources, such as test results, records, field ex-
perience, and information available from state and local
specialists. For example, data on crop yields under
defined practices are assembled from farm records and
from field or plot experiments on the same kinds of soil.
But only part of a soil survey is done when the soils
have been named, described, interpreted, and delineated
on aerial photographs and when the laboratory data and
other data have been assembled. The mass of detailed in-
formation then needs to be organized so that it is readily
available to different groups of users, among them far-
mers, managers of rangeland and woodland, engineers,
planners, developers and builders, homebuyers, and those
seeking recreation.


General soil map for broad land use
planning
The general soil map at the back of this publication
shows, in color, map units that have a distinct pattern of
soils and of relief and drainage. Each map unit is a unique
natural landscape. Typically, a map unit consists of one or
more major soils and some minor soils. It is named for
the major soils. The soils making up one unit can occur in
other units but in a different pattern.
The general soil map provides a broad perspective of
the soils and landscapes in the survey area. It provides a
basis for comparing the potential of large areas for






SAN JUAN AREA, PUERTO RICO


general kinds of land use. Areas that are, for the most
part, suited to certain kinds of farming or to other land
uses can be identified on the map. Likewise, areas of soils
having properties that are distinctly unfavorable for cer-
tain land uses can be located.
Because of its small scale, the map does not show the
kind of soil at a specific site. Thus, it is not suitable for
planning the management of a farm or field or for select-
ing a site for a road or building or other structure. The
kinds of soil in any one map unit differ from place to
place in slope, depth, stoniness, drainage, or other charac-
teristics that affect their management.
The soils in the survey area vary widely in their poten-
tial for major land uses. Table 3 shows the extent of the
map units shown on the general soil map and gives
general ratings of the potential of each, in relation to the
other map units, for major land uses. Soil properties that
pose limitations to the use are indicated. The ratings of
soil potential are based on the assumption that practices
in common use in the survey area are being used to over-
come soil limitations. These ratings reflect the ease of
overcoming the soil limitations and the probability of soil
problems persisting after such practices are used.
Each map unit is rated for cultivated farm crops, spe-
cialty crops, woodland, urban uses, and recreation areas.
Cultivated farm crops are those grown extensively by
farmers in the survey area. Specialty crops include
vegetables, fruits, and nursery crops grown on limited
acreage and generally requiring intensive management.
Woodland refers to land that is producing either trees na-
tive to the area or introduced species. Urban uses include
residential, commercial, and industrial developments. In-
tensive recreation areas include campsites, picnic areas,
ballfields, and other areas that are subject to heavy foot
traffic. Extensive recreation areas include those used for
nature study and as wilderness.

Map unit descriptions

Soils formed in residuum from basic volcanic rocks
These map units are in the central and southern parts
of the soil survey area. The soils formed mainly in clayey
material weathered from basic volcanic rocks. They are
mostly steep to very steep. A few are gently sloping to
sloping. V-shaped drainageways dissect the entire area.
Many of the soils in the humid area are planted to clean
cultivated crops regardless of the steepness of slope and
hazard of erosion. The Descalabrado unit, in the southern
part of the survey area, is mostly brushy pasture. The
semiarid climate, steepness of slope, and shallow depth to
bedrock make it unsuited to cultivated crops.

1. Maricao-Los Guineos
Deep, steep to very steep, well drained and moderately
well drained soils of the humid mountainous areas


This unit is in the southeastern part of the survey area.
The soils formed in residuum weathered from basic vol-
canic rocks. They are steep to very steep. They are used
for food crops, pasture, and forest. They receive moisture
throughout the year and are not deficient in moisture
needed for the common crops.
This unit occupies 10 percent of the total acreage. The
landscape is mountainous and is strongly dissected by in-
termittent streams. Steep to very steep side slopes and
ridges are common.
The Maricao soils are deep to hard rock, well drained,
and clayey. They are on strongly dissected uplands where
slope gradients are 20 to 60 percent. They occupy about
55 percent of the unit.
The Los Guineos soils are deep to hard rock, moderate-
ly well drained, and clayey. They are on side slopes hav-
ing gradients of 20 to 60 percent. They occupy about 40
percent of the unit.
The remaining 5 percent of the unit is made up of the
deep, well drained, clayey Humatas soils.
This unit in general has severe limitations for farming
because of the slope and the erosion hazard. Complex con-
servation practices and good management are needed in
order to produce crops. These soils are best suited to
grasses and trees. Steep slopes and the erosion hazard
make fieldwork costly and difficult.

2. Humatas-Naranjito-Consumo
Deep to moderately deep, moderately steep to very steep,
well drained soils of the humid mountainous areas
This unit, the second largest, makes up 29 percent of
the total acreage. It is in the mountainous section of the
survey area. The landscape is one of gently sloping foot
slopes to very steep side slopes and ridges that are dis-
sected by intermittent streams. These soils formed in the
residuum of weathered basic volcanic rocks and siltstone.
They are used for food crops and pasture. They receive
adequate moisture throughout the year for the crops com-
monly grown.
The Humatas soils are deep, well drained, and clayey.
They are on mountainsides where slope gradients are 20
to 60 percent. They make up about 36 percent of the unit.
The Naranjito soils are moderately deep, 20 to 40
inches to hard consolidated volcanic rocks, and are well
drained and clayey. They are on strongly dissected
uplands where slope gradients are 12 to 60 percent. They
make up about 29 percent of the unit.
The Consumo soils are deep but have very highly
weathered rock at a depth of 14 to 24 inches. They are
well drained, clayey soils on the side slopes of naturally
dissected uplands where slope gradients are 20 to 60 per-
cent. They occupy about 17 percent of the unit.
The remaining 18 percent consists of the deep, well
drained, clayey Daguey, Aceitunas, and Rio Piedras soils
and the somewhat poorly drained Lares soils.
This unit in general has severe limitations for cul-
tivated crops because of the slope and the erosion hazard.






SAN JUAN AREA, PUERTO RICO


general kinds of land use. Areas that are, for the most
part, suited to certain kinds of farming or to other land
uses can be identified on the map. Likewise, areas of soils
having properties that are distinctly unfavorable for cer-
tain land uses can be located.
Because of its small scale, the map does not show the
kind of soil at a specific site. Thus, it is not suitable for
planning the management of a farm or field or for select-
ing a site for a road or building or other structure. The
kinds of soil in any one map unit differ from place to
place in slope, depth, stoniness, drainage, or other charac-
teristics that affect their management.
The soils in the survey area vary widely in their poten-
tial for major land uses. Table 3 shows the extent of the
map units shown on the general soil map and gives
general ratings of the potential of each, in relation to the
other map units, for major land uses. Soil properties that
pose limitations to the use are indicated. The ratings of
soil potential are based on the assumption that practices
in common use in the survey area are being used to over-
come soil limitations. These ratings reflect the ease of
overcoming the soil limitations and the probability of soil
problems persisting after such practices are used.
Each map unit is rated for cultivated farm crops, spe-
cialty crops, woodland, urban uses, and recreation areas.
Cultivated farm crops are those grown extensively by
farmers in the survey area. Specialty crops include
vegetables, fruits, and nursery crops grown on limited
acreage and generally requiring intensive management.
Woodland refers to land that is producing either trees na-
tive to the area or introduced species. Urban uses include
residential, commercial, and industrial developments. In-
tensive recreation areas include campsites, picnic areas,
ballfields, and other areas that are subject to heavy foot
traffic. Extensive recreation areas include those used for
nature study and as wilderness.

Map unit descriptions

Soils formed in residuum from basic volcanic rocks
These map units are in the central and southern parts
of the soil survey area. The soils formed mainly in clayey
material weathered from basic volcanic rocks. They are
mostly steep to very steep. A few are gently sloping to
sloping. V-shaped drainageways dissect the entire area.
Many of the soils in the humid area are planted to clean
cultivated crops regardless of the steepness of slope and
hazard of erosion. The Descalabrado unit, in the southern
part of the survey area, is mostly brushy pasture. The
semiarid climate, steepness of slope, and shallow depth to
bedrock make it unsuited to cultivated crops.

1. Maricao-Los Guineos
Deep, steep to very steep, well drained and moderately
well drained soils of the humid mountainous areas


This unit is in the southeastern part of the survey area.
The soils formed in residuum weathered from basic vol-
canic rocks. They are steep to very steep. They are used
for food crops, pasture, and forest. They receive moisture
throughout the year and are not deficient in moisture
needed for the common crops.
This unit occupies 10 percent of the total acreage. The
landscape is mountainous and is strongly dissected by in-
termittent streams. Steep to very steep side slopes and
ridges are common.
The Maricao soils are deep to hard rock, well drained,
and clayey. They are on strongly dissected uplands where
slope gradients are 20 to 60 percent. They occupy about
55 percent of the unit.
The Los Guineos soils are deep to hard rock, moderate-
ly well drained, and clayey. They are on side slopes hav-
ing gradients of 20 to 60 percent. They occupy about 40
percent of the unit.
The remaining 5 percent of the unit is made up of the
deep, well drained, clayey Humatas soils.
This unit in general has severe limitations for farming
because of the slope and the erosion hazard. Complex con-
servation practices and good management are needed in
order to produce crops. These soils are best suited to
grasses and trees. Steep slopes and the erosion hazard
make fieldwork costly and difficult.

2. Humatas-Naranjito-Consumo
Deep to moderately deep, moderately steep to very steep,
well drained soils of the humid mountainous areas
This unit, the second largest, makes up 29 percent of
the total acreage. It is in the mountainous section of the
survey area. The landscape is one of gently sloping foot
slopes to very steep side slopes and ridges that are dis-
sected by intermittent streams. These soils formed in the
residuum of weathered basic volcanic rocks and siltstone.
They are used for food crops and pasture. They receive
adequate moisture throughout the year for the crops com-
monly grown.
The Humatas soils are deep, well drained, and clayey.
They are on mountainsides where slope gradients are 20
to 60 percent. They make up about 36 percent of the unit.
The Naranjito soils are moderately deep, 20 to 40
inches to hard consolidated volcanic rocks, and are well
drained and clayey. They are on strongly dissected
uplands where slope gradients are 12 to 60 percent. They
make up about 29 percent of the unit.
The Consumo soils are deep but have very highly
weathered rock at a depth of 14 to 24 inches. They are
well drained, clayey soils on the side slopes of naturally
dissected uplands where slope gradients are 20 to 60 per-
cent. They occupy about 17 percent of the unit.
The remaining 18 percent consists of the deep, well
drained, clayey Daguey, Aceitunas, and Rio Piedras soils
and the somewhat poorly drained Lares soils.
This unit in general has severe limitations for cul-
tivated crops because of the slope and the erosion hazard.






SAN JUAN AREA, PUERTO RICO


general kinds of land use. Areas that are, for the most
part, suited to certain kinds of farming or to other land
uses can be identified on the map. Likewise, areas of soils
having properties that are distinctly unfavorable for cer-
tain land uses can be located.
Because of its small scale, the map does not show the
kind of soil at a specific site. Thus, it is not suitable for
planning the management of a farm or field or for select-
ing a site for a road or building or other structure. The
kinds of soil in any one map unit differ from place to
place in slope, depth, stoniness, drainage, or other charac-
teristics that affect their management.
The soils in the survey area vary widely in their poten-
tial for major land uses. Table 3 shows the extent of the
map units shown on the general soil map and gives
general ratings of the potential of each, in relation to the
other map units, for major land uses. Soil properties that
pose limitations to the use are indicated. The ratings of
soil potential are based on the assumption that practices
in common use in the survey area are being used to over-
come soil limitations. These ratings reflect the ease of
overcoming the soil limitations and the probability of soil
problems persisting after such practices are used.
Each map unit is rated for cultivated farm crops, spe-
cialty crops, woodland, urban uses, and recreation areas.
Cultivated farm crops are those grown extensively by
farmers in the survey area. Specialty crops include
vegetables, fruits, and nursery crops grown on limited
acreage and generally requiring intensive management.
Woodland refers to land that is producing either trees na-
tive to the area or introduced species. Urban uses include
residential, commercial, and industrial developments. In-
tensive recreation areas include campsites, picnic areas,
ballfields, and other areas that are subject to heavy foot
traffic. Extensive recreation areas include those used for
nature study and as wilderness.

Map unit descriptions

Soils formed in residuum from basic volcanic rocks
These map units are in the central and southern parts
of the soil survey area. The soils formed mainly in clayey
material weathered from basic volcanic rocks. They are
mostly steep to very steep. A few are gently sloping to
sloping. V-shaped drainageways dissect the entire area.
Many of the soils in the humid area are planted to clean
cultivated crops regardless of the steepness of slope and
hazard of erosion. The Descalabrado unit, in the southern
part of the survey area, is mostly brushy pasture. The
semiarid climate, steepness of slope, and shallow depth to
bedrock make it unsuited to cultivated crops.

1. Maricao-Los Guineos
Deep, steep to very steep, well drained and moderately
well drained soils of the humid mountainous areas


This unit is in the southeastern part of the survey area.
The soils formed in residuum weathered from basic vol-
canic rocks. They are steep to very steep. They are used
for food crops, pasture, and forest. They receive moisture
throughout the year and are not deficient in moisture
needed for the common crops.
This unit occupies 10 percent of the total acreage. The
landscape is mountainous and is strongly dissected by in-
termittent streams. Steep to very steep side slopes and
ridges are common.
The Maricao soils are deep to hard rock, well drained,
and clayey. They are on strongly dissected uplands where
slope gradients are 20 to 60 percent. They occupy about
55 percent of the unit.
The Los Guineos soils are deep to hard rock, moderate-
ly well drained, and clayey. They are on side slopes hav-
ing gradients of 20 to 60 percent. They occupy about 40
percent of the unit.
The remaining 5 percent of the unit is made up of the
deep, well drained, clayey Humatas soils.
This unit in general has severe limitations for farming
because of the slope and the erosion hazard. Complex con-
servation practices and good management are needed in
order to produce crops. These soils are best suited to
grasses and trees. Steep slopes and the erosion hazard
make fieldwork costly and difficult.

2. Humatas-Naranjito-Consumo
Deep to moderately deep, moderately steep to very steep,
well drained soils of the humid mountainous areas
This unit, the second largest, makes up 29 percent of
the total acreage. It is in the mountainous section of the
survey area. The landscape is one of gently sloping foot
slopes to very steep side slopes and ridges that are dis-
sected by intermittent streams. These soils formed in the
residuum of weathered basic volcanic rocks and siltstone.
They are used for food crops and pasture. They receive
adequate moisture throughout the year for the crops com-
monly grown.
The Humatas soils are deep, well drained, and clayey.
They are on mountainsides where slope gradients are 20
to 60 percent. They make up about 36 percent of the unit.
The Naranjito soils are moderately deep, 20 to 40
inches to hard consolidated volcanic rocks, and are well
drained and clayey. They are on strongly dissected
uplands where slope gradients are 12 to 60 percent. They
make up about 29 percent of the unit.
The Consumo soils are deep but have very highly
weathered rock at a depth of 14 to 24 inches. They are
well drained, clayey soils on the side slopes of naturally
dissected uplands where slope gradients are 20 to 60 per-
cent. They occupy about 17 percent of the unit.
The remaining 18 percent consists of the deep, well
drained, clayey Daguey, Aceitunas, and Rio Piedras soils
and the somewhat poorly drained Lares soils.
This unit in general has severe limitations for cul-
tivated crops because of the slope and the erosion hazard.






SAN JUAN AREA, PUERTO RICO


general kinds of land use. Areas that are, for the most
part, suited to certain kinds of farming or to other land
uses can be identified on the map. Likewise, areas of soils
having properties that are distinctly unfavorable for cer-
tain land uses can be located.
Because of its small scale, the map does not show the
kind of soil at a specific site. Thus, it is not suitable for
planning the management of a farm or field or for select-
ing a site for a road or building or other structure. The
kinds of soil in any one map unit differ from place to
place in slope, depth, stoniness, drainage, or other charac-
teristics that affect their management.
The soils in the survey area vary widely in their poten-
tial for major land uses. Table 3 shows the extent of the
map units shown on the general soil map and gives
general ratings of the potential of each, in relation to the
other map units, for major land uses. Soil properties that
pose limitations to the use are indicated. The ratings of
soil potential are based on the assumption that practices
in common use in the survey area are being used to over-
come soil limitations. These ratings reflect the ease of
overcoming the soil limitations and the probability of soil
problems persisting after such practices are used.
Each map unit is rated for cultivated farm crops, spe-
cialty crops, woodland, urban uses, and recreation areas.
Cultivated farm crops are those grown extensively by
farmers in the survey area. Specialty crops include
vegetables, fruits, and nursery crops grown on limited
acreage and generally requiring intensive management.
Woodland refers to land that is producing either trees na-
tive to the area or introduced species. Urban uses include
residential, commercial, and industrial developments. In-
tensive recreation areas include campsites, picnic areas,
ballfields, and other areas that are subject to heavy foot
traffic. Extensive recreation areas include those used for
nature study and as wilderness.

Map unit descriptions

Soils formed in residuum from basic volcanic rocks
These map units are in the central and southern parts
of the soil survey area. The soils formed mainly in clayey
material weathered from basic volcanic rocks. They are
mostly steep to very steep. A few are gently sloping to
sloping. V-shaped drainageways dissect the entire area.
Many of the soils in the humid area are planted to clean
cultivated crops regardless of the steepness of slope and
hazard of erosion. The Descalabrado unit, in the southern
part of the survey area, is mostly brushy pasture. The
semiarid climate, steepness of slope, and shallow depth to
bedrock make it unsuited to cultivated crops.

1. Maricao-Los Guineos
Deep, steep to very steep, well drained and moderately
well drained soils of the humid mountainous areas


This unit is in the southeastern part of the survey area.
The soils formed in residuum weathered from basic vol-
canic rocks. They are steep to very steep. They are used
for food crops, pasture, and forest. They receive moisture
throughout the year and are not deficient in moisture
needed for the common crops.
This unit occupies 10 percent of the total acreage. The
landscape is mountainous and is strongly dissected by in-
termittent streams. Steep to very steep side slopes and
ridges are common.
The Maricao soils are deep to hard rock, well drained,
and clayey. They are on strongly dissected uplands where
slope gradients are 20 to 60 percent. They occupy about
55 percent of the unit.
The Los Guineos soils are deep to hard rock, moderate-
ly well drained, and clayey. They are on side slopes hav-
ing gradients of 20 to 60 percent. They occupy about 40
percent of the unit.
The remaining 5 percent of the unit is made up of the
deep, well drained, clayey Humatas soils.
This unit in general has severe limitations for farming
because of the slope and the erosion hazard. Complex con-
servation practices and good management are needed in
order to produce crops. These soils are best suited to
grasses and trees. Steep slopes and the erosion hazard
make fieldwork costly and difficult.

2. Humatas-Naranjito-Consumo
Deep to moderately deep, moderately steep to very steep,
well drained soils of the humid mountainous areas
This unit, the second largest, makes up 29 percent of
the total acreage. It is in the mountainous section of the
survey area. The landscape is one of gently sloping foot
slopes to very steep side slopes and ridges that are dis-
sected by intermittent streams. These soils formed in the
residuum of weathered basic volcanic rocks and siltstone.
They are used for food crops and pasture. They receive
adequate moisture throughout the year for the crops com-
monly grown.
The Humatas soils are deep, well drained, and clayey.
They are on mountainsides where slope gradients are 20
to 60 percent. They make up about 36 percent of the unit.
The Naranjito soils are moderately deep, 20 to 40
inches to hard consolidated volcanic rocks, and are well
drained and clayey. They are on strongly dissected
uplands where slope gradients are 12 to 60 percent. They
make up about 29 percent of the unit.
The Consumo soils are deep but have very highly
weathered rock at a depth of 14 to 24 inches. They are
well drained, clayey soils on the side slopes of naturally
dissected uplands where slope gradients are 20 to 60 per-
cent. They occupy about 17 percent of the unit.
The remaining 18 percent consists of the deep, well
drained, clayey Daguey, Aceitunas, and Rio Piedras soils
and the somewhat poorly drained Lares soils.
This unit in general has severe limitations for cul-
tivated crops because of the slope and the erosion hazard.







SOIL SURVEY


The less steep slopes are suitable for cultivation if com-
plex soil conservation practices are applied and the soils
are well managed. Liming and fertilizing are necessary
for better crop yields. The use of machinery is not feasi-
ble on most of this unit. The slope is a severe limitation
for buildings or other developments.

3. Mucara-Caguabo
Moderately deep to shallow, moderately steep to very
steep, well drained soils of the humid mountainous areas
This unit, the largest, makes up about 39 percent of the
total survey area. The landscape is mountainous and is
highly dissected by intermittent streams. Narrow ridges
are common. This unit is in the humid mountainous region
of the survey area extending from the vicinity of
Orocovis to San Lorenzo.
The Mucara soils are moderately deep, 20 to 40 inches
to semiconsolidated rock, and are well drained and clayey.
They are on side slopes of strongly dissected uplands
where slope gradients are 12 to 60 percent. They make up
about 58 percent of the unit.
The Caguabo soils are shallow to hard rock, well
drained, and loamy. They are on side slopes and ridgetops
where slope gradients are 20 to 60 percent. They make up
about 37 percent of the unit. In some areas the surface of
these soils is covered with stones.
The remaining 5 percent consists of the well drained,
loamy Morado and Sabana soils and the moderately well
drained, clayey Juncos soils. The Morado and Sabana soils
occupy similar positions on the landscape as the Mucara
and Caguabo soils. The Juncos soils, which are more
gently sloping, occupy the side slopes and foot slopes of
strongly dissected uplands.
This unit in general is not suitable for cultivation
because of the slope, erosion hazard, rapid runoff, and
depth to rock. It is suitable for pasture and woodland. A
large acreage is in brush and brushy native pasture. Some
areas have been cleared and planted to pangolagrass.
Small patches are in food crops. Steep slopes, the erosion
hazard, and the depth to rock are permanent limitations
that preclude the use of these soils for clean cultivation.
Fieldwork is difficult and costly. The soils have severe
limitations for nonfarm uses such as dwellings, roads,
recreational facilities, and other intensive developments.

4. Descalabrado
Shallow, very steep, well drained soils of the semiarid
mountainous areas
This unit is in the southern part of the survey area.
The soils formed in the residuum of weathered basic vol-
canic rocks. They do not receive enough rainfall
throughout the year and are deficient in moisture needed
for growing common cultivated crops. The topography is
rugged and very steep. This unit makes up 1 percent of
the total survey area.


The Descalabrado soils are shallow to volcanic rock and
well drained. They are on side slopes where slope
gradients are 40 to 60 percent. They make up 91 percent
of the unit. The remaining 9 percent consists of boulders
and the shallow, well drained, acid Guayama soils.
Because of the low rainfall of the area, most of the soils
are in native guineagrass and brush. Clean tilled crops
are not suited because of the slopes, depth to rock, and
moisture deficiency. Most of the plant cover dies during
long periods of drought.

Soils formed in residuum from intrusive igneous rocks
This unit is in the southeastern part of the survey area
near the town of San Lorenzo. The soils formed mainly in
the residuum of granitic rocks. Most are steep and very
steep. The landscape is mountainous, with V-shaped
drainageways dissecting the entire area and with narrow,
knife-like ridges, gullies, and slips. Some of the soils are
planted to clean cultivated food crops, but many are in
native and improved pasture. Most soils in this unit have
low potential for crops because of the steep slopes and
shallow depth to the granitic rock.

5. Pandura-Lirios
Shallow to deep, moderately steep to very steep, well
drained soils of the humid mountainous areas
This unit, one of the smaller, makes up 7 percent of the
total acreage of the soil survey area. It is in the vicinity
of San Lorenzo. The soils formed in the residuum of
granitic rock that is part of the San Lorenzo Batholith.
The landscape is mountainous and is highly dissected by
numerous intermittent streams. Narrow ridges, gullies,
and slip areas are common.
The Pandura soils are shallow to weathered granitic
rocks, well drained, loamy, moderately steep to steep.
They are on side slopes of the granitic uplands where
slope gradients are 12 to 60 percent. They make up about
.62 percent of the unit.
The Lirios soils are deep, but highly weathered granitic
rock is at a depth of 20 to 34 inches. These are well
drained, steep to very steep soils with a clayey subsoil.
They are on side slopes and narrow ridgetops where slope
gradients are 20 to 60 percent. They make up 26 percent
of the unit.
The remaining 12 percent of the unit is made up of the
deep, well drained, clayey Limones and Jagueyes soils and
the somewhat poorly drained, clayey Cayagua soils. The
Limones and Jagueyes soils are on side slopes and narrow
ridgetops where slope gradients are 20 to 60 percent.
This unit in general has severe limitations for farming
because of the slope, erosion hazard, and low fertility of
the soils. It has been intensively cultivated for food crops.
Some areas are in improved pasture. Others are in brush
and brushy pasture.
Steep slopes and the erosion hazard are permanent
limitations that preclude the use of these soils for clean
cultivated crops. The slope is a severe limitation for non-







SOIL SURVEY


The less steep slopes are suitable for cultivation if com-
plex soil conservation practices are applied and the soils
are well managed. Liming and fertilizing are necessary
for better crop yields. The use of machinery is not feasi-
ble on most of this unit. The slope is a severe limitation
for buildings or other developments.

3. Mucara-Caguabo
Moderately deep to shallow, moderately steep to very
steep, well drained soils of the humid mountainous areas
This unit, the largest, makes up about 39 percent of the
total survey area. The landscape is mountainous and is
highly dissected by intermittent streams. Narrow ridges
are common. This unit is in the humid mountainous region
of the survey area extending from the vicinity of
Orocovis to San Lorenzo.
The Mucara soils are moderately deep, 20 to 40 inches
to semiconsolidated rock, and are well drained and clayey.
They are on side slopes of strongly dissected uplands
where slope gradients are 12 to 60 percent. They make up
about 58 percent of the unit.
The Caguabo soils are shallow to hard rock, well
drained, and loamy. They are on side slopes and ridgetops
where slope gradients are 20 to 60 percent. They make up
about 37 percent of the unit. In some areas the surface of
these soils is covered with stones.
The remaining 5 percent consists of the well drained,
loamy Morado and Sabana soils and the moderately well
drained, clayey Juncos soils. The Morado and Sabana soils
occupy similar positions on the landscape as the Mucara
and Caguabo soils. The Juncos soils, which are more
gently sloping, occupy the side slopes and foot slopes of
strongly dissected uplands.
This unit in general is not suitable for cultivation
because of the slope, erosion hazard, rapid runoff, and
depth to rock. It is suitable for pasture and woodland. A
large acreage is in brush and brushy native pasture. Some
areas have been cleared and planted to pangolagrass.
Small patches are in food crops. Steep slopes, the erosion
hazard, and the depth to rock are permanent limitations
that preclude the use of these soils for clean cultivation.
Fieldwork is difficult and costly. The soils have severe
limitations for nonfarm uses such as dwellings, roads,
recreational facilities, and other intensive developments.

4. Descalabrado
Shallow, very steep, well drained soils of the semiarid
mountainous areas
This unit is in the southern part of the survey area.
The soils formed in the residuum of weathered basic vol-
canic rocks. They do not receive enough rainfall
throughout the year and are deficient in moisture needed
for growing common cultivated crops. The topography is
rugged and very steep. This unit makes up 1 percent of
the total survey area.


The Descalabrado soils are shallow to volcanic rock and
well drained. They are on side slopes where slope
gradients are 40 to 60 percent. They make up 91 percent
of the unit. The remaining 9 percent consists of boulders
and the shallow, well drained, acid Guayama soils.
Because of the low rainfall of the area, most of the soils
are in native guineagrass and brush. Clean tilled crops
are not suited because of the slopes, depth to rock, and
moisture deficiency. Most of the plant cover dies during
long periods of drought.

Soils formed in residuum from intrusive igneous rocks
This unit is in the southeastern part of the survey area
near the town of San Lorenzo. The soils formed mainly in
the residuum of granitic rocks. Most are steep and very
steep. The landscape is mountainous, with V-shaped
drainageways dissecting the entire area and with narrow,
knife-like ridges, gullies, and slips. Some of the soils are
planted to clean cultivated food crops, but many are in
native and improved pasture. Most soils in this unit have
low potential for crops because of the steep slopes and
shallow depth to the granitic rock.

5. Pandura-Lirios
Shallow to deep, moderately steep to very steep, well
drained soils of the humid mountainous areas
This unit, one of the smaller, makes up 7 percent of the
total acreage of the soil survey area. It is in the vicinity
of San Lorenzo. The soils formed in the residuum of
granitic rock that is part of the San Lorenzo Batholith.
The landscape is mountainous and is highly dissected by
numerous intermittent streams. Narrow ridges, gullies,
and slip areas are common.
The Pandura soils are shallow to weathered granitic
rocks, well drained, loamy, moderately steep to steep.
They are on side slopes of the granitic uplands where
slope gradients are 12 to 60 percent. They make up about
.62 percent of the unit.
The Lirios soils are deep, but highly weathered granitic
rock is at a depth of 20 to 34 inches. These are well
drained, steep to very steep soils with a clayey subsoil.
They are on side slopes and narrow ridgetops where slope
gradients are 20 to 60 percent. They make up 26 percent
of the unit.
The remaining 12 percent of the unit is made up of the
deep, well drained, clayey Limones and Jagueyes soils and
the somewhat poorly drained, clayey Cayagua soils. The
Limones and Jagueyes soils are on side slopes and narrow
ridgetops where slope gradients are 20 to 60 percent.
This unit in general has severe limitations for farming
because of the slope, erosion hazard, and low fertility of
the soils. It has been intensively cultivated for food crops.
Some areas are in improved pasture. Others are in brush
and brushy pasture.
Steep slopes and the erosion hazard are permanent
limitations that preclude the use of these soils for clean
cultivated crops. The slope is a severe limitation for non-







SOIL SURVEY


The less steep slopes are suitable for cultivation if com-
plex soil conservation practices are applied and the soils
are well managed. Liming and fertilizing are necessary
for better crop yields. The use of machinery is not feasi-
ble on most of this unit. The slope is a severe limitation
for buildings or other developments.

3. Mucara-Caguabo
Moderately deep to shallow, moderately steep to very
steep, well drained soils of the humid mountainous areas
This unit, the largest, makes up about 39 percent of the
total survey area. The landscape is mountainous and is
highly dissected by intermittent streams. Narrow ridges
are common. This unit is in the humid mountainous region
of the survey area extending from the vicinity of
Orocovis to San Lorenzo.
The Mucara soils are moderately deep, 20 to 40 inches
to semiconsolidated rock, and are well drained and clayey.
They are on side slopes of strongly dissected uplands
where slope gradients are 12 to 60 percent. They make up
about 58 percent of the unit.
The Caguabo soils are shallow to hard rock, well
drained, and loamy. They are on side slopes and ridgetops
where slope gradients are 20 to 60 percent. They make up
about 37 percent of the unit. In some areas the surface of
these soils is covered with stones.
The remaining 5 percent consists of the well drained,
loamy Morado and Sabana soils and the moderately well
drained, clayey Juncos soils. The Morado and Sabana soils
occupy similar positions on the landscape as the Mucara
and Caguabo soils. The Juncos soils, which are more
gently sloping, occupy the side slopes and foot slopes of
strongly dissected uplands.
This unit in general is not suitable for cultivation
because of the slope, erosion hazard, rapid runoff, and
depth to rock. It is suitable for pasture and woodland. A
large acreage is in brush and brushy native pasture. Some
areas have been cleared and planted to pangolagrass.
Small patches are in food crops. Steep slopes, the erosion
hazard, and the depth to rock are permanent limitations
that preclude the use of these soils for clean cultivation.
Fieldwork is difficult and costly. The soils have severe
limitations for nonfarm uses such as dwellings, roads,
recreational facilities, and other intensive developments.

4. Descalabrado
Shallow, very steep, well drained soils of the semiarid
mountainous areas
This unit is in the southern part of the survey area.
The soils formed in the residuum of weathered basic vol-
canic rocks. They do not receive enough rainfall
throughout the year and are deficient in moisture needed
for growing common cultivated crops. The topography is
rugged and very steep. This unit makes up 1 percent of
the total survey area.


The Descalabrado soils are shallow to volcanic rock and
well drained. They are on side slopes where slope
gradients are 40 to 60 percent. They make up 91 percent
of the unit. The remaining 9 percent consists of boulders
and the shallow, well drained, acid Guayama soils.
Because of the low rainfall of the area, most of the soils
are in native guineagrass and brush. Clean tilled crops
are not suited because of the slopes, depth to rock, and
moisture deficiency. Most of the plant cover dies during
long periods of drought.

Soils formed in residuum from intrusive igneous rocks
This unit is in the southeastern part of the survey area
near the town of San Lorenzo. The soils formed mainly in
the residuum of granitic rocks. Most are steep and very
steep. The landscape is mountainous, with V-shaped
drainageways dissecting the entire area and with narrow,
knife-like ridges, gullies, and slips. Some of the soils are
planted to clean cultivated food crops, but many are in
native and improved pasture. Most soils in this unit have
low potential for crops because of the steep slopes and
shallow depth to the granitic rock.

5. Pandura-Lirios
Shallow to deep, moderately steep to very steep, well
drained soils of the humid mountainous areas
This unit, one of the smaller, makes up 7 percent of the
total acreage of the soil survey area. It is in the vicinity
of San Lorenzo. The soils formed in the residuum of
granitic rock that is part of the San Lorenzo Batholith.
The landscape is mountainous and is highly dissected by
numerous intermittent streams. Narrow ridges, gullies,
and slip areas are common.
The Pandura soils are shallow to weathered granitic
rocks, well drained, loamy, moderately steep to steep.
They are on side slopes of the granitic uplands where
slope gradients are 12 to 60 percent. They make up about
.62 percent of the unit.
The Lirios soils are deep, but highly weathered granitic
rock is at a depth of 20 to 34 inches. These are well
drained, steep to very steep soils with a clayey subsoil.
They are on side slopes and narrow ridgetops where slope
gradients are 20 to 60 percent. They make up 26 percent
of the unit.
The remaining 12 percent of the unit is made up of the
deep, well drained, clayey Limones and Jagueyes soils and
the somewhat poorly drained, clayey Cayagua soils. The
Limones and Jagueyes soils are on side slopes and narrow
ridgetops where slope gradients are 20 to 60 percent.
This unit in general has severe limitations for farming
because of the slope, erosion hazard, and low fertility of
the soils. It has been intensively cultivated for food crops.
Some areas are in improved pasture. Others are in brush
and brushy pasture.
Steep slopes and the erosion hazard are permanent
limitations that preclude the use of these soils for clean
cultivated crops. The slope is a severe limitation for non-







SOIL SURVEY


The less steep slopes are suitable for cultivation if com-
plex soil conservation practices are applied and the soils
are well managed. Liming and fertilizing are necessary
for better crop yields. The use of machinery is not feasi-
ble on most of this unit. The slope is a severe limitation
for buildings or other developments.

3. Mucara-Caguabo
Moderately deep to shallow, moderately steep to very
steep, well drained soils of the humid mountainous areas
This unit, the largest, makes up about 39 percent of the
total survey area. The landscape is mountainous and is
highly dissected by intermittent streams. Narrow ridges
are common. This unit is in the humid mountainous region
of the survey area extending from the vicinity of
Orocovis to San Lorenzo.
The Mucara soils are moderately deep, 20 to 40 inches
to semiconsolidated rock, and are well drained and clayey.
They are on side slopes of strongly dissected uplands
where slope gradients are 12 to 60 percent. They make up
about 58 percent of the unit.
The Caguabo soils are shallow to hard rock, well
drained, and loamy. They are on side slopes and ridgetops
where slope gradients are 20 to 60 percent. They make up
about 37 percent of the unit. In some areas the surface of
these soils is covered with stones.
The remaining 5 percent consists of the well drained,
loamy Morado and Sabana soils and the moderately well
drained, clayey Juncos soils. The Morado and Sabana soils
occupy similar positions on the landscape as the Mucara
and Caguabo soils. The Juncos soils, which are more
gently sloping, occupy the side slopes and foot slopes of
strongly dissected uplands.
This unit in general is not suitable for cultivation
because of the slope, erosion hazard, rapid runoff, and
depth to rock. It is suitable for pasture and woodland. A
large acreage is in brush and brushy native pasture. Some
areas have been cleared and planted to pangolagrass.
Small patches are in food crops. Steep slopes, the erosion
hazard, and the depth to rock are permanent limitations
that preclude the use of these soils for clean cultivation.
Fieldwork is difficult and costly. The soils have severe
limitations for nonfarm uses such as dwellings, roads,
recreational facilities, and other intensive developments.

4. Descalabrado
Shallow, very steep, well drained soils of the semiarid
mountainous areas
This unit is in the southern part of the survey area.
The soils formed in the residuum of weathered basic vol-
canic rocks. They do not receive enough rainfall
throughout the year and are deficient in moisture needed
for growing common cultivated crops. The topography is
rugged and very steep. This unit makes up 1 percent of
the total survey area.


The Descalabrado soils are shallow to volcanic rock and
well drained. They are on side slopes where slope
gradients are 40 to 60 percent. They make up 91 percent
of the unit. The remaining 9 percent consists of boulders
and the shallow, well drained, acid Guayama soils.
Because of the low rainfall of the area, most of the soils
are in native guineagrass and brush. Clean tilled crops
are not suited because of the slopes, depth to rock, and
moisture deficiency. Most of the plant cover dies during
long periods of drought.

Soils formed in residuum from intrusive igneous rocks
This unit is in the southeastern part of the survey area
near the town of San Lorenzo. The soils formed mainly in
the residuum of granitic rocks. Most are steep and very
steep. The landscape is mountainous, with V-shaped
drainageways dissecting the entire area and with narrow,
knife-like ridges, gullies, and slips. Some of the soils are
planted to clean cultivated food crops, but many are in
native and improved pasture. Most soils in this unit have
low potential for crops because of the steep slopes and
shallow depth to the granitic rock.

5. Pandura-Lirios
Shallow to deep, moderately steep to very steep, well
drained soils of the humid mountainous areas
This unit, one of the smaller, makes up 7 percent of the
total acreage of the soil survey area. It is in the vicinity
of San Lorenzo. The soils formed in the residuum of
granitic rock that is part of the San Lorenzo Batholith.
The landscape is mountainous and is highly dissected by
numerous intermittent streams. Narrow ridges, gullies,
and slip areas are common.
The Pandura soils are shallow to weathered granitic
rocks, well drained, loamy, moderately steep to steep.
They are on side slopes of the granitic uplands where
slope gradients are 12 to 60 percent. They make up about
.62 percent of the unit.
The Lirios soils are deep, but highly weathered granitic
rock is at a depth of 20 to 34 inches. These are well
drained, steep to very steep soils with a clayey subsoil.
They are on side slopes and narrow ridgetops where slope
gradients are 20 to 60 percent. They make up 26 percent
of the unit.
The remaining 12 percent of the unit is made up of the
deep, well drained, clayey Limones and Jagueyes soils and
the somewhat poorly drained, clayey Cayagua soils. The
Limones and Jagueyes soils are on side slopes and narrow
ridgetops where slope gradients are 20 to 60 percent.
This unit in general has severe limitations for farming
because of the slope, erosion hazard, and low fertility of
the soils. It has been intensively cultivated for food crops.
Some areas are in improved pasture. Others are in brush
and brushy pasture.
Steep slopes and the erosion hazard are permanent
limitations that preclude the use of these soils for clean
cultivated crops. The slope is a severe limitation for non-






SAN JUAN AREA, PUERTO RICO


farm uses such as dwellings, septic tanks, recreational
areas, and other intensive developments.

Soils formed in residuum from limestone
This unit is in the northwestern part of the survey
area. The soils formed mainly in clayey materials
weathered from limestone. Many are steep and very
steep. Some are nearly level to sloping. The landscape has
a karst topography, which is characterized by haystack
hills, locally known as "mogotes;" sinkholes; and un-
derground drainage. Most of the soils are in brushy
forest. Others are in native and improved pasture. The
soils have low potential for clean cultivated crops.

6. Tanama-Colinas-Soller
Shallow to moderately deep, moderately steep to very
steep, well drained soils of the humid mountainous areas
This unit makes up 4 percent of the total acreage of the
survey area. The landscape is one of karst topography
characterized by the brush-covered "mogotes," or
haystack hills. This unit is in the northwestern part of the
survey area, between the northern coastal plains and the
uplands. The soils of this unit are severely limited for
farming because of the steep slopes and the shallow to
moderate depth to limestone rock. Some have been
cleared of brushy vegetation and planted to pangolagrass.
A large part, however, is still in brush and brushy
pasture.
The Tanama soils are shallow, are well drained, and
have a clayey subsoil. They have slope gradients of 20 to
60 percent. They make up 39 percent of the unit.
The Colinas soils are moderately deep to mixed soft
limestone, are well drained, and have a clayey subsoil.
They have slope gradients of 12 to 60 percent. They make
up 29 percent of the unit.
The Soller soils are shallow to hard fragmental
limestone, are well drained, and have a thin clayey sub-
soil. They have slope gradients of 20 to 60 percent. They
make up 28 percent of the unit.
The remaining 4 percent of the unit consists of the
deep, well drained, clayey Juncal soils and areas of
limestone rockland.

Soils formed in transported materials
Most of these units are in the northern part of the soil
survey area. Some are in inner valleys in the central part.
The soils formed mainly in clayey sediments of mixed
origin and in organic materials. They are mainly nearly
level to sloping. They are on the coastal plains, on flood
plains, in inner valleys, and in low depressional and
lagoonlike positions. Many are planted to clean cultivated
crops to which they are well suited. Soils in the Martin
Pena-Saladar-Hydraquents unit, however, are very poorly
drained and are therefore limited for farming.


7. Almirante-Vega Alta-Matanzas
Deep, gently sloping to sloping, well drained soils on ter-
races and alluvial fans of the coastal plain
This unit occupies 3 percent of the total acreage. It con-
sists of gently sloping to sloping soils on coastal plains, on
terraces, and in valleys between the limestone hills. It is
in the northern section of the survey area.
The Almirante soils are deep, well drained, and clayey.
They are on coastal plains where slope gradients are 2 to
12 percent. They make up about 55 percent of the unit.
The Vega Alta soils are deep, well drained, and clayey.
They are gently sloping to sloping. They are on coastal
plains and terraces where slope gradients are 2 to 12 per-
cent. They make up about 21 percent of the unit.
The Matanzas soils are deep, well drained, and clayey.
They are on foot slopes and in small valleys between the
limestone hills. They have slope gradients of 2 to 5 per-
cent. They make up about 11 percent of the unit.
The remaining 13 percent of the unit is made up of the
deep, gently sloping, well drained, clayey Bayamon and
Torres soils. These soils are on coastal plain terraces and
alluvial fans.
This unit is suited to farming. Most of it was used for
sugarcane but is now in improved pasture such as pan-
golagrass and stargrass. The soils of this unit should be
limed, fertilized, and worked at the proper moisture con-
dition to prevent puddling. They receive adequate
moisture throughout the year for the crops commonly
grown. For nonfarm uses, they have only slight limita-
tions.

8. Toa-Bajura-Coloso
Deep, nearly level, well drained to poorly drained soils on
flood plains
This unit is in the northern part of the survey area.
The soils formed in mixed sediments derived from miscel-
laneous volcanic rocks and deposited over nearly level
river flood plains. They receive adequate moisture
throughout the year for the cultivated crops commonly
grown. Most of these soils were intensively cultivated for
sugarcane. The trend now is toward improved pasture,
such as pangolagrass and stargrass. This unit makes up 4
percent of the total acreage of the survey area.
The Toa soils are deep, are moderately well drained to
well drained, are moderately permeable, and have a
clayey subsoil. They make up 32 percent of the unit.
The Bajura soils are deep, are poorly drained, are
slowly permeable, and have a clayey subsoil. They make
up 27 percent of the unit.
The Coloso soils are deep, somewhat poorly drained,
slowly permeable soils with a clayey subsoil. They make
up 17 percent of the unit.
The remaining 24 percent of the unit consists of the
nearly level, moderately deep, moderately permeable
Estacion soils and the deep, well drained, sandy Reilly
soils and areas of riverwash.






SAN JUAN AREA, PUERTO RICO


farm uses such as dwellings, septic tanks, recreational
areas, and other intensive developments.

Soils formed in residuum from limestone
This unit is in the northwestern part of the survey
area. The soils formed mainly in clayey materials
weathered from limestone. Many are steep and very
steep. Some are nearly level to sloping. The landscape has
a karst topography, which is characterized by haystack
hills, locally known as "mogotes;" sinkholes; and un-
derground drainage. Most of the soils are in brushy
forest. Others are in native and improved pasture. The
soils have low potential for clean cultivated crops.

6. Tanama-Colinas-Soller
Shallow to moderately deep, moderately steep to very
steep, well drained soils of the humid mountainous areas
This unit makes up 4 percent of the total acreage of the
survey area. The landscape is one of karst topography
characterized by the brush-covered "mogotes," or
haystack hills. This unit is in the northwestern part of the
survey area, between the northern coastal plains and the
uplands. The soils of this unit are severely limited for
farming because of the steep slopes and the shallow to
moderate depth to limestone rock. Some have been
cleared of brushy vegetation and planted to pangolagrass.
A large part, however, is still in brush and brushy
pasture.
The Tanama soils are shallow, are well drained, and
have a clayey subsoil. They have slope gradients of 20 to
60 percent. They make up 39 percent of the unit.
The Colinas soils are moderately deep to mixed soft
limestone, are well drained, and have a clayey subsoil.
They have slope gradients of 12 to 60 percent. They make
up 29 percent of the unit.
The Soller soils are shallow to hard fragmental
limestone, are well drained, and have a thin clayey sub-
soil. They have slope gradients of 20 to 60 percent. They
make up 28 percent of the unit.
The remaining 4 percent of the unit consists of the
deep, well drained, clayey Juncal soils and areas of
limestone rockland.

Soils formed in transported materials
Most of these units are in the northern part of the soil
survey area. Some are in inner valleys in the central part.
The soils formed mainly in clayey sediments of mixed
origin and in organic materials. They are mainly nearly
level to sloping. They are on the coastal plains, on flood
plains, in inner valleys, and in low depressional and
lagoonlike positions. Many are planted to clean cultivated
crops to which they are well suited. Soils in the Martin
Pena-Saladar-Hydraquents unit, however, are very poorly
drained and are therefore limited for farming.


7. Almirante-Vega Alta-Matanzas
Deep, gently sloping to sloping, well drained soils on ter-
races and alluvial fans of the coastal plain
This unit occupies 3 percent of the total acreage. It con-
sists of gently sloping to sloping soils on coastal plains, on
terraces, and in valleys between the limestone hills. It is
in the northern section of the survey area.
The Almirante soils are deep, well drained, and clayey.
They are on coastal plains where slope gradients are 2 to
12 percent. They make up about 55 percent of the unit.
The Vega Alta soils are deep, well drained, and clayey.
They are gently sloping to sloping. They are on coastal
plains and terraces where slope gradients are 2 to 12 per-
cent. They make up about 21 percent of the unit.
The Matanzas soils are deep, well drained, and clayey.
They are on foot slopes and in small valleys between the
limestone hills. They have slope gradients of 2 to 5 per-
cent. They make up about 11 percent of the unit.
The remaining 13 percent of the unit is made up of the
deep, gently sloping, well drained, clayey Bayamon and
Torres soils. These soils are on coastal plain terraces and
alluvial fans.
This unit is suited to farming. Most of it was used for
sugarcane but is now in improved pasture such as pan-
golagrass and stargrass. The soils of this unit should be
limed, fertilized, and worked at the proper moisture con-
dition to prevent puddling. They receive adequate
moisture throughout the year for the crops commonly
grown. For nonfarm uses, they have only slight limita-
tions.

8. Toa-Bajura-Coloso
Deep, nearly level, well drained to poorly drained soils on
flood plains
This unit is in the northern part of the survey area.
The soils formed in mixed sediments derived from miscel-
laneous volcanic rocks and deposited over nearly level
river flood plains. They receive adequate moisture
throughout the year for the cultivated crops commonly
grown. Most of these soils were intensively cultivated for
sugarcane. The trend now is toward improved pasture,
such as pangolagrass and stargrass. This unit makes up 4
percent of the total acreage of the survey area.
The Toa soils are deep, are moderately well drained to
well drained, are moderately permeable, and have a
clayey subsoil. They make up 32 percent of the unit.
The Bajura soils are deep, are poorly drained, are
slowly permeable, and have a clayey subsoil. They make
up 27 percent of the unit.
The Coloso soils are deep, somewhat poorly drained,
slowly permeable soils with a clayey subsoil. They make
up 17 percent of the unit.
The remaining 24 percent of the unit consists of the
nearly level, moderately deep, moderately permeable
Estacion soils and the deep, well drained, sandy Reilly
soils and areas of riverwash.






SAN JUAN AREA, PUERTO RICO


farm uses such as dwellings, septic tanks, recreational
areas, and other intensive developments.

Soils formed in residuum from limestone
This unit is in the northwestern part of the survey
area. The soils formed mainly in clayey materials
weathered from limestone. Many are steep and very
steep. Some are nearly level to sloping. The landscape has
a karst topography, which is characterized by haystack
hills, locally known as "mogotes;" sinkholes; and un-
derground drainage. Most of the soils are in brushy
forest. Others are in native and improved pasture. The
soils have low potential for clean cultivated crops.

6. Tanama-Colinas-Soller
Shallow to moderately deep, moderately steep to very
steep, well drained soils of the humid mountainous areas
This unit makes up 4 percent of the total acreage of the
survey area. The landscape is one of karst topography
characterized by the brush-covered "mogotes," or
haystack hills. This unit is in the northwestern part of the
survey area, between the northern coastal plains and the
uplands. The soils of this unit are severely limited for
farming because of the steep slopes and the shallow to
moderate depth to limestone rock. Some have been
cleared of brushy vegetation and planted to pangolagrass.
A large part, however, is still in brush and brushy
pasture.
The Tanama soils are shallow, are well drained, and
have a clayey subsoil. They have slope gradients of 20 to
60 percent. They make up 39 percent of the unit.
The Colinas soils are moderately deep to mixed soft
limestone, are well drained, and have a clayey subsoil.
They have slope gradients of 12 to 60 percent. They make
up 29 percent of the unit.
The Soller soils are shallow to hard fragmental
limestone, are well drained, and have a thin clayey sub-
soil. They have slope gradients of 20 to 60 percent. They
make up 28 percent of the unit.
The remaining 4 percent of the unit consists of the
deep, well drained, clayey Juncal soils and areas of
limestone rockland.

Soils formed in transported materials
Most of these units are in the northern part of the soil
survey area. Some are in inner valleys in the central part.
The soils formed mainly in clayey sediments of mixed
origin and in organic materials. They are mainly nearly
level to sloping. They are on the coastal plains, on flood
plains, in inner valleys, and in low depressional and
lagoonlike positions. Many are planted to clean cultivated
crops to which they are well suited. Soils in the Martin
Pena-Saladar-Hydraquents unit, however, are very poorly
drained and are therefore limited for farming.


7. Almirante-Vega Alta-Matanzas
Deep, gently sloping to sloping, well drained soils on ter-
races and alluvial fans of the coastal plain
This unit occupies 3 percent of the total acreage. It con-
sists of gently sloping to sloping soils on coastal plains, on
terraces, and in valleys between the limestone hills. It is
in the northern section of the survey area.
The Almirante soils are deep, well drained, and clayey.
They are on coastal plains where slope gradients are 2 to
12 percent. They make up about 55 percent of the unit.
The Vega Alta soils are deep, well drained, and clayey.
They are gently sloping to sloping. They are on coastal
plains and terraces where slope gradients are 2 to 12 per-
cent. They make up about 21 percent of the unit.
The Matanzas soils are deep, well drained, and clayey.
They are on foot slopes and in small valleys between the
limestone hills. They have slope gradients of 2 to 5 per-
cent. They make up about 11 percent of the unit.
The remaining 13 percent of the unit is made up of the
deep, gently sloping, well drained, clayey Bayamon and
Torres soils. These soils are on coastal plain terraces and
alluvial fans.
This unit is suited to farming. Most of it was used for
sugarcane but is now in improved pasture such as pan-
golagrass and stargrass. The soils of this unit should be
limed, fertilized, and worked at the proper moisture con-
dition to prevent puddling. They receive adequate
moisture throughout the year for the crops commonly
grown. For nonfarm uses, they have only slight limita-
tions.

8. Toa-Bajura-Coloso
Deep, nearly level, well drained to poorly drained soils on
flood plains
This unit is in the northern part of the survey area.
The soils formed in mixed sediments derived from miscel-
laneous volcanic rocks and deposited over nearly level
river flood plains. They receive adequate moisture
throughout the year for the cultivated crops commonly
grown. Most of these soils were intensively cultivated for
sugarcane. The trend now is toward improved pasture,
such as pangolagrass and stargrass. This unit makes up 4
percent of the total acreage of the survey area.
The Toa soils are deep, are moderately well drained to
well drained, are moderately permeable, and have a
clayey subsoil. They make up 32 percent of the unit.
The Bajura soils are deep, are poorly drained, are
slowly permeable, and have a clayey subsoil. They make
up 27 percent of the unit.
The Coloso soils are deep, somewhat poorly drained,
slowly permeable soils with a clayey subsoil. They make
up 17 percent of the unit.
The remaining 24 percent of the unit consists of the
nearly level, moderately deep, moderately permeable
Estacion soils and the deep, well drained, sandy Reilly
soils and areas of riverwash.






SAN JUAN AREA, PUERTO RICO


farm uses such as dwellings, septic tanks, recreational
areas, and other intensive developments.

Soils formed in residuum from limestone
This unit is in the northwestern part of the survey
area. The soils formed mainly in clayey materials
weathered from limestone. Many are steep and very
steep. Some are nearly level to sloping. The landscape has
a karst topography, which is characterized by haystack
hills, locally known as "mogotes;" sinkholes; and un-
derground drainage. Most of the soils are in brushy
forest. Others are in native and improved pasture. The
soils have low potential for clean cultivated crops.

6. Tanama-Colinas-Soller
Shallow to moderately deep, moderately steep to very
steep, well drained soils of the humid mountainous areas
This unit makes up 4 percent of the total acreage of the
survey area. The landscape is one of karst topography
characterized by the brush-covered "mogotes," or
haystack hills. This unit is in the northwestern part of the
survey area, between the northern coastal plains and the
uplands. The soils of this unit are severely limited for
farming because of the steep slopes and the shallow to
moderate depth to limestone rock. Some have been
cleared of brushy vegetation and planted to pangolagrass.
A large part, however, is still in brush and brushy
pasture.
The Tanama soils are shallow, are well drained, and
have a clayey subsoil. They have slope gradients of 20 to
60 percent. They make up 39 percent of the unit.
The Colinas soils are moderately deep to mixed soft
limestone, are well drained, and have a clayey subsoil.
They have slope gradients of 12 to 60 percent. They make
up 29 percent of the unit.
The Soller soils are shallow to hard fragmental
limestone, are well drained, and have a thin clayey sub-
soil. They have slope gradients of 20 to 60 percent. They
make up 28 percent of the unit.
The remaining 4 percent of the unit consists of the
deep, well drained, clayey Juncal soils and areas of
limestone rockland.

Soils formed in transported materials
Most of these units are in the northern part of the soil
survey area. Some are in inner valleys in the central part.
The soils formed mainly in clayey sediments of mixed
origin and in organic materials. They are mainly nearly
level to sloping. They are on the coastal plains, on flood
plains, in inner valleys, and in low depressional and
lagoonlike positions. Many are planted to clean cultivated
crops to which they are well suited. Soils in the Martin
Pena-Saladar-Hydraquents unit, however, are very poorly
drained and are therefore limited for farming.


7. Almirante-Vega Alta-Matanzas
Deep, gently sloping to sloping, well drained soils on ter-
races and alluvial fans of the coastal plain
This unit occupies 3 percent of the total acreage. It con-
sists of gently sloping to sloping soils on coastal plains, on
terraces, and in valleys between the limestone hills. It is
in the northern section of the survey area.
The Almirante soils are deep, well drained, and clayey.
They are on coastal plains where slope gradients are 2 to
12 percent. They make up about 55 percent of the unit.
The Vega Alta soils are deep, well drained, and clayey.
They are gently sloping to sloping. They are on coastal
plains and terraces where slope gradients are 2 to 12 per-
cent. They make up about 21 percent of the unit.
The Matanzas soils are deep, well drained, and clayey.
They are on foot slopes and in small valleys between the
limestone hills. They have slope gradients of 2 to 5 per-
cent. They make up about 11 percent of the unit.
The remaining 13 percent of the unit is made up of the
deep, gently sloping, well drained, clayey Bayamon and
Torres soils. These soils are on coastal plain terraces and
alluvial fans.
This unit is suited to farming. Most of it was used for
sugarcane but is now in improved pasture such as pan-
golagrass and stargrass. The soils of this unit should be
limed, fertilized, and worked at the proper moisture con-
dition to prevent puddling. They receive adequate
moisture throughout the year for the crops commonly
grown. For nonfarm uses, they have only slight limita-
tions.

8. Toa-Bajura-Coloso
Deep, nearly level, well drained to poorly drained soils on
flood plains
This unit is in the northern part of the survey area.
The soils formed in mixed sediments derived from miscel-
laneous volcanic rocks and deposited over nearly level
river flood plains. They receive adequate moisture
throughout the year for the cultivated crops commonly
grown. Most of these soils were intensively cultivated for
sugarcane. The trend now is toward improved pasture,
such as pangolagrass and stargrass. This unit makes up 4
percent of the total acreage of the survey area.
The Toa soils are deep, are moderately well drained to
well drained, are moderately permeable, and have a
clayey subsoil. They make up 32 percent of the unit.
The Bajura soils are deep, are poorly drained, are
slowly permeable, and have a clayey subsoil. They make
up 27 percent of the unit.
The Coloso soils are deep, somewhat poorly drained,
slowly permeable soils with a clayey subsoil. They make
up 17 percent of the unit.
The remaining 24 percent of the unit consists of the
nearly level, moderately deep, moderately permeable
Estacion soils and the deep, well drained, sandy Reilly
soils and areas of riverwash.






SAN JUAN AREA, PUERTO RICO


farm uses such as dwellings, septic tanks, recreational
areas, and other intensive developments.

Soils formed in residuum from limestone
This unit is in the northwestern part of the survey
area. The soils formed mainly in clayey materials
weathered from limestone. Many are steep and very
steep. Some are nearly level to sloping. The landscape has
a karst topography, which is characterized by haystack
hills, locally known as "mogotes;" sinkholes; and un-
derground drainage. Most of the soils are in brushy
forest. Others are in native and improved pasture. The
soils have low potential for clean cultivated crops.

6. Tanama-Colinas-Soller
Shallow to moderately deep, moderately steep to very
steep, well drained soils of the humid mountainous areas
This unit makes up 4 percent of the total acreage of the
survey area. The landscape is one of karst topography
characterized by the brush-covered "mogotes," or
haystack hills. This unit is in the northwestern part of the
survey area, between the northern coastal plains and the
uplands. The soils of this unit are severely limited for
farming because of the steep slopes and the shallow to
moderate depth to limestone rock. Some have been
cleared of brushy vegetation and planted to pangolagrass.
A large part, however, is still in brush and brushy
pasture.
The Tanama soils are shallow, are well drained, and
have a clayey subsoil. They have slope gradients of 20 to
60 percent. They make up 39 percent of the unit.
The Colinas soils are moderately deep to mixed soft
limestone, are well drained, and have a clayey subsoil.
They have slope gradients of 12 to 60 percent. They make
up 29 percent of the unit.
The Soller soils are shallow to hard fragmental
limestone, are well drained, and have a thin clayey sub-
soil. They have slope gradients of 20 to 60 percent. They
make up 28 percent of the unit.
The remaining 4 percent of the unit consists of the
deep, well drained, clayey Juncal soils and areas of
limestone rockland.

Soils formed in transported materials
Most of these units are in the northern part of the soil
survey area. Some are in inner valleys in the central part.
The soils formed mainly in clayey sediments of mixed
origin and in organic materials. They are mainly nearly
level to sloping. They are on the coastal plains, on flood
plains, in inner valleys, and in low depressional and
lagoonlike positions. Many are planted to clean cultivated
crops to which they are well suited. Soils in the Martin
Pena-Saladar-Hydraquents unit, however, are very poorly
drained and are therefore limited for farming.


7. Almirante-Vega Alta-Matanzas
Deep, gently sloping to sloping, well drained soils on ter-
races and alluvial fans of the coastal plain
This unit occupies 3 percent of the total acreage. It con-
sists of gently sloping to sloping soils on coastal plains, on
terraces, and in valleys between the limestone hills. It is
in the northern section of the survey area.
The Almirante soils are deep, well drained, and clayey.
They are on coastal plains where slope gradients are 2 to
12 percent. They make up about 55 percent of the unit.
The Vega Alta soils are deep, well drained, and clayey.
They are gently sloping to sloping. They are on coastal
plains and terraces where slope gradients are 2 to 12 per-
cent. They make up about 21 percent of the unit.
The Matanzas soils are deep, well drained, and clayey.
They are on foot slopes and in small valleys between the
limestone hills. They have slope gradients of 2 to 5 per-
cent. They make up about 11 percent of the unit.
The remaining 13 percent of the unit is made up of the
deep, gently sloping, well drained, clayey Bayamon and
Torres soils. These soils are on coastal plain terraces and
alluvial fans.
This unit is suited to farming. Most of it was used for
sugarcane but is now in improved pasture such as pan-
golagrass and stargrass. The soils of this unit should be
limed, fertilized, and worked at the proper moisture con-
dition to prevent puddling. They receive adequate
moisture throughout the year for the crops commonly
grown. For nonfarm uses, they have only slight limita-
tions.

8. Toa-Bajura-Coloso
Deep, nearly level, well drained to poorly drained soils on
flood plains
This unit is in the northern part of the survey area.
The soils formed in mixed sediments derived from miscel-
laneous volcanic rocks and deposited over nearly level
river flood plains. They receive adequate moisture
throughout the year for the cultivated crops commonly
grown. Most of these soils were intensively cultivated for
sugarcane. The trend now is toward improved pasture,
such as pangolagrass and stargrass. This unit makes up 4
percent of the total acreage of the survey area.
The Toa soils are deep, are moderately well drained to
well drained, are moderately permeable, and have a
clayey subsoil. They make up 32 percent of the unit.
The Bajura soils are deep, are poorly drained, are
slowly permeable, and have a clayey subsoil. They make
up 27 percent of the unit.
The Coloso soils are deep, somewhat poorly drained,
slowly permeable soils with a clayey subsoil. They make
up 17 percent of the unit.
The remaining 24 percent of the unit consists of the
nearly level, moderately deep, moderately permeable
Estacion soils and the deep, well drained, sandy Reilly
soils and areas of riverwash.






SOIL SURVEY


These soils have severe limitations for nonfarm uses
such as dwellings, septic tanks, and roads because of poor
drainage and the flood hazard.

9. Mabi-Rio Arriba
Deep, nearly level to sloping, moderately well drained to
somewhat poorly drained soils on terraces, footslopes, and
alluvial fans of inner valleys
This unit is in the east-central part of the survey area.
The soils formed in fine textured sediments of mixed
origin. They receive adequate moisture throughout the
year for most crops.
This small unit makes up 2 percent of the total acreage
of the survey area. Most of the soils were used for sugar-
cane production. The trend now is toward improved
pasture, such as pangolagrass.
The mabi soils are deep, somewhat poorly drained,
slowly permeable, clayey soils. They have slope gradients
of 0 to 12 percent. They make up 54 percent of the unit.
The Rio Arriba soils are deep, moderately well drained,
moderately slowly permeable soils with a clayey subsoil.
They have slope gradients of 2 to 12 percent. They make
up 41 percent of the unit.
The remaining 5 percent is the deep, poorly drained,
clayey Montegrande soil.
The soils of this unit have severe limitations for non-
farm uses because of their clayey nature and high shrink-
swell potential.

10. Martin Pena-Saladar-Hydraquents
Deep, nearly level, very poorly drained soils in low
depressions and lagoons of the coastal plain
This unit occupies 1 percent of the total acreage of the
survey area. The landscape consists of low-lying depres-
sions filled with water most of the year. This unit is in
the northwestern part of the coastal plain, in the vicinity
of Dorado.
The Martin Pena soils are deep and very poorly
drained. They have a thin surface layer of muck underlain
by clayey material. They make up 51 percent of the unit.
The Saladar soils are deep, very poorly drained muck.
They make up about 23 percent of the unit.
Hydraquents formed in variable materials in tidal
marshes that are permanently saturated with brackish
water. These soils have no sulfidic materials within 50
centimeters of the mineral surface. They make up 12 per-
cent of the unit.
The remaining 14 percent of the unit is made up of the
deep, excessively drained Catano and Durados soils.
These soils occupy a nearly level area of the coastal plain
in the northwestern part of the survey area.
These soils have severe limitations for farming because
of very poor drainage. Complex drainage practices are
needed if they are to be reclaimed. For nonfarm uses,
they also have severe limitations because of very poor
drainage and low bearing capacity. It is necessary to sink
pilings and use other complex engineering practices.


The soils of this unit are in an area of intensive
development, and most of this area is being reclaimed for
dwellings.


Soil maps for detailed planning

The map units shown on the detailed soil maps at the
back of this publication represent the kinds of soil in the
survey area. They are described in this section. The
descriptions together with the soil maps can be useful in
determining the potential of a soil and in managing it for
food and fiber production; in planning land use and
developing soil resources; and in enhancing, protecting,
and preserving the environment. More information for
each map unit, or soil, is given in the section "Use and
management of the soils."
Preceding the name of each map unit is the symbol that
identifies the soil on the detailed soil maps. Each soil
description includes general facts about the soil and a
brief description of the soil profile. In each description,
the principal hazards and limitations are indicated, and
the management concerns and practices needed are
discussed.
The map units on the detailed soil maps represent an
area on the landscape made up mostly of the soil or soils
for which the unit is named. Most of the delineations
shown on the detailed soil map are phases of soil series.

Soils that have a profile that is almost alike make up a
soil series. Except for allowable differences in texture of
the surface layer or of the underlying substratum, all the
soils of a series have major horizons that are similar in
composition, thickness, and arrangement in the profile. A
soil series commonly is named for a town or geographic
feature near the place where a soil of that series was
first observed and mapped.
Soils of one series can differ in texture of the surface
layer or in the underlying substratum and in slope, ero-
sion, stoniness, salinity, wetness, or other characteristics
that affect their use. On the basis of such differences, a
soil series is divided into phases. The name of a soil phase
commonly indicates a feature that affects use or manage-
ment. For example, Colinas clay loam is one of several
phases within the Colinas series.
Some map units are made up of two or more dominant
kinds of soil. Such map units are called soil complexes,
soil associations, and undifferentiated groups.
A soil complex consists of areas of two or more soils
that are so intricately mixed or so small in size that they
cannot be shown separately on the soil map. Each area in-
cludes some of each of the two or more dominant soils,
and the pattern and proportion are somewhat similar in
all areas. Urbanland-Mucara complex is an example.
A soil association is made up of soils that are geo-
graphically associated and are shown as one unit on the
map because it is not practical to separate them. A soil
association has considerable regularity in geographic pat-
tern and in the kinds of soil that are a part of it. The ex-






SOIL SURVEY


These soils have severe limitations for nonfarm uses
such as dwellings, septic tanks, and roads because of poor
drainage and the flood hazard.

9. Mabi-Rio Arriba
Deep, nearly level to sloping, moderately well drained to
somewhat poorly drained soils on terraces, footslopes, and
alluvial fans of inner valleys
This unit is in the east-central part of the survey area.
The soils formed in fine textured sediments of mixed
origin. They receive adequate moisture throughout the
year for most crops.
This small unit makes up 2 percent of the total acreage
of the survey area. Most of the soils were used for sugar-
cane production. The trend now is toward improved
pasture, such as pangolagrass.
The mabi soils are deep, somewhat poorly drained,
slowly permeable, clayey soils. They have slope gradients
of 0 to 12 percent. They make up 54 percent of the unit.
The Rio Arriba soils are deep, moderately well drained,
moderately slowly permeable soils with a clayey subsoil.
They have slope gradients of 2 to 12 percent. They make
up 41 percent of the unit.
The remaining 5 percent is the deep, poorly drained,
clayey Montegrande soil.
The soils of this unit have severe limitations for non-
farm uses because of their clayey nature and high shrink-
swell potential.

10. Martin Pena-Saladar-Hydraquents
Deep, nearly level, very poorly drained soils in low
depressions and lagoons of the coastal plain
This unit occupies 1 percent of the total acreage of the
survey area. The landscape consists of low-lying depres-
sions filled with water most of the year. This unit is in
the northwestern part of the coastal plain, in the vicinity
of Dorado.
The Martin Pena soils are deep and very poorly
drained. They have a thin surface layer of muck underlain
by clayey material. They make up 51 percent of the unit.
The Saladar soils are deep, very poorly drained muck.
They make up about 23 percent of the unit.
Hydraquents formed in variable materials in tidal
marshes that are permanently saturated with brackish
water. These soils have no sulfidic materials within 50
centimeters of the mineral surface. They make up 12 per-
cent of the unit.
The remaining 14 percent of the unit is made up of the
deep, excessively drained Catano and Durados soils.
These soils occupy a nearly level area of the coastal plain
in the northwestern part of the survey area.
These soils have severe limitations for farming because
of very poor drainage. Complex drainage practices are
needed if they are to be reclaimed. For nonfarm uses,
they also have severe limitations because of very poor
drainage and low bearing capacity. It is necessary to sink
pilings and use other complex engineering practices.


The soils of this unit are in an area of intensive
development, and most of this area is being reclaimed for
dwellings.


Soil maps for detailed planning

The map units shown on the detailed soil maps at the
back of this publication represent the kinds of soil in the
survey area. They are described in this section. The
descriptions together with the soil maps can be useful in
determining the potential of a soil and in managing it for
food and fiber production; in planning land use and
developing soil resources; and in enhancing, protecting,
and preserving the environment. More information for
each map unit, or soil, is given in the section "Use and
management of the soils."
Preceding the name of each map unit is the symbol that
identifies the soil on the detailed soil maps. Each soil
description includes general facts about the soil and a
brief description of the soil profile. In each description,
the principal hazards and limitations are indicated, and
the management concerns and practices needed are
discussed.
The map units on the detailed soil maps represent an
area on the landscape made up mostly of the soil or soils
for which the unit is named. Most of the delineations
shown on the detailed soil map are phases of soil series.

Soils that have a profile that is almost alike make up a
soil series. Except for allowable differences in texture of
the surface layer or of the underlying substratum, all the
soils of a series have major horizons that are similar in
composition, thickness, and arrangement in the profile. A
soil series commonly is named for a town or geographic
feature near the place where a soil of that series was
first observed and mapped.
Soils of one series can differ in texture of the surface
layer or in the underlying substratum and in slope, ero-
sion, stoniness, salinity, wetness, or other characteristics
that affect their use. On the basis of such differences, a
soil series is divided into phases. The name of a soil phase
commonly indicates a feature that affects use or manage-
ment. For example, Colinas clay loam is one of several
phases within the Colinas series.
Some map units are made up of two or more dominant
kinds of soil. Such map units are called soil complexes,
soil associations, and undifferentiated groups.
A soil complex consists of areas of two or more soils
that are so intricately mixed or so small in size that they
cannot be shown separately on the soil map. Each area in-
cludes some of each of the two or more dominant soils,
and the pattern and proportion are somewhat similar in
all areas. Urbanland-Mucara complex is an example.
A soil association is made up of soils that are geo-
graphically associated and are shown as one unit on the
map because it is not practical to separate them. A soil
association has considerable regularity in geographic pat-
tern and in the kinds of soil that are a part of it. The ex-






SOIL SURVEY


These soils have severe limitations for nonfarm uses
such as dwellings, septic tanks, and roads because of poor
drainage and the flood hazard.

9. Mabi-Rio Arriba
Deep, nearly level to sloping, moderately well drained to
somewhat poorly drained soils on terraces, footslopes, and
alluvial fans of inner valleys
This unit is in the east-central part of the survey area.
The soils formed in fine textured sediments of mixed
origin. They receive adequate moisture throughout the
year for most crops.
This small unit makes up 2 percent of the total acreage
of the survey area. Most of the soils were used for sugar-
cane production. The trend now is toward improved
pasture, such as pangolagrass.
The mabi soils are deep, somewhat poorly drained,
slowly permeable, clayey soils. They have slope gradients
of 0 to 12 percent. They make up 54 percent of the unit.
The Rio Arriba soils are deep, moderately well drained,
moderately slowly permeable soils with a clayey subsoil.
They have slope gradients of 2 to 12 percent. They make
up 41 percent of the unit.
The remaining 5 percent is the deep, poorly drained,
clayey Montegrande soil.
The soils of this unit have severe limitations for non-
farm uses because of their clayey nature and high shrink-
swell potential.

10. Martin Pena-Saladar-Hydraquents
Deep, nearly level, very poorly drained soils in low
depressions and lagoons of the coastal plain
This unit occupies 1 percent of the total acreage of the
survey area. The landscape consists of low-lying depres-
sions filled with water most of the year. This unit is in
the northwestern part of the coastal plain, in the vicinity
of Dorado.
The Martin Pena soils are deep and very poorly
drained. They have a thin surface layer of muck underlain
by clayey material. They make up 51 percent of the unit.
The Saladar soils are deep, very poorly drained muck.
They make up about 23 percent of the unit.
Hydraquents formed in variable materials in tidal
marshes that are permanently saturated with brackish
water. These soils have no sulfidic materials within 50
centimeters of the mineral surface. They make up 12 per-
cent of the unit.
The remaining 14 percent of the unit is made up of the
deep, excessively drained Catano and Durados soils.
These soils occupy a nearly level area of the coastal plain
in the northwestern part of the survey area.
These soils have severe limitations for farming because
of very poor drainage. Complex drainage practices are
needed if they are to be reclaimed. For nonfarm uses,
they also have severe limitations because of very poor
drainage and low bearing capacity. It is necessary to sink
pilings and use other complex engineering practices.


The soils of this unit are in an area of intensive
development, and most of this area is being reclaimed for
dwellings.


Soil maps for detailed planning

The map units shown on the detailed soil maps at the
back of this publication represent the kinds of soil in the
survey area. They are described in this section. The
descriptions together with the soil maps can be useful in
determining the potential of a soil and in managing it for
food and fiber production; in planning land use and
developing soil resources; and in enhancing, protecting,
and preserving the environment. More information for
each map unit, or soil, is given in the section "Use and
management of the soils."
Preceding the name of each map unit is the symbol that
identifies the soil on the detailed soil maps. Each soil
description includes general facts about the soil and a
brief description of the soil profile. In each description,
the principal hazards and limitations are indicated, and
the management concerns and practices needed are
discussed.
The map units on the detailed soil maps represent an
area on the landscape made up mostly of the soil or soils
for which the unit is named. Most of the delineations
shown on the detailed soil map are phases of soil series.

Soils that have a profile that is almost alike make up a
soil series. Except for allowable differences in texture of
the surface layer or of the underlying substratum, all the
soils of a series have major horizons that are similar in
composition, thickness, and arrangement in the profile. A
soil series commonly is named for a town or geographic
feature near the place where a soil of that series was
first observed and mapped.
Soils of one series can differ in texture of the surface
layer or in the underlying substratum and in slope, ero-
sion, stoniness, salinity, wetness, or other characteristics
that affect their use. On the basis of such differences, a
soil series is divided into phases. The name of a soil phase
commonly indicates a feature that affects use or manage-
ment. For example, Colinas clay loam is one of several
phases within the Colinas series.
Some map units are made up of two or more dominant
kinds of soil. Such map units are called soil complexes,
soil associations, and undifferentiated groups.
A soil complex consists of areas of two or more soils
that are so intricately mixed or so small in size that they
cannot be shown separately on the soil map. Each area in-
cludes some of each of the two or more dominant soils,
and the pattern and proportion are somewhat similar in
all areas. Urbanland-Mucara complex is an example.
A soil association is made up of soils that are geo-
graphically associated and are shown as one unit on the
map because it is not practical to separate them. A soil
association has considerable regularity in geographic pat-
tern and in the kinds of soil that are a part of it. The ex-






SAN JUAN AREA, PUERTO RICO


tent of the soils can differ appreciably from one delinea-
tion to another; nevertheless, interpretations can be made
for use and management of the soils.
An undifferentiated group is made up of two or more
soils that could be mapped individually but are mapped as
one unit because there is little value in separating them.
The pattern and proportion of the soils are not uniform.
An area shown on the map has at least one of the domi-
nant (named) soils or may have all of them.
Most map units include small, scattered areas of soils
other than those that appear in the name of the map unit.
Some of these soils have properties that differ substan-
tially from those of the dominant soil or soils and thus
could significantly affect use and management of the map
unit. These soils are described in the description of each
map unit. Some of the more unusual or strongly contrast-
ing soils that are included are identified by a special sym-
bol on the soil map.
Most mapped areas include places that have little or no
soil material and support little or no vegetation. Such
places are called miscellaneous areas; they are delineated
on the soil map and given descriptive names. Made land is
an example. Some of these areas are too small to be
delineated and are identified by a special symbol on the
soil map.
The acreage and proportionate extent of each map unit
are given in table 4, and additional information on proper-
ties, limitations, capabilities, and potentials for many soil
uses is given for each kind of soil in other tables in this
survey. (See "Summary of tables.") Many of the terms
used in describing soils are defined in the Glossary.

Soil descriptions
AaB-Aceitunas clay, 2 to 5 percent slopes. This is a
gently sloping, well drained soil on terraces and alluvial
fans. Slopes are smooth and are 100 to 500 feet long. The
areas range from 20 to 200 acres.
Typically the surface layer is dark brown friable clay
about 8 inches thick. The subsoil, to a depth of 60 inches,
is yellowish red clay. It is firm to a depth of 30 inches
and is friable from 30 inches to a depth of 60 inches.
Included with this soil in mapping-are some small areas
of Rio Arriba and Lares soils. The surface layer of the
Rio Arriba soils is brown clay and that of the Lares soils
is dark brown clay. These soils make up 10 to 20 percent
of the acreage.
Permeability and the available water capacity are
moderate. Runoff is medium. This soil is medium in natu-
ral fertility and has a deep root zone. It is difficult to
work because of the stickiness and plasticity of the clay.
It should be tilled at the optimum moisture content to
avoid puddling and the formation of large clods. Crops
respond well to heavy applications of fertilizers. Con-
trolling erosion is the major concern of management.
This soil has been used for crops such as sugarcane,
plantains, and taniers. It is best suited, however, to pan-
golagrass, stargrass, and Merker grass.


Proper stocking rates and deferred grazing, as well as
liming and fertilizing, are chief management needs.
This soil is moderately suited to most urban uses
because of its clayey nature. If the soil is used as con-
struction sites, temporary plant cover should be
established quickly in denuded areas. Capability subclass
IIe.
AaC-Aceitunas clay, 5 to 12 percent slopes. This is a
sloping, well drained soil on terraces and alluvial fans.
Slopes are smooth and are 100 to 800 feet long. The areas
range from 10 to 200 acres.
Typically the surface layer is dark brown friable clay
about 8 inches thick. The subsoil, to a depth of 60 inches,
is yellowish red clay. It is firm to a depth of 30 inches
and is friable from 30 inches to a depth of 60 inches.
Included with this soil in mapping are some small areas
of Rio Arriba, Lares, and Via soils. The surface layer of
the Rio Arriba soils is brown clay and that of the Lares
soils is dark brown clay. The surface layer of the Via soils
is dark brown clay loam. These soils make up 15 to 20
percent of the areas of this mapping unit.
Permeability and the available water capacity are
moderate. Runoff is medium. This soil is medium in natu-
ral fertility and has a deep root zone. It is difficult to
work because of the stickiness and plasticity of the clay.
It should be tilled at the optimum moisture content to
avoid puddling and the formation of large clods. Crops
respond well to heavy applications of lime and fertilizers.
Controlling erosion is the major concern of management.
This soil has been used for crops such as sugarcane,
plantains, and taniers. It is suited to pangolagrass, star-
grass, and Merker grass.
Proper stocking rates and deferred grazing, as well as
liming and fertilizing, are chief management needs.
This soil is moderately suited to urban uses because of
the slope and its clayey nature. If the soil is used as con-
struction sites, temporary plant cover should be
established quickly in denuded areas. Capability subclass
IIIe.
AbD-Aibonito clay, 12 to 20 percent slopes. This is a
moderately steep, well drained soil on ridgetops and side
slopes of strongly dissected volcanic uplands. Slopes are
400 to 800 feet long. The areas range from 10 to 50 acres.
Typically the surface layer is dark grayish brown, fria-
ble clay about 7 inches thick. The subsoil is about 36
inches thick; it is strong brown clay mottled with red and
yellowish brown. The substratum, beginning at a depth of
43 inches, is red, strong brown, and white, friable clay
saprolite to a depth of 65 inches and silty clay saprolite
from 65 to 110 inches.
Included with this soil in mapping are small areas of
Humatas, Consumo, and Los Guineos soils. The surface
layer of the Humatas soils is dark brown clay, that of the
Consumo soils is reddish brown clay, and that of the Los
Guineos soils is dark yellowish brown clay. These soils
make up 10 to 20 percent of this mapping unit.
Permeability and the available water capacity are
moderate. Runoff is medium. The soil is medium in natu-







SOIL SURVEY


ral fertility and has a deep root zone. It is difficult to
work because of slope and the stickiness and plasticity of
the clay. Crops respond well to heavy applications of lime
and fertilizers. Controlling erosion is the major concern of
management.
This soil has been used for such crops as plantains,
taniers, and yams. It is suited to pangolagrass, stargrass,
and Merker grass.
Proper stocking rates and deferred grazing, as well as
liming and fertilizing, are chief management needs.
This soil is suited to Honduras pine, mahogany, kadam,
mahoe, and eucalyptus trees. Production of Honduras pine
is moderate, about 1100 board feet per acre per year. The
hazard of erosion and limitations in the use of equipment
are the major concerns of management. Logging roads,
skid trails, and planting should be on the contour to help
control erosion. The use of logging equipment is
restricted at times because the soil is soft and slippery
when wet. Brush removal, careful hand planting, and fer-
tilizing increase the survival of planted seedlings.
This soil is limited for most urban uses because it is
moderately steep and subject to landslides. If the soil is
used for construction sites, development should be on the
contour. Removal of vegetation should be held to a
minimum, and a temporary plant cover established
quickly in denuded areas. Capability subclass IVe.
AbE-Aibonito clay, 20 to 40 percent slopes. This is a
steep, well drained soil on ridgetops and side slopes of
strongly dissected uplands. Slopes are 400 to 1000 feet
long. The areas range from 10 to 200 acres.
Typically the surface layer is dark grayish brown, fria-
ble clay about 7 inches thick. The subsoil is about 36
inches thick; it is strong brown clay mottled with red and
yellowish brown. The substratum, beginning at a depth of
43 inches, is red, strong brown, and white, friable clay
saprolite to a depth of 65 inches and silty clay saprolite
from 65 to 110 inches.
Included with this soil in mapping are small areas of
Humatas, Consumo, and Los Guineos soils. The surface
layer of the Humatas soils is dark brown clay; that of the
Consumo soils is reddish brown clay; and that of the Los
Guineos is dark yellowish brown clay. These soils make
up 15 to 20 percent of this mapping unit.
Permeability and the available water capacity are
moderate. Runoff is rapid, and erosion is a hazard. This
soil is medium in natural fertility, and it has a deep root
zone. Slippage is common in roadbanks, ditches, and
drainageways. This soil is difficult to work because it is
very steep and because of the stickiness and plasticity of
the clay. Hillside ditches and diversions are difficult to
lay out, establish, and maintain. Crops respond well to
heavy applications of lime and fertilizers. Controlling ero-
sion is the major concern of management.
This soil has been used for such crops as plantains,
taniers, and yams. It is suited to pangolagrass, stargrass,
and Merker grass.
Proper stocking rates and deferred grazing, as well as
liming and fertilizing, are chief management needs.


This soil is suited to Honduras pine and eucalyptus
trees. Production of Honduras pine is moderate, about
1100 board feet per acre per year. The hazard of erosion
and limitations on the use of equipment are the major
concerns of management. Logging roads, skid trails, and
planting should be on the contour to help control erosion.
The use of logging equipment is restricted at times
because the soil is soft and slippery when wet. Brush
removal, careful hand planting, and fertilizing increase
the survival of planted seedlings.
This soil is limited for most urban uses because it is
steep and subject to landslides. If the soil is used as con-
struction sites, development should be on the contour.
Removal of vegetation should be held to a minimum, and
temporary plant cover established quickly in denuded
areas. Capability subclass VIe.
AmB-Almirante clay, 2 to 5 percent slopes. This is a
gently sloping, well drained soil on coastal plains and in
valleys between the limestone hills. Slopes are smooth
and are 800 to 1500 feet long. The areas range from 20 to
600 acres.
Typically the surface layer is dark yellowish brown, fri-
able clay about 7 inches thick. The subsoil is firm clay to
a depth of 60 inches. From 7 to 34 inches, it is strong
brown; from 34 to 46 inches, it is brownish yellow and
dark red; and from 46 to 60 inches, it is variegated
brownish yellow, dark red, and light gray.
Included with this soil in mapping are small areas of
the Vega Alta, Matanzas, and Bayamon soils. The surface
layer of the Vega Alta soils is dark yellowish brown clay
loam, and that of the Matanzas and Bayamon soils is dark
reddish brown clay. These soils make up 10 to 20 percent
of the areas of this mapping unit.
Permeability and the available water capacity are
moderate. Runoff is medium. This soil is medium in natu-
ral fertility and has a deep root zone. It is difficult to
work due to the stickiness and plasticity of the clay.
Crops respond well to heavy applications of lime and fer-
tilizers. Controlling erosion is a major concern of manage-
ment.
This soil has been used for sugarcane. It is best suited
to pangolagrass, stargrass, and Merker grass.
Proper stocking rates and deferred grazing, as well as
liming and fertilizing, are chief management needs.
This soil is moderately limited for most urban uses
because of its clayey nature. Capability subclass He.
AmC-Almirante clay, 5 to 12 percent slopes. This is
a sloping, well drained soil on coastal plains and in valleys
between the limestone hills. Slopes are smooth and are
400 to 1000 feet long. The areas range from 10 to 400
acres.
Typically the surface layer is dark yellowish brown, fri-
able clay about 7 inches thick. The subsoil is firm clay to
a depth of 60 inches. From 7 to 34 inches, it is strong
brown; from 34 to 46 inches, it is brownish yellow and
dark red; and from 46 to 60 inches, it is variegated
brownish yellow, dark red, and light gray.







SAN JUAN AREA, PUERTO RICO


Included with this soil in mapping are small areas of
Vega Alta, Matanzas, and Bayamon soils. The surface
layer of the Vega Alta soils is dark yellowish brown clay
loam; that of the Matanzas and Bayamon soils is dark
reddish brown clay. These soils make up 10 to 20 percent
of this mapping unit.
Permeability and the available water capacity are
moderate. Runoff is medium. This soil is medium in natu-
ral fertility and has a deep root zone. It is difficult to
work due to stickiness and plasticity of the clay. Crops
respond well to heavy applications of lime and fertilizers.
Controlling erosion is a major concern of management.
This soil has been used for sugarcane. It is suited to
pangolagrass, stargrass, and Meiker grass.
Proper stocking rates and deferred grazing, as well as
liming and fertilizing, are chief management needs.
This soil is moderately limited for most urban uses
because of its clayey nature. Capability subclass IIIe.
Ba-Bajura clay. This is a nearly level, poorly drained
soil on river flood plains. Slopes are smooth and are 500
to 2000 feet long. The areas range from 20 to 1000 acres.
Typically the surface layer is dark brown, firm clay
about 5 inches thick. The subsoil, about 7 inches thick, is
dark gray, firm clay mottled with yellowish brown, very
dark gray, and dark brown. The substratum, from a depth
of 12 inches to 31 inches, is gray and yellowish brown,
firm clay mottled with greenish gray. From 31 inches to
60 inches, the substratum is greenish gray, firm clay mot-
tled with brownish yellow and bluish gray.
Included with this soil in mapping are small areas of
the Coloso soils. The surface layer of the Coloso soils is
dark brown silty clay loam. These soils make up 10 to 20
percent of this mapping unit.
Permeability is slow and the available water capacity is
high. This soil is difficult to work due to stickiness and
plasticity of the clay and wetness. It is fertile and has a
deep root zone. When properly drained and managed, it is
suited to crops (fig. 1).
This soil has been used for sugarcane. It is suited to
pangolagrass, stargrass, and paragrass.
Proper stocking rates and deferred grazing, as well as
fertilizing, are chief management needs.
This soil is limited for most urban uses because of
drainage, flood hazard, and high shrink-swell potential.
Capability subclass IIIw.
BmB-Bayamon clay, 2 to 5 percent slopes. This is a
gently sloping, well drained soil on foot slopes and in
small valleys between the limestone hills. Slopes are 500
to 1000 feet long. The areas range from 10 to 300 acres.
Typically the surface layer is dark reddish brown, fria-
ble clay about 8 inches thick. The subsoil, to a depth of 66
inches is weak red and red, firm to friable clay.
Included with this soil in mapping are small areas of
Matanzas soils. The surface layer of the Matanzas soils is
dark reddish brown clay. These soils make up 10 to 20
percent of this mapping unit.
Permeability and the available water capacity are
moderate in this soil. Runoff is medium, and the hazard of


erosion is slight to moderate. This soil is difficult to work
because of the stickiness and plasticity of the clay. It is
medium in natural fertility and has a deep root zone.
Crops respond well to heavy applications of lime and fer-
tilizers. Controlling erosion and maintaining natural
fertility are the major concerns of management.
This soil has been used for sugarcane and pineapples. It
is suited to pangolagrass, stargrass, and Merker grass
(fig. 2).
Proper stocking rates and deferred grazing, as well as
liming and fertilizing, are chief management needs.
This soil has slight to moderate limitations for most
urban uses. If the soil is used for construction sites, tem-
porary plant cover should be established quickly in
denuded areas. Capability subclass IIe.
CaE-Caguabo clay loam, 20 to 40 percent slopes.
This is a steep, well drained soil on side slopes and tops
of strongly dissected uplands. Slopes are 500 to 1000 feet
long. The areas range from 20 to 800 acres.
Typically the surface layer is dark grayish brown, fria-
ble clay loam about 4 inches thick. The next layer is
brown, friable very gravelly clay loam about 6 inches
thick. The substratum, beginning at a depth of 10 inches,
is a mixture of weathered and partially weathered vol-
canic rocks. Consolidated rock is at a depth of 16 inches.
Included with this soil in mapping are small areas of
Mucara, Naranjito, and Consumo soils and a few rocky
hilltops. The surface layer of the Mucara soils is very
dark grayish brown clay; that of the Naranjito soils is
dark brown silty clay loam; and that of the Consumo soils
is reddish brown clay. These soils make up 10 to 20 per-
cent of this mapping unit.
Permeability is moderate in this soil, and the available
water capacity is low. Runoff is rapid, and erosion is a
hazard. Slippage is common in roadbanks, ditches, and
drainageways. This soil is difficult to work because it is
steep and shallow. Hillside ditches and diversions are dif-
ficult to lay out, establish, and maintain. This soil is fertile
but has a shallow root zone. Controlling erosion is the
major concern of management.
This soil has been used for tobacco and food crops such
as sweet potatoes, bananas, and coffee. It is best suited to
pangolagrass and stargrass.
Proper stocking rates and deferred grazing, as well as
liming and fertilizing, are chief management needs.
This soil is suited to Honduras pine, eucalyptus, and
mahogany trees. Production of Honduras pine is low,
about 800 board feet per acre per year. The hazard of
erosion and limitations on the use of equipment are the
major concerns of management. Logging roads, skid
trails, and planting should be on the contour to help con-
trol erosion. The use of logging equipment is restricted at
times because the soil is soft and slippery when wet.
Brush removal, careful hand planting, and fertilizing in-
crease the survival of planted seedlings.
This soil is limited for most urban uses because it is
steep, shallow, and subject to landslides. If the soil is used
as construction sites, development should be on the con-






SOIL SURVEY


tour. Removal of vegetation should be held to a minimum,
and temporary plant cover established quickly in denuded
areas. Capability subclass VIIs.
CaF-Caguabo clay loam, 40 to 60 percent slopes.
This is a very steep, well drained soil on side slopes and
mountaintops of strongly dissected uplands. Slopes are
400 to 800 feet long. The areas range from 20 to 2000
acres.
Typically the surface layer is dark grayish brown, fria-
ble clay loam about 4 inches thick. The next layer is about
5 inches thick; it is brown, friable very gravelly clay loam.
The substratum, beginning at a depth of 10 inches, is a
mixture of weathered and partially weathered volcanic
rocks. Consolidated rock is at a depth of 16 inches.
Included with this soil in mapping are small areas of
Mucara and Naranjito soils and a few spots that have
many boulders and stones on the surface. The surface
layer of the Mucara soils is very dark grayish brown clay,
and that of the Naranjito soils is dark brown silty clay
loam. These soils make up 10 to 20 percent of this
mapping unit.
Permeability is moderate, and the available water
capacity is low. Runoff is rapid, and erosion is a hazard.
Slippage is common in roadbanks, ditches, and
drainageways. This soil is difficult to work because it is
very steep and shallow. Hillside ditches and diversions
are difficult to lay out, establish, and maintain. The soil is
fertile but has a shallow root zone. Controlling erosion is
the major concern of management.
This soil has been used for tobacco and food crops such
as sweet potatoes, bananas, and coffee. It is best suited,
howeverto_pangolagrass and stargrass.
Proper stocking rates and deferred grazing, as well as
liming and fertilizing, are chief management needs.
This soil is suited to Honduras pine and eucalyptus
trees. Production of Honduras pine is low, about 700 to
800 board feet per acre per year. The hazard of erosion
and limitations on the use of equipment are the major
concerns of management. Logging roads, skid trails, and
planting should be on the contour to help control erosion.
The use of logging equipment is restricted at times
because the soil is soft and slippery when wet. Brush
removal, careful hand planting, and fertilizing increase
the survival of planted seedlings.
This soil is limited for most urban uses because it is
very steep, shallow, and subject to landslides. If the soil is
used as construction sites, development should be on the
contour. Removal of vegetation should be held to a
minimum, and temporary plant cover established quickly
in denuded areas. Capability subclass VIIs.
CbF-Caguabo-Rock outcrop complex, 40 to 60 per-
cent slopes. This complex consists of very steep, well
drained soils and Rock outcrop on side slopes and narrow
ridges. The areas range from 10 to 500 acres. The com-
plex is about 60 percent Caguabo clay loam and 40 per-
cent Rock outcrop and other minor soils. Caguabo and
Rock outcrop form such an intricate pattern that they
were not separated in mapping.


In a representative profile of Caguabo clay loam the
surface layer is about 3 inches thick. The next layer,
about 5 inches thick, is brown, friable very gravelly clay
loam. It is underlain by a mixture of weathered and par-
tially weathered volcanic rocks. Volcanic bedrock is at a
depth of 10 to 20 inches.
Included with this soil complex in mapping are spots of
deeper soils that formed between the rock outcrops. Also
included are some areas of severely eroded Caguabo soils
that have a thin surface layer of brown to dark grayish
brown clay loam. These soils are on ridgetops.
Permeability is moderate in the Caguabo soil, and the
available water capacity is low. The root zone is shallow.
Tilth is fair to poor. Surface runoff is very rapid. In un-
limed areas the soil is slightly acid.
The vegetation is shrubs, brush, and grass. This com-
plex is not suited to cultivated crops. The potential for
pasture is low. The Caguabo soil is suited to Honduras
pine and eucalyptus trees. Production of Honduras pine is
low, about 700 board feet per acre per year. The hazard
of erosion and the limitations on the use of equipment are
moderate. Logging roads, skid trails, and machine
plantings should be on the contour to help control erosion.
The use of equipment is restricted mainly by the very
steep slopes and the many rock outcrops.
This complex is poorly suited to most urban uses,
mainly because of the very steep slopes and shallow
depth to the volcanic rock, which is at a depth of 10 to 20
inches. Most of the areas are subject to slides. Erosion is
a severe hazard in areas not protected by vegetative
cover. In areas that are used as construction sites,
development should be on the contour. Removal of
vegetative cover should be held to a minimum, and plant
cover established quickly on denuded areas. Capability
subclass VIIIs.
Ce-Candelero loam. This is a gently sloping,
somewhat poorly drained soil on terraces, alluvial fans,
and foot slopes. Slopes are undulating and are 100 to 800
feet long. The areas range from 30 to 100 acres.
Typically the surface layer is dark grayish brown loam
about 6 inches thick. The subsoil from 6 inches to a depth
of 35 is mainly dark brown, dark gray, and very dark
gray, firm sandy clay loam mottled with yellowish brown,
greenish gray, and brownish yellow. From 35 inches to a
depth of 60 inches, the subsoil is brownish yellow and yel-
lowish brown, firm sandy clay mottled with gray,
greenish gray, and yellowish red.
Included with this soil in mapping are small areas of
Cayagua soils. The surface layer of the Cayagua soils is
dark grayish brown sandy loam. These soils make up 10
to 20 percent of this mapping unit.
Permeability is slow, and the available water capacity is
high. Runoff is medium. This soil is difficult to work due
to wetness and the stickiness and plasticity of the clay.
The root zone is deep. Natural fertility is medium. Crops
respond well to heavy applications of lime and fertilizers.
This soil has been used for sugarcane. It is suited to
pangolagrass, Merker grass, and paragrass.






SAN JUAN AREA, PUERTO RICO


This soil is limited for most urban uses because of wet-
ness, flood hazard, and its clayey nature. Removal of
vegetation should be held to a minimum, and temporary
plant cover established quickly in denuded areas. Capa-
bility subclass IIIe.
CIC-Catalina clay, 4 to 12 percent slopes. This is a
sloping, well drained soil on side slopes and hilltops of the
humid uplands. Slopes are 300 to 400 feet long. The areas
range from 10 to 150 acres.
Typically the surface layer is dark reddish brown, fria-
ble clay about 6 inches thick. The subsoil layers from 6
inches to a depth of 84 inches are reddish brown and dark
reddish brown firm clay. From 84 to 99 inches, the subsoil
is variegated dusky red, dark reddish brown, and strong
brown clay.
Included with this soil in mapping are small areas of
Humatas, Daguey, and Consumo soils. The surface layer
of the Humatas and Daguey soils is dark brown clay, and
that of the Consumo soils is reddish brown clay. These
soils make up 10 to 20 percent of this mapping unit.
Permeability and the available water capacity are
moderate. Runoff is medium, and erosion is a hazard.
Slippage is common in roadbanks, ditches, and
drainageways. This soil is difficult to work because of the
stickiness and plasticity of the clay. The root zone is deep.
Natural fertility is medium. Crops respond well to heavy
applications of lime and fertilizers. Controlling erosion is
the major concern of management.
This soil has been used for plantains, yams, taniers, and
coffee. It is suited to pangolagrass, stargrass, and Merker
grass.
Proper stocking rates and deferred grazing, as well as
liming and fertilizing, are chief management needs.
This soil is suited to Honduras pine, Honduras
mahogany, kadam, Eucalyptus robusta, and mahoe trees.
Production of Honduras pine is moderate, about 1100
board feet per acre per year. The hazard of erosion and
limitations on the use of equipment are the major con-
cerns of management. Logging roads, skid trails, and
planting should be on the contour to help control erosion.
The use of logging equipment is restricted at times
because the soil is soft and slippery when wet. Brush
removal, careful hand planting, and fertilizing increase
the survival of planted seedlings.
This soil is limited for most urban uses due to slope, its
clayey nature, and seepage. If the soil is used as construc-
tion sites, development should be on the contour. Removal
of vegetation should be held to a minimum, and tempora-
ry plant cover established quickly in denuded areas.
Capability subclass IIIe.
Cn-Catano loamy sand. This is a nearly level, exces-
sively drained soil on narrow strips of the coastal plain.
The areas range from 20 to 200 acres.
Typically the surface layer of this soil is very dark
grayish brown loamy sand about 7 inches thick. The next
layer is about 16 inches thick; it is dark brown, loose
sand. The substratum, beginning at a depth of 23 inches,
is dark grayish brown, loose sand.


Included with this soil in mapping are small areas of
Durados soils. The surface layer of the Durados soils is
very dark grayish brown sandy loam. These soils make up
10 to 20 percent of this mapping unit.
Permeability is rapid, and the available water capacity
is low. Runoff is very slow. This soil is easily worked. The
root zone is deep, but natural fertility is low. The soil is
very limited for farming.
This soil has been used for growing coconuts. It is
suited to pangolagrass and Merker grass.
Proper stocking rates and deferred grazing, as well as
fertilizing, are chief management needs.
This soil is suited to most urban uses. Capability sub-
class VIs.
Co-Cayagua sandy loam. This is a sloping, poorly
drained soil on alluvial fans. Slopes are 200 to 800 feet
long. The areas range from 50 to 300 acres.
Typically the surface layer is dark grayish brown, fria-
ble sandy loam about 8 inches thick. The subsoil is about
24 inches thick; it is yellowish brown and light olive gray,
firm clay mottled with red, yellowish red, strong brown,
and gray. The substratum, beginning at a depth of 32
inches, is yellowish brown, white, and gray, friable, sandy
clay loam saprolite.
Included with this soil in mapping are some areas of
Candelero soils. The surface layer of the Candelero soils
is dark grayish brown loam. These soils make up about 10
to 20 percent of this mapping unit.
Permeability is slow, and the available water capacity is
high. Runoff is slow. This soil is difficult to work because
of wetness. The root zone is deep. Natural fertility is
medium. Crops respond well to heavy applications of lime
and fertilizers.
This soil has been used for sugarcane. It is suited to
pangolagrass, paragrass, and Merker grass.
Proper stocking rates and deferred grazing, as well as
liming and fertilizing, are chief management needs.
This soil is limited for most urban uses because of wet-
ness, seepage, and slope. If the soil is used as construction
sites, development should be held to a minimum, and tem-
porary plant cover established quickly in denuded areas.
Capability subclass IIIe.
CrD2-Colinas clay loam, 12 to 20 percent slopes,
eroded. This is a moderately steep, well drained soil on
ridgetops and side slopes of low rolling hills. Slopes are
convex and are 200 to 500 feet long. The areas range
from 10 to 300 acres. This soil has lost much of its
original surface layer through erosion.
Typically the surface layer is dark brown, friable clay
loam about 11 inches thick. The subsoil is about 15 inches
thick; it is brownish yellow, friable clay loam. The sub-
stratum, beginning at a depth of 26 inches, is pale yellow,
very friable, soft limestone that crushes to silty clay loam.
From 48 to 52 inches, the substratum is yellow and white,
soft limestone.
Included with this soil in mapping are small areas of
Soller and Tanama soils. The surface layer of the Soller
soils is very dark grayish brown clay loam; that of the







SOIL SURVEY


Tanama soils is dark reddish brown clay. These soils
make up 10 to 20 percent of this mapping unit.
Permeability is moderate, and the available water
capacity is low. Runoff is rapid, and erosion is a hazard.
Slippage is common in roadbanks, ditches, and
drainageways. This soil is difficult to work because it is
moderately steep and because of the stickiness and
plasticity of the surface layer. The root zone is moderate-
ly deep. Natural fertility is low. Controlling erosion is the
major concern of management.
This soil has been used for sugarcane. It is suited to
pangolagrass, stargrass, and Merker grass.
Proper stocking rates and deferred grazing, as well as
fertilizing, are chief management needs.
This soil is suited to Honduras pine, Honduras
mahogany, mahoe, and teak trees. Production of Hondu-
ras mahogany is very low, about 450 board feet per acre
per year. The hazard of erosion and limitations on the use
of equipment are the major concerns of management.
Logging roads, skid trails, and planting should be on the
contour to help control erosion. The use of logging equip-
ment is restricted at times because the soil is soft and
slippery when wet. Brush removal, careful hand planting,
and fertilizing increase the survival of planted seedlings.
This soil is limited for most urban uses because it is
moderately steep. If the soil is used as construction sites,
development should be on the contour. Removal of
vegetation should be held to a minimum, and temporary
plant cover established quickly in denuded areas. Capa-
bility subclass IVe.
CrE2-Colinas clay loam, 20 to 40 percent slopes,
eroded. This is a steep, well drained soil on ridgetops and
side slopes of low hills. Slopes are convex and are 100 to
300 feet long. The areas range from 20 to 400 acres. This
soil has lost much of its original surface layer through
erosion.
Typically the surface layer is dark brown, friable clay
loam about 11 inches thick. The subsoil is about 15 inches
thick; it is brownish yellow, friable clay loam. The sub-
stratum, beginning at a depth of 26 inches, is pale yellow,
very friable, soft limestone that crushes to silty clay loam.
From 48 to 52 inches, the substratum is yellow and white
soft limestone.
Included with this soil in mapping are some areas of
Soller and Tanama soils. The surface layer of the Soller
soils is very dark grayish brown clay loam, and that of
the Tanama soils is dark reddish brown clay. These soils
make up 10 to 20 percent of this mapping unit.
Permeability is moderate, and the available water
capacity is low. Runoff is rapid, and erosion is a hazard.
This soil is difficult to work because it is steep and
because of the stickiness and plasticity of the surface
layer. Hillside ditches and diversions are difficult to lay
out, establish, and maintain. The root zone is moderately
deep. Natural fertility is low. Controlling erosion is the
major concern of management.
This soil has been used for sugarcane. It is suited to
pangolagrass, stargrass, and Merker grass.


Proper stocking rates and deferred grazing are chief
management needs.
This soil is suited to Honduras mahogany. Production of
Honduras mahogany is very low, about 350 board feet per
acre per year. The hazard of erosion and limitations on
the use of equipment are the major concerns of manage-
ment. Logging roads, skid trails, and planting should be
on.the contour to help control erosion. The use of logging
equipment is restricted at times because the soil is soft
and slippery when wet. Brush removal, careful hand
planting, and fertilizing increase the survival of planted
seedlings.
This soil is limited for most urban uses because it is
steep and subject to landslides. If the soil is used as con-
struction sites, development should be on the contour.
Removal of vegetation should be held to a minimum, and
temporary plant cover established quickly in denuded
areas. Capability subclass VIe.
CrF2-Colinas clay loam, 40 to 60 percent slopes,
eroded. This is a very steep, well drained soil on
ridgetops and side slopes of hills. Slopes are convex and
are 100 to 400 feet long. The areas range from 50 to 300
acres. This soil has lost much of its original surface layer
through erosion. A few shallow to deep gullies have
formed.
Typically the surface layer is dark brown, friable clay
loam about 11 inches thick. The subsoil is about 15 inches
thick; it is brownish yellow, friable clay loam. The sub-
stratum, beginning at a depth of 26 inches, is pale yellow,
very friable, soft limestone that crushes to silty clay loam.
From 48 to 52 inches, the substratum is yellow and white
soft limestone.
Included with this soil in mapping are some areas of
Soller and Tanama soils. The surface layer of the Soller
soils is very dark grayish brown clay loam, and that of
the Tanama soils is dark reddish brown clay. These soils
make up 10 to 20 percent of this mapping unit.
Permeability is moderate, and the available water
capacity is low. Runoff is rapid, and erosion is a hazard.
This soil is difficult to work because it is very steep and
because of the stickiness and plasticity of the surface
layer. Hillside ditches and diversions are difficult to lay
out, establish, and maintain. The root zone is moderately
deep. Natural fertility is low. Controlling erosion is the
major concern of management.
This soil has been used for sugarcane. It is suited to
pangolagrass.
Proper stocking rates and deferred grazing are chief
management needs.
This soil is limited for most urban uses because it is
very steep and is subject to landslides. If the soil is used
as construction sites, development should be on the con-
tour. Removal of vegetation should be held to a minimum,
and temporary plant cover established quickly in denuded
areas. Capability subclass VIIe.
Cs-Coloso silty clay loam. This is a nearly level,
somewhat poorly drained soil on river flood plains. Slopes
are smooth and 200 to 1000 feet long. The areas range
from 100 to 600 acres.







SAN JUAN AREA, PUERTO RICO


Typically the surface layer is dark brown, friable silty
clay loam about 7 inches thick. The underlying material
from 7 to 16 inches is dark brown and dark yellowish
brown, friable silty clay loam, from 16 to 32 inches is dark
grayish brown and light gray silty clay loam mottled with
dark yellowish brown, and from 32 to 70 inches is
greenish gray silty clay mottled with yellowish red and
yellowish brown.
Included with this soil in mapping are small areas of
Toa and Bajura soils. The surface layer of the Toa soils is
dark brown silty clay loam, and that of the Bajura soils is
dark brown clay. These soils make up 10 to 20 percent of
this mapping unit.
Permeability is slow, and the available water capacity is
high. Runoff is slow. This soil is difficult to work because
of the wetness and the stickiness and plasticity of the
surface layer. The root zone is deep. This soil is fertile.
Crops respond well to heavy applications of fertilizers.
This soil has been used for sugarcane (fig. 3). It is
suited to pangolagrass, stargrass, and Merker grass.
Proper stocking rates and deferred grazing, as well as
fertilizing, are chief management needs.
This soil is limited for most urban uses because it is
somewhat poorly drained, too clayey, and subject to over-
flow. Capability subclass IIw.
CuE-Consumo clay, 20 to 40 percent slopes. This is
a steep, well drained soil on side slopes of maturely dis-
sected humid uplands. Slopes are irregular and are 200 to
1000 feet long. The areas range from 100 to 800 acres.
This soil has lost much of its original surface layer
through erosion. A few shallow to deep gullies have
formed.
Typically the surface layer is reddish brown friable clay
about 10 inches thick. The subsoil is about 10 inches thick;
it is yellowish red, friable clay. The substratum, beginning
at a depth of 20 inches, is red, brownish yellow, and yel-
lowish red, very friable, silty clay loam saprolite.
Included with this soil in mapping are spots of Hu-
matas, Naranjito, and Mucara soils. The surface layer of
the Humatas soils is dark brown clay, and that of the
Naranjito soils is brown to dark brown silty clay loam.
The surface layer of the Mucara soils is very dark grayish
brown clay. These included soils make up about 10 to 20
percent of this mapping unit.
Permeability and the available water capacity are
moderate. Runoff is rapid, and erosion is a hazard. Slip-
page is common in roadbanks, ditches, and drainageways.
This soil is difficult to work because it is steep and
because of the stickiness and plasticity of the clay. Hill-
side ditches and diversions are difficult to lay out,
establish, and maintain. The root zone is deep. Natural
fertility is medium. Crops respond well to heavy applica-
tions of lime and fertilizers. Controlling erosion is the
major concern of management. This soil has been used for
crops such as coffee. It is suited to pangolagrass and to
molasses grass.
Proper stocking rates and deferred grazing, as well as
liming and fertilizing, are chief management needs.


This soil is suited to Honduras pine and Eucalyptus
robusta trees. Production of Honduras pine is moderate,
about 1100 board feet per acre per year. The hazard of
erosion and limitations on the use of equipment are the
major concerns of management. Logging roads, skid
trails, and planting should be on the contour to help con-
trol erosion. The use of logging equipment is restricted at
times because the soil is soft and slippery when wet.
Brush removal, careful hand planting, and fertilizing in-
crease the survival of planted seedlings.
This soil is limited for most urban uses because it is
steep and subject to landslides. If the soil is used as con-
struction sites, development should be on the contour.
Removal of vegetation should be held to a minimum, and
temporary plant cover established quickly in denuded
areas. Capability subclass VIe.
CuF-Consumo clay, 40 to 60 percent slopes. This is a
very steep, well drained soil on side slopes of maturely
dissected humid uplands. Slopes are irregular and are 200
to 800 feet long. The areas range from. 100 to 1000 acres.
This soil has lost much of its original surface layer
through erosion. A few shallow to deep gullies have
formed.
Typically the surface layer is reddish brown friable clay
about 10 inches thick. The subsoil is about 10 inches thick;
it is yellowish red, friable clay. The substratum, beginning
at a depth of 20 inches, is red, brownish yellow, and yel-
lowish red, very friable, silty clay loam saprolite.
Included with this soil in mapping are spots of Hu-
matas, Naranjito, and Mucara soils. The surface layer of
the Humatas soils is dark brown clay, and that of the
Naranjito soils is brown to dark brown silty clay loam.
The surface layer of the Mucara soils is very dark grayish
brown clay. These soils make up 10 to 20 percent of this
mapping unit.
Permeability and the available water capacity are
moderate. Runoff is very rapid, and erosion is a hazard.
Slippage is common in roadbanks, ditches, and
drainageways. This soil is difficult to work because it is
very steep and because of the stickiness and plasticity of
the clay. Hillside ditches and diversions are difficult to
lay out, establish, and maintain. The root zone is deep.
Natural fertility is medium. Crops respond well to heavy
applications of lime and fertilizers. Controlling erosion is
the major concern of management.
This soil has been used for crops such as coffee. It is
suited to pangolagrass and to molasses grass.
Proper stocking rates and deferred grazing, as well as
liming and fertilizing, are chief management needs.
This soil is suited to Honduras pine and Eucalyptus
robusta trees. Production of Honduras pine is moderate,
about 1000 board feet per acre per year. The hazard of
erosion and limitations on the use of equipment are the
major concerns of management. Logging roads, skid
trails, and planting should be on the contour to help con-
trol erosion. The use of logging equipment is restricted at
times because the soil is soft and slippery when wet.
Brush removal, careful hand planting, and fertilizing in-
crease the survival of planted seedlings.






SOIL SURVEY


This soil is limited for most urban uses because it is
very steep and is subject to landslides. If the soil is used
as construction sites, development should be on the con-
tour. Removal of vegetation should be held to a minimum,
and temporary plant cover established quickly in denuded
areas. Capability subclass VIIe.
CzC-Corozal clay, 5 to 12 percent slopes. This is a
sloping, somewhat poorly drained soil on interfluves of
strongly dissected low volcanic hills. Slopes are 200 to 400
feet long. The areas range from 20 to 100 acres.
Typically the surface layer is dark reddish brown, firm
clay about 7 inches thick. The subsoil is about 33 inches
thick; it is mostly red, firm clay. The substratum,
beginning at a depth of 40 inches, is yellowish red, light
gray, and strong brown, friable, clay loam saprolite.
Included with this soil in mapping are small areas of
Consumo, Daguey, and Humatas soils. The surface layer
of the Consumo soils is reddish brown clay, and that of
the Daguey and Humatas soils is dark brown clay. These
soils make up 10 to 20 percent of the area of this mapping
unit.
Permeability is slow, and the available water capacity is
high. Runoff is medium, and erosion is a hazard. This soil
is difficult to work because of the stickiness and plasticity
of the clay. The root zone is deep. Natural fertility is
medium. Crops respond well to heavy applications of lime
and fertilizers. Controlling erosion is the major concern of
management.
This soil has been used for crops such as taniers and
plantains. It is suited to pangolagrass, Merker grass, and
improved bermudagrass.
Proper stocking rates and deferred grazing, as well as
liming and fertilizing, are chief management needs.
This soil is limited for most urban uses due to its
clayey nature and wetness. If the soil is used as construc-
tion sites, development should be on the contour. Removal
of vegetation should be held to a minimum, and tempora-
ry plant cover established quickly in denuded areas.
Capability subclass IIIe.
DaC-Daguey clay, 2 to 12 percent slopes. This is a
gently sloping to sloping soil on stable side slopes,
ridgetops, and foot slopes of the humid volcanic uplands.
Slopes are 200 to 800 feet long. The areas range from 20
to 200 acres.
Typically the surface layer is dark brown firm clay
about 10 inches thick. The subsoil is about 62 inches thick;
it is yellowish red and red, firm clay. The substratum,
beginning at a depth of 72 inches, is yellowish red, strong
brown, and reddish yellow, friable, silty clay loam
saprolite.
Included with this soil in mapping are small areas of
Humatas and Catalina soils. The surface layer of the Hu-
matas soils is dark brown clay; that of the Catalina soils
is dark reddish brown clay. These soils make up 10 to 20
percent of this mapping unit.
Permeability and the available water capacity are
moderate in this soil. Runoff is medium, and erosion is a
hazard. This soil is difficult to work because of the sticki-


ness and plasticity of the clay. The root zone is deep.
Natural fertility is medium. Crops respond well to heavy
applications of lime and fertilizers. Controlling erosion is
the major concern of management.
This soil has been used for crops such as plantains,
yams, taniers, and coffee. It is suited to pangolagrass and
Merker grass.
Proper stocking rates and deferred grazing, as well as
liming and fertilizing, are chief management needs.
This soil is suited to Honduras pine, Honduras
mahogany, kadam, and mahoe trees. Production of Hondu-
ras pine is moderate about 1300 board feet per acre per
year. Logging roads, skid trails, and planting should be on
the contour to help control erosion. The use of logging
equipment is restricted at times because the soil is soft
and slippery when wet. Brush removal, careful hand
planting, and fertilizing increase the survival of planted
seedlings.
Slope is a moderate limitation for most urban uses. If
the soil is used as construction sites, development should
be on the contour. Removal of vegetation should be held
to a minimum, and temporary plant cover established
quickly in denuded areas. Capability subclass IIIe.
DaD-Daguey clay, 12 to 20 percent slopes. This is a
moderately steep, well drained soil on stable side slopes,
ridgetops, and foot slopes of the humid volcanic uplands.
Slopes are 100 to 500 feet long. The areas range from 20
to 200 acres.
Typically the surface layer is brown, firm clay about 10
inches thick. The subsoil is about 62 inches thick; it is yel-
lowish red and red, firm clay. The substratum, beginning
at a depth of 72 inches, is yellowish red, friable silty clay
loam saprolite mottled with strong brown and reddish
yellow.
Included with this soil in mapping are small areas of
Humatas and Catalina soils. The surface layer of the Hu-
matas soils is dark brown clay. That of the Catalina soils
is dark reddish brown clay. These soils make up 10 to 20
percent of this mapping unit.
Permeability and the available water capacity are
moderate. Runoff is rapid, and erosion is a hazard. This
soil is difficult to work because it is moderately steep (fig.
4) and because of the stickiness and plasticity of the clay.
The root zone is deep. Natural fertility is medium. Crops
respond well to heavy applications of lime and fertilizers.
Controlling erosion is the major concern of management.
This soil has been used for plantains, yams, taniers, and
coffee. It is suited to pangolagrass and Merker grass.
Proper stocking rates and deferred grazing, as well as
liming and fertilizing, are chief management needs.
This soil is suited to Honduras pine and Eucalyptus
robusta. Production of Honduras pine is moderate, about
1300 board feet per acre per year. The hazard of erosion
and limitations on the use of equipment are major con-
cerns of management. Logging roads, skid trails, and
planting should be on the contour to help control erosion.
The use of logging equipment is restricted at times
because the soil is soft and slippery when wet. Brush







SAN JUAN AREA, PUERTO RICO


removal, careful hand planting, and fertilizing increase
the survival of planted seedlings.
This soil is limited for most urban uses because it is
steep and subject to landslides. If the soil is used as con-
struction sites, development should be on the contour.
Removal of vegetation should be held to a minimum, and
temporary plant cover established quickly in denuded
areas. Capability subclass IIIe.
DeF-Descalabrado clay loam, 40 to 60 percent
slopes. This is a very steep, well drained soil on side
slopes and tops of strongly dissected uplands. Slopes are
200 to 1000 feet long. The areas range from 100 to 1000
acres.
Typically the surface layer is very dark grayish brown,
friable clay loam about 5 inches thick. The subsoil is about
6 inches thick; it is dark brown, firm gravelly clay. The
substratum, beginning at a depth of 11 inches, is dark yel-
lowish brown and olive, friable gravelly sandy clay loam.
Hard rock is at a depth of 17 inches.
Included with this soil in mapping are a few spots of
Descalabrado-Rock outcrop complex and Guayama soils.
The surface layer of the Guayama soils is dark reddish
brown clay loam. These soils make up 10 to 20 percent of
this mapping unit.
Permeability is moderate, and the available water
capacity is low. Runoff is rapid, and erosion is a hazard.
This soil is difficult to work because it is steep. Hillside
ditches and diversions are difficult to lay out, establish,
and maintain. This soil is fertile, but has a shallow root
zone. It is not suited to cultivated crops because it is in
areas of low rainfall. The vegetation is brush and brushy
pasture.
This soil is suited to Honduras pine. Production is very
low, less than 800 board feet per acre per year. The
hazard of erosion and limitations on the use of equipment
are the major concerns of management. Logging roads,
skid trails, and planting should be on the contour to help
control erosion. Brush removal, careful hand planting, and
fertilizing increase the survival of planted seedlings.
This soil is limited for most urban uses because it is
very steep and subject to landslides. If the soil is used as
construction sites, development should be on the contour.
Removal of vegetation should be held to a minimum, and
temporary plant cover established quickly in denuded
areas. Capability subclass VIIs.
DgF-Descalabrado-Rock outcrop complex, 40 to 60
percent slopes. This complex consists of very steep, well
drained soils and Rock outcrop on strongly dissected
slopes. The areas range from 100 to 500 acres. The com-
plex is 70 percent Descalabrado clay loam and 30 percent
Rock outcrop and other minor soils.
In a representative profile of Descalabrado clay loam
the surface layer is very dark grayish brown clay loam
about 5 inches thick. The subsoil, about 6 inches thick, is
dark brown, firm gravelly sandy clay loam. The sub-
stratum, beginning at a depth of 11 inches, is dark yel-
lowish brown and olive, friable gravelly sandy clay loam.
Hard consolidated volcanic rock is at a depth of 17 inches.


Rock outcrop consists of exposed bedrock occurring in
such an intricate pattern with the Descalabrado soils that
it was impractical to separate them in mapping.
Included with this soil complex in mapping are spots of
Guayama and other miscellaneous soils with varying soil
properties.
Permeability is moderate in the Descalabrado soil, and
the available water capacity is low. Runoff is rapid. Natu-
ral fertility is high, and organic matter content is
moderate. Reaction is neutral. The root zone is shallow.
The vegetation is brush and brushy pasture. This com-
plex is not suited to cultivated crops. The best potential is
for wildlife habitat. Potential for production of Honduras
pine is very low, less than 800 board feet per acre per
year.
The hazard of erosion and the limitations on the use of
equipment are major concerns of management. Plant com-
petition is severe for Honduras pine.
This complex has severe limitations for most urban
uses because it is very steep. Capability subclass VIIs.
Dm-Dique loam. This is a nearly level, well drained
soil on river flood plains. Slopes are smooth and are 50 to
300 feet long. The areas range from 5 to 100 acres.
Typically the surface layer is dark brown, friable loam
about 6 inches thick. The subsoil is about 30 inches thick;
it is dark brown and dark yellowish brown, friable loam.
The substratum, beginning at a depth of 36 inches, is dark
yellowish brown, friable loam.
Included with this soil in mapping are small areas of
Toa soils. The surface layer of the Toa soils is dark brown
silty clay loam.
Permeability and the available water capacity are
moderate. Runoff is medium. This soil is easily worked.
The root zone is deep. Natural fertility is high. Crops
"respond well to fertilizer.
This soil has been used for sugarcane (fig. 5). It is
suited to pangolagrass, Merker grass, and improved
bermudagrass.
Proper stocking rates and deferred grazing, as well as
fertilizing, are chief management needs.
This soil is limited for most urban uses because of the
flood hazard. Capability class I.
Dr-Durados sandy loam. This is a nearly level, exces-
sively drained soil on coastal plains. Slopes are smooth
and are 50 to 100 feet long. The areas range from 20 to
100 acres.
Typically the surface layer is very dark grayish brown,
very friable sandy loam about 14 inches thick. The layer
from 14 to 23 inches is very dark grayish brown, loose
loamy sand. Below a depth of 23 inches is loose sand of
mixed colors and some thick layers of cemented sand.
Included with this soil in mapping are some areas of
Catano soils and coastal beaches. The surface layer of
Catano soils is very dark grayish brown loamy sand.
Catano soils and coastal beaches make up 10 to 20 percent
of this mapping unit.
Permeability is rapid, and the available water capacity
is low. Runoff is very slow. This soil is easily worked. The
root zone is deep. Natural fertility is low.







SOIL SURVEY


This soil has been used for coconuts. It is suited to pan-
golagrass, improved bermudagrass, and Merker grass.
This soil is limited for most urban uses because of the
flood hazard. Capability subclass VIs.
Es-Estacion silty clay loam. This is a nearly level,
well drained soil on river flood plains. Slopes are smooth
and are 100 to 400 feet long. The areas range from 10 to
200 acres.
Typically the surface layer is dark brown, friable silty
clay loam about 8 inches thick. The layer from 8 to 20
inches is very dark grayish brown, friable gravelly clay
loam. Below 20 inches is dark brown, loose gravelly sand.
Included with this soil in mapping are small areas of
Reilly, Dique, and Toa soils. The surface layer of the
Reilly soils is dark brown sandy loam, that of the Toa
soils is dark brown silty clay loam, and that of the Dique
soils is dark brown loam. These soils make up 10 to 20
percent of this mapping unit.
Permeability is moderate, and the available water
capacity is low. Runoff is slow. This soil is easily worked.
The root zone is moderately deep. Natural fertility is
high. Crops respond well to fertilizers.
This soil has been used for sugarcane. It is suited to
pangolagrass, Merker grass, and improved bermudagrass.
Proper stocking rates and deferred grazing, as well as
liming and fertilizing, are chief management needs.
This soil is limited for most urban uses because of the
flood hazard. Capability subclass IIIs.
GuF-Guayama clay loam, 20 to 60 percent slopes.
This is a steep to very steep, well drained soil on side
slopes and narrow ridgetops of dissected volcanic uplands.
Slopes are irregular and are 100 to 800 feet long. The
areas range from 50 to 300 acres.
Typically the surface layer is dark reddish brown, fria-
ble clay loam about 4 inches thick. The subsoil is about 8
inches thick; it is red, friable gravelly clay. The sub-
stratum, beginning at a depth of 12 inches, is red, friable
gravelly silty clay loam. Consolidated volcanic rock is at a
depth of 20 inches.
Included with this soil in mapping are small areas of
Rock outcrop and Descalabrado soils. The surface layer of
the Descalabrado soils is very dark grayish brown clay
loam. Rock outcrop consists of exposed bedrock and thin
patches of soil over rock. These soils make up 10 to 20
percent of this mapping unit.
Permeability is moderate, and the available water
capacity is low. Runoff is rapid, and erosion is a hazard.
This soil is difficult to work because it is steep. Hillside
ditches and diversions are difficult to lay out, establish,
and maintain. The root zone is shallow. Natural fertility is
low. Controlling erosion is the major concern of manage-
ment.
This soil has been used for pasture. It is suited to
guineagrass.
Proper stocking rates and deferred grazing, as well as
liming and fertilizing, are chief management needs.
This soil is suited to Honduras pine. Production is very
low, less than 800 board feet per acre per year. The


hazard of erosion and limitations on the use of equipment
are the major concerns of management. Logging roads,
skid trails, and planting should be on the contour to help
control erosion. Brush removal, careful hand planting, and
fertilizing increase the survival of planted seedlings.
This soil is limited for most urban uses because it is
steep to very steep and subject to landslides. If the soil is
used as construction sites, development should be on the
contour. Removal of vegetation should be held to a
minimum, and temporary plant cover established quickly
in denuded areas. Capability subclass VIIs.
Hm-Humacao loam. This is a nearly level, well
drained soil on terraces. Slopes are smooth and are about
50 to 200 feet long. The areas range from 10 to 100 acres.
Typically the surface layer is dark brown, friable loam
about 8 inches thick. The subsoil is about 7 inches thick; it
is dark yellowish brown, friable sandy clay loam. The sub-
stratum, beginning at a depth of 15 inches, is brown and
strong brown, friable clay loam and reddish yellow, very
friable sandy clay loam.
Included with this soil in mapping are some spots of
Candelero soils. The surface layer of the Candelero soils
is dark grayish brown loam. These soils make up 10 to 20
percent of this mapping unit.
Permeability and the available water capacity are
moderate. Runoff is medium. This soil is easily worked.
The root zone is deep. Natural fertility is medium. Crops
respond well to heavy applications of lime and fertilizers.
This soil has been used for crops such as sugarcane,
taniers, and plantains. It is suited to pangolagrass and
Merker grass.
Proper stocking rates and deferred grazing, as well as
liming and fertilizing, are chief management needs.
This soil is suited to most urban uses. Capability sub-
class IIe.
HtE- Humatas clay, 20 to 40 percent slopes. This is
a steep, well drained soil on side slopes and ridgetops of
strongly dissected humid uplands (fig. 6). Slopes are con-
vex and are 200 to 1000 feet long. The areas range from
10 to 300 acres.
Typically the surface layer is dark brown, friable clay
about 5 inches thick. The subsoil is about 29 inches thick;
it is red friable clay and yellowish red, friable silty clay.
The substratum, beginning at a depth of 34 inches, is red,
dark red, yellowish red, strong brown, and olive yellow,
friable silty clay saprolite.
Included with this soil in mapping are some narrow
foot slopes and soils that have less than 20 percent slopes.
Also included are spots of Consumo soils and, on a few
hilltops, small areas of Daguey soils. The surface layer of
the Consumo soils is reddish brown clay, and that of the
Daguey soils is dark brown clay. These soils make up 10
to 20 percent of this mapping unit.
Permeability and the available water capacity are
moderate. Runoff is rapid, and erosion is a hazard. Slip-
page is common in roadbanks, ditches, and drainageways.
This soil is difficult to work because it is steep and
because of the stickiness and plasticity of the clay. Hill-







SAN JUAN AREA, PUERTO RICO


side ditches and diversions are difficult to lay out,
establish, and maintain. The root zone is deep. Natural
fertility is medium. Crops respond well to heavy applica-
tions of lime and fertilizers. Controlling erosion is the
major concern of management.
This soil has been used for crops such as taniers, plan-
tains, yams, tobacco, and coffee. It is suited to pan-
golagrass and Merker grass.
Proper stocking rates and deferred grazing, as well as
liming and fertilizing, are chief management needs.
This soil is suited to Honduras pine and eucalyptus
trees. Production of Honduras pine is moderate, about
1100 board feet per acre per year. The hazard of erosion
and limitations on the use of equipment are the major
concerns of management. Logging, roads, skid trails, and
planting should be on the contour to help control erosion.
The use of logging equipment is restricted at times
because the soil is soft and slippery when wet. Brush
removal, careful hand planting, and fertilizing increase
the survival of planted seedlings.
This soil is limited for most urban uses because it is
steep and subject to landslides. If the soil is used as con-
struction sites, development should be on the contour.
Removal of vegetation should be held to a minimum, and
temporary plant cover established quickly in denuded
areas. Capability subclass IVe.
HtF-Humatas clay, 40 to 60 percent slopes. This is a
very steep, well drained soil on side slopes and ridgetops
of strongly dissected humid uplands. Slopes are convex
and are 200 to 1000 feet long. The areas range from 10 to
500 acres.
Typically the surface layer is dark brown, friable clay
about 5 inches thick. The subsoil is about 29 inches thick;
it is red friable clay and yellowish red, friable silty clay.
The substratum, beginning at a depth of 34 inches, is red,
dark red, yellowish red, strong brown, and olive yellow,
friable silty clay saprolite.
Included with this soil in mapping are some spots of
Consumo soils and, on a few hilltops, small areas of
Daguey soils. The surface layer of the Consumo soils is
reddish brown clay, and that of the Daguey soils is dark
brown clay. These soils make up 10 to 20 percent of this
mapping unit.
Permeability and the available water capacity are
moderate. Runoff is rapid, and erosion is a hazard. Slip-
page is common in roadbanks, ditches, and drainageways.
This soil is difficult to work because it is very steep and
because of the stickiness and plasticity of the clay. Hill-
side ditches and diversions are difficult to lay out,
establish, and maintain. The root zone is deep. Natural
fertility is medium. Crops respond well to heavy applica-
tions of lime and fertilizers. Controlling erosion is the
major concern of management.
This soil has been used for crops such as taniers, plan-
tains, yams, tobacco, and coffee. It is suited to pan-
golagrass and Merker grass.
Proper stocking rates and deferred grazing, as well as
liming and fertilizing, are chief management needs.


This soil is suited to Honduras pine and eucalyptus
trees. Production of Honduras pine is moderate, about
1000 board feet per acre per year. The hazard of erosion
and limitations on the use of equipment are the major
concerns of management. Logging roads, skid trails, and
planting should be on the contour to help control erosion.
The use of logging equipment is restricted at times
because the soil is soft and slippery when wet. Brush
removal, careful hand planting, and fertilizing increase
the survival of planted seedlings.
This soil is limited for most urban uses because it is
very steep and subject to landslides. If the soil is used as
construction sites, development should be on the contour.
Removal of vegetation should be held to a minimum, and
temporary plant cover established quickly in denuded
areas. Capability subclass VIe.
HuF-Humatas-Rock outcrop complex, 20 to 60 per-
cent slopes. This complex consists of steep and very
steep, well drained Humatas soils and Rock outcrop on
side slopes and narrow ridgetops of the volcanic humid
uplands. Slopes are mostly convex and 200 to 800 feet
long. The areas have rough surfaces that are covered
with rock outcrops. The areas range from 20 to 100 acres.
Humatas clay occurs in areas between the outcrops of
rock in such an intricate pattern that it was not practical
to separate them in mapping. The dark brown clay sur-
face layer of the Humatas soils contrasts markedly, with
the outcrops and other included soils.
This complex is about 45 percent Humatas clay, 40 per-
cent Rock outcrop, and 15 percent other soils.
Typically the surface layer of the Humatas soil in this
complex is dark brown, friable clay about 5 inches thick.
The subsoil is about 29 inches thick; it is red, friable clay
and yellowish red, friable silty clay. The substratum,
beginning at a depth of 34 inches, is red, dark red, yel-
lowish red, strong brown, and olive yellow, friable silty
clay saprolite. The other component of this complex con-
sists of boulders ranging from 5 to 15 feet in diameter
and outcrops of rock.
Included with this complex in mapping, making up
about 15 percent of the areas, are other soils with varia-
ble properties.
Most areas of this complex are in brush and brushy
pasture. Runoff is rapid, and erosion is a hazard. Because
of steep to very steep slopes and the large number of
boulders and outcrops of rock on the surface, the poten-
tial for farming is very poor. This soil has very poor
potential for most urban uses because it is steep to very
steep. Potential is best for growing trees and developing
habitat for woodland wildlife. The hazard of erosion is
severe. Removal of vegetation should be held to a
minimum.
This complex is suitable for Honduras pine and euca-
lyptus trees. Productivity is moderate, the hazard of ero-
sion is high, and there are limitations to the use of equip-
ment. Management practices such as removal of undesira-
ble brush, trees, and grasses and erosion control measures
are difficult to apply.







Cfr OTTLSD'tT'V


18 1

This complex is limited for most urban uses because
the soils are steep to very steep and rocky. Capability
subclass VIIs.
Hy-Hydraquents, saline. These are nearly level, very
poorly drained soils in lagoonlike places and in depres-
sions adjacent to the coast. The areas range from 20 to
200 acres. These soils are covered with brackish water
most of the year and are frequently flooded.
Color and texture vary throughout the profile of the
soil. The underlying material ranges from sand to clay.
Permeability is very slow, and the available water
capacity is very high. Runoff is very slow. Reclamation is
very difficult and costly.
These soils support mangrove trees and other
halophytic vegetation most of the time. They have severe
limitations for most urban uses because they are very
poorly drained and are subject to frequent overflow.
Capability subclass VIIIw.
JaE2-Jagueyes loam, 20 to 40 percent slopes,
eroded. This is a steep, well drained soil on side slopes
and narrow ridgetops. Slopes are 100 to 500 feet long.
The areas range from 10 to 100 acres.
Typically the surface layer is dark yellowish brown, fri-
able loam about 5 inches thick. The subsoil is' about 49
inches thick; it is yellowish red and red, friable clay loam
to a depth of 41 inches. From 41 to 54 inches, it is red,
friable sandy clay loam mottled with brownish yellow and
light gray. The substratum, beginning at a depth of 54
inches, is yellowish red, friable, sandy clay loam saprolite.
Included with this soil in mapping are small areas of
Lirios and Limones soils. Also included on some hilltops
are areas of Jagueyes soils where slopes are less than 20
percent. The surface layer of the Lirios soil is brown silty
clay loam, and that of the Limones soil is dark yellowish
brown clay. These soils make up 10 to 20 percent of this
mapping unit.
Permeability and the available water capacity are
moderate. Runoff is rapid, and erosion is a hazard. Slip-
page is common in roadbanks, ditches, and drainageways.
This soil is difficult to work because it is steep. Hillside
ditches and diversions are difficult to lay out, establish,
and maintain. The root zone is deep. Natural fertility is
low. Crops respond well to heavy applications of lime and
fertilizers. Controlling erosion is the major concern of
management.
This soil has been used for taniers and plantains. It is
suited to pangolagrass, improved bermudagrass, Merker
grass, and molasses grass.
Proper stocking rates and deferred grazing, as well as
liming and fertilizing, are chief management needs.
This soil is suited to Honduras pine. Production of Hon-
duras pine is moderate, about 1200 board feet per acre
per year. The hazard of erosion and limitations on the use
of equipment are the major concerns of management.
Logging roads, skid trails, and planting should be on the
contour to help control erosion. The use of logging equip-
ment is restricted at times because the soil is soft and
slippery when wet. Brush removal, careful hand planting,
and fertilizing increase the survival of planted seedlings.


This soil is limited for most urban uses because it is
steep and subject to landslides. If the soil is used as con-
struction sites, development should be on the contour.
Removal of vegetation should be held to a minimum, and
temporary plant cover established quickly in denuded
areas. Capability subclass IVe.
JnD2-Juncal clay, 5 to 20 percent slopes, eroded.
This is a sloping to moderately steep, moderately well
drained soil on foot slopes and low rounded hills. Slopes
are concave and are 100 to 200 feet long. The areas range
from 10 to 100 acres.
Typically the surface layer is dark grayish brown, firm
clay about 10 inches thick. The subsoil is about 38 inches
thick; it is dark yellowish brown, yellowish brown, and
brownish yellow, firm clay. The substratum, beginning at
a depth of 48 inches, is brownish yellow, friable silty clay
loam.
Included with this soil in mapping are small areas of
Colinas soils. The surface layer of the Colinas soils is dark
brown clay loam. These soils make up 10 to 20 percent of
this mapping unit.
Permeability and the available water capacity are
moderate. Runoff is medium, and erosion is a hazard. This
soil is difficult to work because it is sloping to moderately
steep and because of the stickiness and plasticity of the
clay. Hillside ditches and diversions are difficult to lay
out, establish, and maintain. The root zone is deep. Natu-
ral fertility is medium. Crops respond to heavy applica-
tions of fertilizers. Controlling erosion is the major con-
cern of management.
This soil has been used for yams, taniers, and pigeon
peas. It is suited to pangolagrass, improved bermu-
dagrass, and Merker grass.
Proper stocking rates and grazing of pasture, as well as
fertilizing, are chief management needs.
This soil is suited to Honduras pine and Honduras
mahogany. Production of Honduras pine is moderate,
about 1200 board feet per acre per year. The hazard of
erosion is the major concern of management. All logging
roads, skid trails, and planting should be on the contour to
help control erosion. The use of logging equipment is
restricted at times because the soil is soft and slippery
when wet. Brush removal, careful hand planting,-and fer-
tilizing increase the survival of planted seedlings.
This soil is limited for most urban uses because it is
sloping to moderately steep. If the soil is used as con-
struction sites, development should be on the contour.
Removal of vegetation should be held to a minimum, and
temporary plant cover established quickly in denuded
areas. Capability subclass IIIe.
JuC-Juncos clay, 5 to 12 percent slopes. This is a
sloping, moderately well drained soil on side slopes and
foot slopes of strongly dissected uplands. Slopes are 100
to 500 feet long. The areas range from 5 to 100 acres.
Typically the surface layer is black, firm clay about 8
inches thick. The subsoil is about 10 inches thick; it is
dark brown, firm clay. The substratum, beginning at a
depth of 18 inches, is olive brown, firm clay. Volcanic rock
is at a depth of 40 inches.







SAN JUAN AREA, PUERTO RICO


Included with this soil in mapping are spots of Mabi
soils. The surface layer of the Mabi soils-is very dark
grayish brown clay. These soils make up 10 to 20 percent
of this mapping unit.
Permeability is slow, and the available water capacity is
moderate in this soil. Runoff is medium, and erosion is a
hazard. Slippage is common in roadbanks, ditches, and
drainageways. This soil is difficult to work because of
stickiness and plasticity of clay. The root zone is deep.
Natural fertility is high. Crops respond well to heavy ap-
plications of fertilizers. Controlling erosion is the major
concern of management.
This soil has been used for coffee, taniers, plantains,
and pigeon peas. It is suited to pangolagrass and Merker
grass.
Proper stocking rates and deferred grazing, as well as
liming and fertilizing, are chief management needs.
This soil is suited to Honduras pine, Eucalyptus
robusta, and Honduras mahogany. Production of Hondu-
ras pine is moderate, about 1000 board feet per acre per
year. The hazard of erosion is the major concern of
management. Logging roads, skid trails, and planting
should be on the contour to help control erosion. The use
of logging equipment is restricted at times because the
soil is soft and slippery when wet. Brush removal, careful
hand planting, and fertilizing increase the survival of
planted seedlings.
This soil is limited for most urban uses because of
slope, its clayey nature, and a high shrink-swell potential.
If the soil is used as construction sites, development
should be on the contour. Removal of the vegetation
should be held to a minimum, and temporary plant cover
established quickly in denuded areas. Capability subclass
IIIe.
JuD-Juncos clay, 12 to 20 percent slopes. This is a
moderately steep, moderately well drained soil on side
slopes and foot slopes of strongly dissected uplands.
Slopes are 100 to 300 feet long. The areas range from 5 to
100 acres.
Typically the surface layer is black, firm clay about 8
inches thick. The subsoil is about 10 inches thick; it is
dark brown, firm clay. The substratum, beginning at a
depth of 18 inches, is olive brown, firm clay. Volcanic rock
is at a depth of 40 inches.
Included with this soil in mapping are spots of Mabi
and Mucara soils. The surface layer of the Mabi and Mu-
cara soils is very dark grayish brown clay. These soils
make up 10 to 20 percent of this mapping unit.
Permeability is slow, and the available water capacity is
moderate. Runoff is rapid, and erosion is a hazard. Slip-
page is common in roadbanks, ditches, and drainageways.
This soil is difficult to work because of the slope and the
stickiness and plasticity of the clay. The root zone is deep.
Natural fertility is high. Crops respond well to heavy ap-
plications of fertilizers. Controlling erosion is the major
concern of management.
This soil has been used for coffee, taniers, plantains,
and pigeon peas. It is suited to pangolagrass and Merker
grass.


Proper stocking rates and deferred grazing, as well as
liming and fertilizing, are chief management needs.
This soil is suited to Honduras pine, Eucalyptus
robusta, and Honduras mahogany. Production of Hondu-
ras pine is moderate, about 1000 board feet per acre per
year. The hazard of erosion and limitations on the use of
equipment are the major concerns of management.
Logging roads, skid trails, and planting should be on the
contour to help control erosion. The use of logging equip-
ment is restricted at times because the soil is soft and
slippery when wet. Brush removal, careful hand planting,
and fertilizing increase the survival of planted seedlings.
This soil is limited for most urban uses because of
slope, its clayey nature, and a high shrink-swell potential.
If the soil is used as construction sites, development
should be on the contour. Removal of vegetation should
be held to a minimum, and temporary plant cover
established quickly in denuded areas. Capability subclass
IVe.
LaB-Lares clay, 2 to 5 percent slopes. This is a
gently sloping, somewhat poorly drained soil on terraces.
Slopes are smooth and are 200 to 800 feet long. The areas
range from 50 to 500 acres.
Typically the surface layer is dark brown, firm clay
about 6 inches thick. The subsoil is about 30 inches thick;
it is red and yellowish red, firm clay. The substratum,
beginning at a depth of 36 inches, is brownish yellow, red,
very pale brown, and dark yellowish brown, firm clay.
Included with this soil in mapping are spots of Daguey
soils. The surface layer of the Daguey soils is dark brown
clay. These soils make up 10 to 20 percent of this
mapping unit.
Permeability is moderately slow, and the available
water capacity is high. Runoff is slow. This soil is difficult
to work because of the stickiness and plasticity of the
clay. The root zone is deep. Natural fertility is medium.
Crops respond well to heavy applications of lime and fer-
tilizers. Controlling erosion is the major concern of
management.
This soil has been used for sugarcane, plantains, and
coffee. It is suited to pangolagrass and Merker grass.
Proper stocking rates and deferred grazing, as well as
liming and fertilizing, are chief management needs.
This soil is suited to Honduras pine, Honduras
mahogany, kadam, mahoe, and Eucalyptus robusta.
Production of Honduras pine is moderate, about 1300
board feet per acre per year. The hazard of erosion is
slight, and the limitations for the use of equipment is
moderate.
This soil is limited for most urban uses because it is too
clayey. Removal of vegetation should be held to a
minimum, and a temporary plant cover established
quickly in denuded areas. Capability subclass IIe.
LaC2-Lares clay, 5 to 12 percent slopes, eroded.
This is a sloping, somewhat poorly drained soil on ter-
races. Slopes are smooth and are 200 to 800 feet long. The
areas range from 50 to 500 acres. This soil has lost much
of its original surface layer through erosion.







OQTT OTRT'DTV


20

Typically the surface layer is dark brown, firm clay
about 6 inches thick. The subsoil is about 30 inches thick;
it is red and yellowish red, firm clay. The substratum,
beginning at a depth of 36 inches, is brownish yellow, red,
very pale brown, and dark yellowish brown, firm clay.
Included with this soil in mapping are spots of Daguey
soils. The surface layer of the Daguey soils is dark brown
clay. These soils make up 10 to 20 percent of this
mapping unit.
Permeability is moderately slow, and the available
water capacity is high. Runoff is medium. This soil is dif-
ficult to work because of the stickiness and plasticity of
the clay. The root zone is deep. Natural fertility is medi-
um. Crops respond well to heavy applications of lime and
fertilizers. Controlling erosion is the major concern of
management.
This soil has been used for sugarcane, plantains, and
coffee. It is suited to pangolagrass and Merker grass.
Proper stocking rates and deferred grazing of pasture,
as well as liming and fertilizing, are the chief manage-
ment needs (fig. 7).
This soil is suited to Honduras pine, Honduras
mahogany, kadam, mahoe, and Eucalyptus robusta.
Production of Honduras pine is moderate, about 1300
board feet per acre per year. The hazard of erosion is
slight, and the limitations on the use of equipment are
moderate.
This soil is limited for most urban uses because it is too
clayey. A temporary plant cover should be established
quickly in denuded areas. Capability subclass IIIe.
LmE-Limones clay, 20 to 40 percent slopes. This is a
steep, moderately well drained soil on side slopes and nar-
row ridgetops. Slopes are irregular and are 100 to 500
feet long. The areas are 10 to 200 acres.
Typically the surface layer is dark yellowish brown, fri-
able clay about 7 inches thick. The subsoil is about 41
inches thick; it is yellowish brown and red, firm clay. The
substratum, beginning at a depth of 48 inches, is red, fria-
ble clay saprolite.
Included with this soil in mapping are narrow ridges
that have less than 20 percent slopes and spots of Lirios
and Pandura soils. The surface layer of the Lirios soils is
brown silty clay loam, and that of the Pandura soil is dark
brown sandy loam. These soils make up 10 to 20 percent
of this mapping unit.
Permeability and the available water capacity are
moderate in this soil. Runoff is rapid, and erosion is a
hazard. Slippage is common in roadbanks, ditches, and
drainageways. The soil is difficult to work because it is
steep (fig. 8). Hillside ditches and diversions are difficult
to lay out, establish, and maintain. The root zone is deep.
Natural fertility is medium. Crops respond well to heavy
applications of lime and fertilizers. Controlling erosion is
the major concern of management.
This soil has been used for crops such as taniers, plan-
tains, and yams. It is suited to pangolagrass, improved
bermudagrass, Merker grass, and molasses grass.
Proper stocking rates and deferred grazing, as well as
liming and fertilizing, are chief management needs.


This soil is suited to Honduras pine. Production of Hon-
duras pine is moderate, about 1300 board feet per acre
per year. The hazard of erosion and limitations on the use
of equipment are the major concerns of management.
Logging roads, skid trails, and planting should be on the
contour to help control erosion. The use of logging equip-
ment is restricted at times because the soil is soft and
slippery when wet. Brush removal, careful hand planting,
and fertilizing increase the survival of planted seedlings.
This soil is limited for most urban uses because it is
steep and subject to landslides. If the soil is used as con-
struction sites, development should be on the contour.
Removal of vegetation should be held to a minimum, and
temporary plant cover established quickly in denuded
areas. Capability subclass IVe.
LmF-Limones clay, 40 to 60 percent slopes. This is a
very steep, moderately well drained soil on side slopes
and narrow ridgetops. Slopes are irregular and are 100 to
500 feet long. The areas range from 20 to 100 acres. A
few shallow to deep gullies have formed.
Typically the surface layer is dark yellowish brown, fri-
able clay about 7 inches thick. The subsoil is about 41
inches thick; it is yellowish brown and red, firm clay. The
substratum, beginning at a depth of 48 inches, is red, fria-
ble clay saprolite.
Included with this soil in mapping are some narrow
ridgetops where slopes are less than 40 percent. Also in-
cluded are spots of Lirios and Pandura soils. The surface
layer of the Lirios soils is brown silty clay loam, and that
of the Pandura soil is dark brown sandy loam. These soils
make up 10 to 20 percent of this mapping unit.
Permeability and the available water capacity are
moderate. Runoff is rapid, and erosion is a hazard. Slip-
page is common in roadbanks, ditches, and drainageways.
The soil is difficult to work because it is very steep. Hill-
side ditches and diversions are difficult to lay out,
establish, and maintain. The root zone is deep. Natural
fertility is medium. Crops respond well to heavy applica-
tions of lime and fertilizers. Controlling erosion is the
major concern of management.
This soil has been used for crops such as plantains,
yams, and taniers. It is suited to pangolagrass and im-
proved bermudagrass.
Proper stocking rates and deferred grazing, as well as
liming and fertilizing, are chief management needs.
This soil is suited to Honduras pine. Production of Hon-
duras pine is low, about 1000 board feet per acre per
year. The hazard of erosion and limitations on the use of
equipment are the major concerns of management.
Logging roads, skid trails, and planting should be on the
contour to help control erosion. The use of logging equip-
ment is restricted at times because the soil is soft and
slippery when wet. Brush removal, careful hand planting,
and fertilizing increase the survival of planted seedlings.
This soil is limited for most urban uses because it is
very steep and subject to landslides. If the soil is used as
construction sites, development should be on the contour.
Removal of vegetation should be held to a minimum, and


J 1. V AJ J






SAN JUAN AREA, PUERTO RICO


temporary plant cover established quickly in denuded
areas. Capability subclass Vie.
LoF2-Lirios silty clay loam, 20 to 60 percent slopes,
eroded. This is a steep to very steep, well drained soil on
side slopes and narrow ridgetops of the granitic humid
uplands. Slopes are irregular and are 100 to 300 feet long.
The areas range from 10 to 500 acres. This soil has lost
most of its original surface layer through erosion. A few
shallow and deep gullies have formed.
Typically the surface layer is brown, friable silty clay
loam about 4 inches thick. The subsoil is about 20 inches
thick; it is brown, friable silty clay loam in the upper part
and red, friable clay in the lower part. The substratum,
beginning at a depth of 24 inches, is variegated red, yel-
lowish red, yellowish brown, brown, very pale brown, and
white, friable clay and silty clay loam saprolite.
Included with this soil in mapping are small areas of
Pandura and Limones soils. The surface layer of the Pan-
dura soils is dark brown sandy loam, and that of the
Limones soils is dark yellowish brown clay. These soils
make up 10 to 20 percent of this mapping unit.
Permeability and the available water capacity are
moderate in this soil. Runoff is rapid, and erosion is a
hazard. Slippage is common in roadbanks, ditches, and
drainageways. This soil is difficult to work because it is
steep to very steep. Hillside ditches and diversions are
difficult to lay out, establish, and maintain. The root zone
is deep. Natural fertility is medium. Crops respond well
to heavy applications of lime and fertilizers. Controlling
erosion is the major concern of management.
This soil has been used for taniers, plantains, tobacco,
bananas, and sweet potatoes. It is suited to pangolagrass
and Merker grass.
Proper stocking rates and deferred grazing, as well as
liming and fertilizing, are chief management needs.
This soil is suited to Honduras pine and Eucalyptus
robusta trees. Production of Honduras pine is moderate,
about 1100 board feet per acre per year. The hazard of
erosion and limitations on the use of equipment are the
major concerns of management. Logging roads, skid
trails, and planting should be on the contour to help con-
trol erosion. The use of logging equipment is restricted at
times because the soil is soft and slippery when wet.
Brush removal, careful hand planting, and fertilizing in-
crease the survival of planted seedlings.
This soil is limited for most urban uses because it is
steep to very steep and subject to landslides. If the soil is
used as construction sites, development should be on the
contour. Removal of vegetation should be held to a
minimum, and temporary plant cover established quickly
in denuded areas. Capability subclass VIe.
LsE-Los Guineos clay, 20 to 40 percent slopes. This
steep, moderately well drained soil is on side slopes of
strongly dissected uplands. Slopes are irregular and are
300 to 1000 feet long. The areas range from 200 to 1000
acres. A few shallow gullies have formed.
Typically the surface layer is dark yellowish brown, fri-
able clay about 4 inches thick. The subsoil is about 44


inches thick; it is yellowish brown, red, and brownish yel-
low, firm clay with some white mottles in the lower part.
The substratum, beginning at a depth of 48 inches, is red,
friable clay saprolite mottled with brownish yellow, yel-
low, and white.
Included with this soil in mapping are some rounded
hilltops and narrow foot slopes where slopes are less than
20 percent Also included are spots of Humatas, Consumo,
and Naranjito soils. The surface layer of the Humatas
soils is dark brown clay and that of the Naranjito soils is
brown to dark brown silty clay loam. The surface layer of
the Consumo soils is reddish brown clay. These soils make
up 10 to 20 percent of this mapping unit.
Permeability is moderately slow, and the available
water capacity is high in this soil. Runoff is rapid, and
erosion is a hazard. Slippage is common in roadbanks,
ditches, and drainageways. This soil is difficult to work
because it is steep and because of the stickiness and
plasticity of the clay. Hillside ditches and diversions are
difficult to lay out, establish, and maintain. The root zone
is deep. Natural fertility is medium. Crops respond well
to heavy applications of lime and fertilizers. Controlling
erosion is the major concern of management.
This soil has been used for coffee and bananas. It is
suited to pangolagrass.
Proper stocking rates and deferred grazing, as well as
liming and fertilizing, are chief management needs.
This soil is suited to Honduras pine and Eucalyptus
robusta. Production of Honduras pine is moderate, about
1400 board feet per acre per year. The hazard of erosion
and limitations on the use of equipment are the major
concerns of management. Logging roads, skid trails, and
planting should be on the contour to help control erosion.
The use of logging equipment is restricted at times
because the soil is soft and slippery when wet. Brush
removal, careful hand planting, and fertilizing increase the
survival of plant seedlings.
This soil is limited for most urban uses because it is
steep and subject to landslides. If the soil is used as con-
struction sites, development should be on the contour.
Removal of vegetation should be held to a minimum, and
temporary plant cover established quickly in denuded
areas. Capability subclass VIe.
LsF-Los Guineos clay, 40 to 60 percent slopes. This
is a very steep, moderately well drained soil on side
slopes of strongly dissected uplands. Slopes are irregular
and are 200 to 800 feet long. The areas range from 200 to
1000 acres. A few shallow gullies have formed.
Typically the surface layer is dark yellowish brown, fri-
able clay about 4 inches thick. The subsoil is about 44
inches thick; it is yellowish brown, red, and brownish yel-
low, firm clay with some white mottles in the lower part.
The substratum, beginning at a depth of 48 inches, is red,
friable clay saprolite mottled with brownish yellow, yel-
low, and white.
Included with this soil in mapping are some hilltops
where slopes are less than 40 percent and some very
steep ridges where they are more than 60 percent. Also







SOIL SURVEY


included are spots of Consumo soils. The surface layer of
the Consumo soils is reddish brown clay. These soils make
up 10 to 20 percent of this mapping unit.
Permeability is moderately slow, and the available
water capacity is high. Runoff is very rapid, and erosion
is a hazard. Slippage is common in roadbanks, ditches, and
drainageways. This soil is difficult to work because it is
very steep and because of the stickiness and plasticity of
the clay. Hillside ditches and diversions are difficult to
lay out, establish, and maintain. The root zone is deep.
Natural fertility is medium. Crops respond well to heavy
applications of lime and fertilizers. Controlling erosion is
the major concern of management.
This soil has been used for coffee and bananas.
This soil is suited to Honduras pine and Eucalyptus
robusta. Production of Honduras pine is low, about 1000
board feet per acre per year. The hazard of erosion and
limitations on the use of equipment are the major con-
cerns of management. Logging roads, skid trails, and
planting should be on the contour to help control erosion.
The use of logging equipment is restricted at times
because the soil is soft and slippery when wet. Brush
removal, careful hand planting, and fertilizing increase
the survival of plant seedlings.
This soil is limited for most urban uses because it is
very steep and subject to landslides. If the soil is used as
construction sites, development should be on the contour.
Removal of vegetation should be held to a minimum, and
temporary plant cover established quickly in denuded
areas. Capability subclass VIIe.
MaA-Mabi clay, 0 to 2 percent slopes. This is a
nearly level, somewhat poorly drained soil on alluvial fans
and terraces above the river flood plains. Slopes are
smooth and are 100 to 300 feet long. The areas range
from 10 to 50 acres.
Typically the surface layer is very dark grayish brown,
very firm clay about 7 inches thick. The subsoil is about
17 inches thick; it is dark yellowish brown and yellowish
brown, very firm clay mottled with gray. The substratum,
beginning at a depth of 24 inches, is yellowish brown,
very firm clay mottled with gray and greenish gray.
Included with this soil in mapping are small areas of
Montegrande soils. The surface layer of the Montegrande
soils is very dark grayish brown clay. These soils make up
10 to 20 percent of this mapping unit.
Permeability is slow, and the available water capacity is
high. Runoff is slow. This soil is difficult to work because
of the stickiness and plasticity of the clay. The root zone
is deep. Natural fertility is high. Crops respond well to
heavy applications of fertilizers.
This soil has been used for sugarcane. It is suited to
pangolagrass, improved bermudagrass, and Merker grass.
Proper stocking rates and deferred grazing, as well as
liming and fertilizing, are chief management needs.
This soil is limited for most urban uses because of the
high shrink-swell potential (fig. 9) and the flood hazard.
Capability subclass IIw.


MaB-Mabi clay, 2 to 5 percent slopes. This is a
gently sloping, somewhat poorly drained soil on alluvial
fans and terraces above the river flood plains. Slopes are
gently undulating and are 100 to 300 feet long. The areas
range from 10 to 100 acres.
Typically the surface layer is very dark grayish brown,
very firm clay about 7 inches thick. The subsoil is about
17 inches thick; it is dark yellowish brown and yellowish
brown, very firm clay mottled with gray. The substratum,
beginning at a depth of 24 inches, is yellowish brown,
very firm clay mottled with gray and greenish gray.
Included with this soil in mapping are small areas of
Montegrande soils. The surface layer of the Montegrande
soils is very dark grayish brown clay. These soils make up
10 to 20 percent of the areas of this mapping unit.
Permeability is slow, and the available water capacity is
high. Runoff is slow. This soil is difficult to work because
of the stickiness and plasticity of the clay. The root zone
is deep. Natural fertility is high. Crops respond well to
heavy applications of fertilizers.
This soil has been used for sugarcane. It is suited to
pangolagrass, improved bermudagrass, and Merker grass.
Proper stocking rates and deferred grazing, as well as
liming and fertilizing, are chief management needs.
This soil is limited for most urban uses because of the
high shrink-swell potential and the flood hazard. Capabili-
ty subclass IIw.
MaC-Mabi clay, 5 to 12 percent slopes. This is a
sloping, somewhat poorly drained soil on alluvial fans and
terraces above the river flood plains. Slopes are undulat-
ing and are 100 to 200 feet long. The areas range from 10
to 50 acres.
Typically the surface layer is very dark grayish brown,
very firm clay about 7 inches thick. The subsoil is about
17 inches thick; it is dark yellowish brown and yellowish
brown, very firm clay mottled with gray. The substratum,
beginning at a depth of 24 inches, is yellowish brown,
very firm clay mottled with gray and greenish gray.
Included with this soil in mapping are small areas of
Montegrande soils. The surface layer of the Montegrande
soils is very dark grayish brown clay. These soils make up
20 percent of this mapping unit.
Permeability is slow, and the available water capacity is
high. Runoff is slow. This soil is difficult to work because
of the stickiness and plasticity of the clay. The root zone
is deep. Natural fertility is high. Crops respond well to
heavy applications of fertilizers.
This soil has been used for sugarcane. It is suited to
pangolagrass, improved bermudagrass, and Merker grass.
Proper stocking rates and deferred grazing, as well as
fertilizing, are chief management needs.
This soil is limited for most urban uses because of the
high shrink-swell potential and the flood hazard. Capabili-
ty subclass IIIe.
Md-Made land. Made land consists of areas that have
been covered with gravel, rock, concrete blocks, and other
debris. It has been built up for industrial uses and is not
suited to farming.






SAN JUAN AREA, PUERTO RICO


MIF-Malaya clay loam, 40 to 60 percent slopes. This
is a very steep, well drained soil on side slopes of
strongly dissected volcanic uplands. Slopes are irregular
and are 100 to 300 feet long. The areas range from 10 to
100 acres. A few shallow and deep gullies have formed.
Typically the surface layer is dark brown, friable clay
about 6 inches thick. The subsoil is about 7 inches thick; it
is dark brown, firm gravelly clay. The substratum,
beginning at a depth of 13 inches, is dark yellowish
brown, firm gravelly clay loam. Bedrock is at a depth of
18 inches.
Included with this soil in mapping are spots of Caguabo
soils. The surface layer of the Caguabo soils is dark gray-
ish brown clay loam. These soils make up 10 to 20 percent
of this mapping unit.
Permeability is moderate, and the available water
capacity is low. Runoff is very rapid, and erosion is a
hazard. Slippage is common in roadbanks, ditches, and
drainageways. This soil is fertile, but is difficult to work
because it is very steep. Hillside ditches and diversions
are difficult to lay out, establish, and maintain. The root
zone is shallow. Controlling erosion is the major concern
of management.
This soil has been in brush and brushy pasture most of
the time. It is suited to pangolagrass.
Proper stocking rates and deferred grazing, as well as
fertilizing, are chief management needs.
This soil is suited to Honduras pine and Eucalyptus
robusta trees. Production of Honduras pine is very low,
about 700 board feet per acre per year. The hazard of
erosion and limitations on the use of equipment are the
major concerns of management. Logging roads, skid
trails, and planting should be on the contour to help con-
trol erosion. The use of logging equipment is restricted at
times because the soil is soft and slippery when wet.
Brush removal, careful hand planting, and fertilizing in-
crease the survival of planted seedlings.
This soil is limited for most urban uses because it is
very steep and subject to landslides. If the soil is used as
construction sites, development should be on the contour.
Removal of vegetation should be held to a minimum, and
temporary plant cover established quickly in denuded
areas. Capability subclass VIIs.
MoF-Maricao clay, 20 to 60 percent slopes. This is a
steep to very steep, well drained soil on side slopes and
narrow hilltops of the strongly dissected uplands. Slopes
are irregular and are 300 to 800 feet long. The areas
range from 20 to 500 acres. A few shallow and deep gul-
lies have formed.
Typically the surface layer is reddish brown, friable
clay about 6 inches thick. The subsoil is about 16 inches
thick; it is red, friable clay in the upper part and silty
clay in the lower part. The substratum, beginning at a
depth of 22 inches, is red, strong brown, and pale brown,
friable silty clay loam saprolite.
Included with this soil in mapping are spots of Consu-
mo soils. Also included are some very severely eroded
ridgetops. The surface layer of the Consumo soils is red-


dish brown clay. These soils make up 10 to 20 percent of
this mapping unit.
Permeability and the available water capacity are
moderate. Runoff is very rapid, and erosion is a hazard.
Slippage is common in roadbanks, ditches, and
drainageways. This soil is difficult to work because it is
steep to very steep and because of the stickiness and
plasticity of the clay. Hillside ditches and diversions are
difficult to lay out, establish, and maintain. The root zone
is deep. Natural fertility is medium. Crops respond well
to heavy applications of lime and fertilizers. Controlling
erosion is the major concern of management.
This soil has been in brush and brushy pasture. It is
suited to pangolagrass.
Proper stocking rates and deferred grazing, as well as
liming and fertilizing, are chief management needs.
This soil is suited to Honduras pine and Eucalyptus
robusta trees. Production of Honduras pine is moderate,
about 1300 board feet per acre per year. The hazard of
erosion and limitations on the use of equipment are the
major concerns of management. Logging roads, skid
trails, and planting should be on the contour to help con-
trol erosion. The use of logging equipment is restricted at
times because the soil is soft and slippery when wet.
Brush removal, careful hand planting, and fertilizing in-
crease the survival of planted seedlings.
This soil is limited for most urban uses because it is
steep to very steep and subject to landslides. If the soil is
used as construction sites, development should be on the
contour. Removal of vegetation should be held to a
minimum, and temporary plant cover established quickly
in denuded areas. Capability subclass VIIe.
Mp-Martin Pena muck. This is a nearly level, very
poorly drained soil in low depressional areas of the humid
coastal plains and river flood plains. The areas range from
10 to 800 acres.
Typically the surface layer is black muck about 8 inches
thick. The underlying material is mostly mottled very
dark brown and greenish gray clay.
Included with this soil in mapping are spots of Saladar
and Bajura soils. The surface layer of the Saladar soils is
black muck, and that of the Bajura soils is dark brown
clay. These soils make up 10 to 20 percent of this
mapping unit.
Permeability is very slow and the available water
capacity is very high. Runoff is slow. This soil is very dif-
ficult to work because of wetness. A very complex and
expensive drainage system is needed if it is to be reclaimed.
This soil has been in cattails, sedges, papyrus, and other
hydrophytic vegetation most of the time. It is suited to
paragrass.
This soil is limited for most urban uses because of wet-
ness, slow permeability, and the flood hazard. Capability
subclass VIIw.
MsB-Matanzas clay, 2 to 5 percent slopes. This is a
gently sloping, well drained soil on foot slopes and in
small valleys between the limestone hills. Slopes are







SOIL SURVEY


gently undulating and are 200 to 1000 feet long. The areas
range from 10 to 300 acres.
Typically the surface layer is dark reddish brown, firm
clay about 7 inches thick. The subsoil is about 46 inches
thick; it is dark reddish brown and red, friable clay.
Limestone bedrock is at a depth of 53 inches.
Included with this soil in mapping are some spots of
Bayamon soils. The surface layer of the Bayamon soils is
dark reddish brown clay. These soils make up 10 to 20
percent of this mapping unit.
Permeability and the available water capacity are
moderate. Runoff is slow. This soil is difficult to work.
The root zone is deep. Natural fertility is medium. Crops
respond well to heavy applications of lime and fertilizers.
This soil has been used for crops such as plantains,
yams, and taniers. It is suited to pangolagrass, Merker
grass, and paragrass.
Proper stocking rates and deferred grazing, as well as
liming and fertilizing, are chief management needs.
This soil has limitations for most urban uses because of
its clayey nature. Removal of vegetation should be held to
a minimum, and temporary plant cover established
quickly in denuded areas. Capability subclass IIe.
MtB-Montegrande clay, 2 to 5 percent slopes. This
is a gently sloping, moderately well drained soil on alluvi-
al fans and foot slopes of the volcanic uplands. Slopes are
smooth and are 100 to 300 feet long. The areas range
from 30 to 50 acres.
Typically the surface layer is very dark grayish brown,
firm clay about 7 inches thick. The subsoil is about 14
inches thick; it is dark brown and grayish brown, firm
clay mottled with yellowish brown, gray, and greenish
gray. The substratum from a depth of 21 inches to 29
inches is mixed dark yellowish brown and yellowish
brown, firm clay. From 29 inches to 48 inches it is brown
and yellowish brown very gravelly clay.
Included with this soil in mapping are spots of Mabi
soils. The surface layer of the Mabi soils is very dark
grayish brown, very firm clay. These soils make up 10 to
20 percent of this mapping unit.
Permeability is moderately slow, and the available
water capacity is moderate. Runoff is medium. This soil is
difficult to work because of the stickiness and plasticity
of the clay. The root zone is deep. Natural fertility is
high. Crops respond well to heavy applications of fertil-
izers. ,
This soil has been used for sugarcane.
This soil is limited for most urban uses because of its
clayey nature, the high shrink-swell potential, and the
flood hazard. Removal of vegetation should be held to a
minimum, and temporary plant cover established quickly
in denuded areas. Capability subclass IIw.
MtC-Montegrande clay, 5 to 12 percent slopes. This
is a sloping, moderately well drained soil on alluvial fans
and foot slopes of the volcanic uplands. Slopes are undu-
lating and are 100 to 200 feet long. The areas range from
20 to 40 acres.


Typically the surface layer is very dark grayish brown,
firm clay about 7 inches thick. The subsoil is about 14
inches thick; it is dark brown and grayish brown, firm
clay mottled with yellowish brown, gray, and greenish
gray. The substratum from a depth of 21 inches to 29
inches is mixed dark yellowish brown and yellowish
brown, firm clay. From 29 inches to 48 inches it is brown
and yellowish brown very gravelly clay.
Included with this soil in mapping are spots of Mabi
soils. The surface layer of the Mabi soils is very dark
grayish brown, very firm clay. These soils make up 10 to
20 percent of this mapping unit.
Permeability is moderately slow, and the available
water capacity is moderate. Runoff is medium, and ero-
sion is a hazard. This soil is difficult to work because of
stickiness and plasticity of the clay. The root zone is deep.
Natural fertility is high. Crops respond well to heavy ap-
plications of fertilizers. Controlling erosion is the major
concern of management.
This soil has been used for sugarcane.
This soil is limited for most urban uses because of
slope, clayey nature, and high shrink-swell potential.
Capability subclass IIIe.
MuF2-Morado clay loam, 40 to 60 percent slopes,
eroded. This is a very steep, well drained soil on side
slopes, foot slopes, and hilltops of strongly dissected
humid uplands. Slopes are irregular and are 200 to 1000
feet long. The areas range from 70 to 500 acres. This soil
has lost most of its original surface layer through erosion.
A few shallow and deep gullies have formed.
Typically the surface layer is weak red, friable clay
loam about 8 inches thick. The subsoil is about 18 inches
thick; it is reddish gray, dark reddish gray, red, weak red,
and strong brown, friable clay loam. The substratum,
beginning at a depth of 26 inches is variegated gray, light
gray, and dark reddish gray clay loam saprolite. Bedrock
is at a depth of 34 inches.
Included with this soil in mapping are spots of Caguabo
soils. The surface layer of the Caguabo soils is dark gray-
ish brown clay loam. These soils make up 10 to 20 percent
of this mapping unit.
Permeability and the available water capacity are
moderate. Runoff is very rapid, and erosion is a hazard.
Slippage is common in roadbanks, ditches, and
drainageways. This soil is difficult to work because it is
very steep. Hillside ditches and diversions are difficult to
lay out, establish, and maintain. The root zone is
moderately deep. Fertility is high. Controlling erosion is
the major concern of management.
This soil has been in brushy forest and brushy pasture
most of the time. It is suited to pangolagrass and Merker
grass.
Proper stocking rates and deferred grazing, as well as
fertilizing, are chief management needs.
This soil is suited to Honduras pine and Eucalyptus
robusta trees. Production of Honduras pine is low, about
900 board feet per acre per year. The hazard of erosion
and limitations on the use of equipment are the major







SAN JUAN AREA, PUERTO RICO


concerns of management. Logging roads, skid trails, and
planting should be on the contour to help control erosion.
The use of logging equipment is restricted at times
because the soil is soft and slippery when wet. Brush
removal, careful hand planting, and fertilizing increase
the survival of planted seedlings.
This soil is limited for most urban uses because it is
very steep and subject to landslides. If the soil is used as
construction sites, development should be on the contour.
Removal of vegetation should be held to a minimum, and
temporary plant cover established quickly in denuded
areas. Capability subclass VIIe.
MxD-Mucara clay, 12 to 20 percent slopes. This is a
moderately steep, well drained soil on foot slopes, side
slopes, and rounded hilltops of strongly dissected uplands.
Slopes are irregular and are 300 to 800 feet long. The
areas range from 20 to 100 acres.
Typically the surface layer is very dark grayish brown,
firm clay about 5 inches thick. The subsoil is about 7
inches thick; it is dark brown, firm clay. The substratum,
beginning at a depth of 12 inches, is highly weathered
volcanic rock. Bedrock is at a depth of 30 inches.
Included with this soil in mapping are spots of Juncos
and Naranjito soils. The surface layer of the Juncos soils
is black clay, and that of the Naranjito soils is brown to
dark brown silty clay loam. These soils make up 10 to 20
percent of this mapping unit.
Permeability and the available water capacity are
moderate. Runoff is rapid, and erosion is a hazard. Slip-
page is common in roadbanks, ditches, and drainageways.
This soil is difficult to work because it is moderately
steep and because of the stickiness and plasticity of the
clay. Hillside ditches and diversions are difficult to lay
out, establish, and maintain. The root zone is moderately
deep. This soil is fertile. Crops respond well to heavy ap-
plications of lime and fertilizers. Controlling erosion is the
major concern of management.
This soil has been used for crops such as coffee, taniers,
plantains, and pigeon peas. It is suited to pangolagrass
and Merker grass.
Proper stocking rates and deferred grazing, as well as
liming and fertilizing, are chief management needs.
This soil is suited to Honduras pine, Eucalyptus
robusta, and Honduras mahogany. Production of the Hon-
duras pine is low, about 1000 board feet per acre per
year. The hazard of erosion and limitations on the use of
equipment are the major concerns of management.
Logging roads, skid trails, and planting should be on the
contour to help control erosion. The use of logging equip-
ment is restricted at times because the soil is soft and
slippery when wet. Brush removal, careful hand planting,
and fertilizing increase the survival of planted seedlings.
This soil is limited for most urban uses because it is
moderately steep. If the soil is used as construction sites,
development should be on the contour. Removal of
vegetation should be held to a minimum, and temporary
plant cover established quickly in denuded areas. Capa-
bility subclass IVe.


MxE-Mucara clay, 20 to 40 percent slopes. This is a
steep, well drained soil on side slopes and rounded hill-
tops of strongly dissected uplands. Slopes are irregular
and are 200 to 1000 feet long. The areas range from 100
to 500 acres. A few shallow and deep gullies have formed.
Typically the surface layer is very dark grayish brown,
firm clay about 5 inches thick. The subsoil is about 7
inches thick; it is dark brown, firm clay. The substratum,
beginning at a depth of 12 inches, is highly weathered
volcanic rock. Bedrock is at a depth of 30 inches.
Included with this soil in mapping are spots of Caguabo
and Naranjito soils. Also included are some hilltops that
have many rocks and boulders on the surface. The surface
layer of the Caguabo soils is dark grayish brown clay
loam, and that of the Naranjito soils is brown to dark
brown silty clay loam. These soils make up 10 to 20 per-
cent of this mapping unit.
Permeability is moderate, and the available water
capacity is low. Runoff is very rapid, and erosion is a
hazard. Slippage is common in roadbanks, ditches, and
drainageways. This soil is difficult to work because it is
steep and because of the stickiness and plasticity of the
clay. Hillside ditches and diversions are difficult to lay
out, establish, and maintain. The root zone is moderately
deep. The soil is fertile. Controlling erosion is the major
concern of management.
This soil has been in brush and brushy pasture. It is
suited to-pangolagrass.
Proper stocking rates and deferred grazing, as well as
liming and fertilizing, are chief management needs. This
soil is suited to Honduras pine and Eucalyptus robusta.
Production of Honduras pine is low, about 900 board feet
per acre per year. The hazard of erosion and limitations
on the use of equipment are the major concerns of
management. Logging roads, skid trails, and planting
should be on the contour to help control erosion. The use
of logging equipment is restricted at times because the
soil is soft and slippery when wet. Brush removal, careful
hand planting, and fertilizing increase the survival of
planted seedlings.
This soil is limited for most urban uses because it is
steep and is shallow to rock. If the soil is used as con-
struction sites, development should be on the contour.
Removal of vegetation should be held to a minimum, and
temporary plant cover established quickly in denuded
areas. Capability subclass VIe.
MxF-Mucara clay, 40 to 60 percent slopes. This is a
very steep, well drained soil on side slopes and rounded
hilltops of strongly dissected uplands. Slopes are irregular
and are 100 to 800 feet long. The areas range from 100 to
1000 acres. A few shallow and deep gullies have formed.
Typically the surface layer is very dark grayish brown,
firm clay about 5 inches thick. The subsoil is about 7
inches thick; it is dark brown, firm clay. The substratum,
beginning at a depth of 12 inches, is highly weathered
volcanic rock. Bedrock is at a depth of 30 inches.
Included with this soil in mapping are spots of Caguabo
and Naranjito soils. Also included are some hilltops that







SOIL SURVEY


have many rocks and boulders on the surface. The surface
layer of the Caguabo soils is dark grayish brown clay
loam, and that of the Naranjito soils is brown to dark
brown silty clay loam. These soils make up 10 to 20 per-
cent of this mapping unit.
Permeability is moderate, and the available water
capacity is low. Runoff is very rapid, and erosion is a
hazard. Slippage is common in roadbanks, ditches, and
drainageways. This soil is difficult to work because it is
very steep and because of the stickiness and plasticity of
the clay. Hillside ditches and diversions are difficult to
lay out, establish, and maintain. The root zone is
moderately deep. This soil is fertile. Controlling erosion is
the major concern of management.
This soil has been in brush and brushy pasture. It is
suited to pangolagrass.
Proper stocking rates and grazing of pasture, as well as
liming and fertilizing, are chief management needs.
This soil is suited to Honduras pine and Eucalyptus
robusta. Production of Honduras pine is low, about 900
board feet per acre per year. The hazard of erosion and
limitations on the use of equipment are the major con-
cerns of management. Logging roads, skid trails, and
planting should be on the contour to help control erosion.
The use of logging equipment is restricted at times
because the soil is soft and slippery when wet. Brush
removal, careful hand planting, and fertilizing increase
the survival of plant seedlings.
This soil is limited for most urban uses because it is
very steep and it is shallow to rock. If the soil is used as
construction sites, development should be on the contour.
Removal of vegetation should be held to a minimum, and
temporary plant cover established quickly in denuded
areas. Capability subclass VIIe.
NaD2-Naranjito silty clay loam, 12 to 20 percent
slopes, eroded. This is a moderately steep, well drained
soil on strongly dissected volcanic uplands. Slopes are ir-
regular and are 100 to 500 feet long. The areas range
from 20 to 200 acres. This soil has lost most of its original
surface layer through erosion. A few shallow and deep
gullies have formed.
Typically the surface layer is brown to dark brown, fri-
able silty clay loam about 4 inches thick. The subsoil is
about 20 inches thick; it is reddish brown and yellowish
red firm clay. The substratum, beginning at a depth of 24
inches, is variegated yellowish red, red, and light yel-
lowish brown, friable, clay loam saprolite. Bedrock is at a
depth of 40 inches.
Included with this soil in mapping are spots of Mucara
and Consumo soils. The surface layer of the Mucara soils
is very dark grayish brown clay and that of the Consumo
soils is reddish brown clay. These soils make up 10 to 20
percent of the areas of this mapping unit.
Permeability and the available water capacity are
moderate in this soil. Runoff is rapid, and erosion is a
hazard. Slippage is common in roadbanks, ditches, and
drainageways. This soil is difficult to work because it is
moderately steep. Hillside ditches and diversions are dif-


ficult to lay out, establish, and maintain. The root zone is
moderately deep. Natural fertility is medium. Crops
respond well to heavy applications of lime and fertilizers.
Controlling erosion is the major concern of management.
This soil has been used for crops such as plantains and
bananas. It is suited to pangolagrass and Merker grass.
Proper stocking rates and deferred grazing, as well as
liming and fertilizing, are chief management needs.
This soil is suited to Honduras pine, Honduras
mahogany, kadam, mahoe, and Eucalyptus robusta trees.
Production of Honduras pine is moderate, about 1100
board feet per acre per year. The hazard of erosion and
limitations on the use of equipment are the major con-
cerns of management. Logging roads, skid trails, and
planting should be on the contour to help control erosion.
The use of logging equipment is restricted at times
because the soil is soft and slippery when wet. Brush
removal, careful hand planting, and fertilizing increase
the survival of planted seedlings.
This soil is limited for most urban uses because it is
moderately steep and is subject to landslides. If the soil is
used as construction sites, development should be on the
contour. Removal of vegetation should be held to a
minimum, and temporary plant cover established quickly
in denuded areas. Capability subclass IVe.
NaE2-Naranjito silty clay loam, 20 to 40 percent
slopes, eroded. This is a steep, well drained soil on
strongly dissected uplands. Slopes are irregular and are
100 to 400 feet long. The areas range from 50 to 100
acres. This soil has lost most of its original surface layer
through erosion. A few shallow and deep gullies have
formed.
Typically the surface layer is brown to dark brown, fri-
able silty clay loam about 4 inches thick. The subsoil is
about 20 inches thick; it is reddish brown and yellowish
red, firm clay. The substratum, beginning at a depth of 24
inches, is variegated yellowish red, red, and light yel-
lowish brown, friable, clay loam saprolite.
Included with this soil in mapping are spots of Mucara
and Caguabo soils. The surface layer of the Mucara soils
is very dark grayish brown clay, and that of the Caguabo
soils is dark grayish brown clay loam. These soils make
up 10 to 20 percent of this mapping unit.
Permeability is moderate, and the available water
capacity is low. Runoff is rapid, and erosion is a hazard.
Slippage is common in roadbanks, ditches, and
drainageways. This soil is difficult to work because it is
steep and because of the stickiness and plasticity of the
clay. Hillside ditches and diversions are difficult to lay
out, establish, and maintain. The root zone is moderately
deep. Natural fertility is medium. Crops respond well to
heavy applications of lime and fertilizers. Controlling ero-
sion is the major concern of management.
This soil has been in brush and brushy pasture. It is
suited to pangolagrass.
Proper stocking rates and deferred grazing, as well as
liming and fertilizing, are chief management needs.







SAN JUAN AREA, PUERTO RICO


This soil is suited to Honduras pine, Honduras
mahogany, kadam, mahoe, and Eucalyptus robusta trees.
Production of Honduras pine is moderate, about 1100
board feet per acre per year. The hazard of erosion and
limitations on the use of equipment are the major con-
cerns of management. Logging roads, skid trails, and
planting should be on the contour to help control erosion.
The use of logging equipment is restricted at times
because the soil is soft and slippery when wet. Brush
removal, careful hand planting, and fertilizing increase
the survival of planted seedlings.
This soil is limited for most urban uses because it is
steep and is subject to landslides. If the soil is used as
construction sites, development should be on the contour.
Removal of vegetation should be held to a minimum, and
temporary plant cover established quickly in denuded
areas. Capability subclass VIe.
NaF2-Naranjito silty clay loam, 40 to 60 percent
slopes, eroded. This is a very steep, well drained soil on
strongly dissected uplands. Slopes are irregular and are
200 to 800 feet long. The areas range from 30 to 1000
acres. This soil has lost most of its original surface layer
through erosion. A few shallow and deep gullies have
formed.
Typically the surface layer is brown to dark brown, fri-
able silty clay loam about 4 inches thick. The subsoil is
about 20 inches thick; it is reddish brown and yellowish
red, firm clay. The substratum, beginning at a depth of 24
inches, is variegated yellowish red, red, and light yel-
lowish brown, friable, clay loam saprolite.
Included with this soil in mapping are spots of Mucara
and Caguabo soils. The surface layer of the Mucara soils
is very dark grayish brown clay, and that of the Caguabo
soils is dark grayish brown clay loam. These soils make
up 10 to 20 percent of this mapping unit.
Permeability is moderate, and the available water
capacity is low. Runoff is rapid, and erosion is a hazard.
Slippage is common in roadbanks, ditches, and
drainageways. This soil is difficult to work because it is
very steep and because of the stickiness and plasticity of
the clay. Hillside ditches and diversions are difficult to
lay out, establish, and maintain. The root zone is
moderately deep. Natural fertility is medium. Controlling
erosion is the major concern of management.
This soil has been in brush and brushy pasture. It is
suited to pangolagrass.
Proper stocking rates and deferred grazing, as well as
liming and fertilizing, are chief management needs.
This soil is suited to Honduras pine and Eucalyptus
robusta trees. Production of Honduras pine is low, about
900 board feet per acre per year. The hazard of erosion
and limitations on the use of equipment are the major
concerns of management. Logging roads, skid trails, and
planting should be on the contour to help control erosion.
The use of logging equipment is restricted at times
because the soil is soft and slippery when wet. Brush
removal, careful hand planting, and fertilizing increase
the survival of planted seedlings.


This soil is limited for most urban uses because it is
very steep and is subject to landslides. If the soil is used
as construction sites, development should be on the con-
tour. Removal of vegetation should be held to a minimum,
and temporary plant cover established quickly in denuded
areas. Capability subclass VIIe.
PaD-Pandura sandy loam, 12 to 20 percent slopes.
This is a moderately steep, well drained soil on side
slopes of dissected uplands. Slopes are irregular and are
100 to 300 feet long. The areas range from 10 to 300
acres.
Typically the surface layer is dark brown, friable sandy
loam about 7 inches thick. The subsoil is about 5 inches
thick; it is dark yellowish brown, friable sandy loam. The
substratum, beginning at a depth of 12 inches, is very
pale brown, pale brown, dark yellowish brown, and white
sandy loam saprolite.
Included with this soil in mapping are spots of Limones
and Jagueyes soils. The surface layer of the Limones soils
is dark yellowish brown clay, and that of the Jagueyes
soils is dark yellowish brown loam. These soils make up
10 to 20 percent of this mapping unit.
Permeability is moderate, and the available water
capacity is low. Runoff is medium, and erosion is a
hazard. Slippage is common in roadbanks, ditches, and
drainageways. This soil is difficult to work because it is
moderately steep. Hillside ditches and diversions are dif-
ficult to lay out, establish, and maintain. The root zone is
shallow. Natural fertility is medium. Crops respond well
to heavy applications of lime and fertilizers. Controlling
erosion is the major concern of management.
This soil has been in brush and brushy pasture. It is
suited to pangolagrass and Merker grass.
Proper stocking rates and deferred grazing, as well as
liming and fertilizing, are chief management needs.
This soil is suited to Honduras pine, Eucalyptus
robusta, and mahoe trees. Production of Honduras pine is
moderate, about 1200 board feet per acre per year. The
hazard of erosion and limitations on the use of equipment
are the major concerns of management. Logging roads,
skid trails, and planting should be on the contour to help
control erosion. Brush removal, careful hand planting, and
fertilizing increase the survival of planted seedlings.
This soil is limited for most urban uses because it is
moderately steep and shallow to rock. If the soil is used
as construction sites, development should be on the con-
tour. Removal of vegetation should be held to a minimum,
and temporary plant cover established quickly in denuded
areas. Capability subclass IVe.
PaE-Pandura sandy loam, 20 to 40 percent slopes.
This is a steep, well drained soil on side slopes of dis-
sected uplands. Slopes are irregular and are 100 to 400
feet long. The areas range from 50 to 500 acres.
Typically the surface layer is dark brown, friable sandy
loam about 7 inches thick. The subsoil is about 5 inches
thick; it is dark yellowish brown, friable sandy loam. The
substratum, beginning at a depth of 12 inches, is very
pale brown, pale brown, dark yellowish brown, and white
sandy loam saprolite.







SOIL SURVEY


Included with this soil in mapping are spots of Limones
and Jagueyes soils. Also included are a few spots of rock
land. The surface layer of the Limones soils is dark yel-
lowish brown clay and that of the Jagueyes soils is dark
yellowish brown loam. These soils make up 10 to 20 per-
cent of this mapping unit.
Permeability is moderate, and the available water
capacity is low. Runoff is rapid, and erosion is a hazard.
Slippage is common in roadbanks, ditches, and
drainageways. This soil is difficult to work because it is
steep. Hillside ditches and diversions are difficult to lay
out, establish, and maintain. The root zone is shallow.
Natural fertility is medium. Controlling erosion is the
major concern of management.
This soil has been in brush and brushy pasture. It is
suited to pangolagrass and Merker grass.
Proper stocking rates and deferred grazing, as well as
liming and fertilizing, are chief management needs.
This soil is suited to Honduras pine, Eucalyptus
robusta, and mahoe trees. Production of Honduras pine is
moderate, about 1100 board feet per acre per year. The
hazard of erosion and limitations on the use of equipment
are the major concerns of management. Logging roads,
skid trails, and planting should be on the contour to help
control erosion. Brush removal, careful hand planting, and
fertilizing increase the survival of planted seedlings.
This soil is limited for most urban uses because it is
steep and shallow to rock. If the soil is used as construc-
tion sites, development should be on the contour. Removal
of vegetation should be held to a minimum, and tempora-
ry plant cover established quickly in denuded areas.
Capability subclass VIe.
PaF-Pandura sandy loam, 40 to 60 percent slopes.
This is a very steep, well drained soil on side slopes of
dissected uplands. Slopes are irregular and are 200 to 800
feet long. The areas range from 50 to 1000 acres. A few
shallow and deep gullies have formed.
Typically the surface layer is dark brown, friable sandy
loam about 7 inches thick. The subsoil is about 5 inches
thick; it is dark yellowish brown, friable sandy loam. The
substratum, beginning at a depth of 12 inches, is very
pale brown, pale brown, dark yellowish brown, and white
sandy loam saprolite.
Included with this soil in mapping are spots of Limones
and Jagueyes soils. Also included are few spots of rock
land. The surface layer of the Limones soils is dark yel-
lowish brown clay, and that of the Jagueyes soils is dark
yellowish brown loam. These soils make up 10 to 20 per-
cent of this mapping unit.
Permeability is moderate, and the available water
capacity is low. Runoff is rapid and erosion is a hazard.
Slippage is common in roadbanks, ditches, and
drainageways. This soil is difficult to work because it is
very steep. Hillside ditches and diversions are difficult to
lay out, establish, and maintain. The root zone is shallow.
Natural fertility is medium. Controlling erosion is the
major concern of management.
This soil has been in brush and brushy pasture most of
the time. It is suited to pangolagrass.


Proper stocking rates and deferred grazing, as well as
liming and fertilizing, are chief management needs.
This soil is suited to Honduras pine and Eucalyptus
robusta trees. Production of Honduras pine is low, about
900 board feet per acre per year. The hazard of erosion
and limitations on the use of equipment are the major
concerns of management. Logging roads, skid trails, and
planting should be on the contour to help control erosion.
Brush removal, careful hand planting, and fertilizing in-
crease the survival of planted seedlings.
This soil is limited for most urban uses because it is
very steep and shallow to rock. If the soil is used as con-
struction sites, development should be on the contour.
Removal of vegetation should be held to a minimum, and
temporary plant cover established quickly in denuded
areas. Capability subclass VIIe.
PeF-Pellejas clay loam, 40 to 60 percent slopes. This
is a very steep, well drained soil on short side slopes and
narrow ridges of the strongly dissected humid uplands.
Slopes are irregular and are 100 to 300 feet long. The
areas range from 20 to 200 acres. A few shallow and deep
gullies have formed.
Typically the surface layer is dark brown, friable clay
loam about 4 inches thick. The subsoil is about 12 inches
thick; it is yellowish brown clay loam. The substratum,
beginning at a depth of 16 inches, is pale brown, light yel-
lowish brown, gray, pinkish gray, and dark greenish gray
very friable sandy loam saprolite.
Included with this soil in mapping are spots of Lirios
soils. Also included are small areas that have slopes less
than 40 percent. The surface layer of the Lirios soils is
brown silty clay loam. These soils make up 10 to 20 per-
cent of this mapping unit.
Permeability is rapid, and the available water capacity
is low. Runoff is very rapid, and erosion is a hazard. Slip-
page is common in roadbanks, ditches, and drainageways.
This soil is difficult to work because it is very steep. Hill-
side ditches and diversions are difficult to lay out,
establish, and maintain. The root zone is deep. Natural
fertility is medium. Controlling erosion is the major con-
cern of management.
This soil has been in brush and brushy pasture. It is
suited to pangolagrass.
Proper stocking rates and deferred grazing, as well as
liming and fertilizing, are chief management needs.
This soil is suited to Honduras pine and Eucalyptus
robusta trees. Production of Honduras pine is low, about
900 board feet per acre per year. The hazard of erosion
and limitations on the use of equipment are the major
concerns of management. Logging roads, skid trails, and
planting should be on the contour to help control erosion.
The use of logging equipment is restricted at times
because the soil is soft and slippery when wet. Brush
removal, careful hand planting, and fertilizing increase
the survival of planted seedlings.
This soil is limited for most urban uses because it is
very steep and subject to landslides. If the soil is used as
construction sites, development should be on the contour.







SAN JUAN AREA, PUERTO RICO


Removal of vegetation should be held to a minimum, and
temporary plant cover established quickly in denuded
areas. Capability subclass VIIe.
Re-Reilly sandy loam. This is a nearly level, exces-
sively drained soil on river flood plains adjacent to
streams. The areas range from 10 to 100 acres.
Typically the surface layer is dark brown, very friable
sandy loam about 7 inches thick. The underlying material
is dark grayish brown gravelly sand to a depth of 18
inches and is coarse clean sand and gravel below 18
inches.
Included with this soil in mapping are spots of river-
wash consisting of large size gravel. The spots of river-
wash make up 10 to 20 percent of this mapping unit.
Permeability is rapid, and the available water capacity
is low. Runoff is slow. This soil is easily worked. The root
zone is shallow. Natural fertility is low.
This soil has been in brush and brushy pasture., It is
suited to pangolagrass and Merker grass.
Proper stocking rates and deferred grazing, as well as
liming and fertilizing, are chief management needs.
This soil is limited for most urban uses because of the
flood hazard and seepage. Capability subclass IVs.
RoB-Rio Arriba clay, 2 to 5 percent slopes. This is a
gently sloping, moderately well drained soil on alluvial
fans and terraces above the river flood plains. Slopes are
gently undulating and are 100 to 500 feet long. The areas
range from 15 to 400 acres.
Typically the surface layer is brown, firm clay about 8
inches thick. The subsoil from 8 to 28 inches is yellowish
brown, firm clay and from 28 to 60 inches is reddish yel-
low, firm clay. Below a depth of 16 inches, the subsoil is
mottled with yellowish red and red.
Included with this soil in mapping are small areas of
Mabi soils. The surface area of the Mabi soils is very dark
grayish brown clay. These soils make up 10 to 20 percent
of this mapping unit.
Permeability is moderately slow, and the available
water capacity is high. Runoff is medium, and erosion is a
hazard. This soil is difficult to work because of the sticki-
ness and plasticity of the clay. The root zone is deep.
Natural fertility is medium. Crops respond well to heavy
applications of lime and fertilizers. Controlling erosion is
the major concern of management.
This soil has been used for sugarcane. It is suited to
pangolagrass, improved bermudagrass, paragrass, and
bermudagrass.
Proper stocking rates and deferred grazing, as well as
liming and fertilizing, are chief management needs.
This soil is limited for most urban uses because of its
clayey nature, slow permeability, high shrink-swell poten-
tial, and the flood hazard. Capability subclass IIs.
RoC2-Rio Arriba clay, 5 to 12 percent slopes,
eroded. This is a sloping, moderately well drained soil on
alluvial fans and terraces above the river flood plains.
Slopes are undulating and are 100 to 500 feet long. The
areas range from 10 to 300 acres. This soil has lost much
of the surface layer through erosion.


Typically the surface layer is brown, firm clay about 8
inches thick. The subsoil from 8 to 28 inches is yellowish
brown, firm clay and from 28 to 60 inches is reddish yel-
low, firm clay. Below a depth of 16 inches, the subsoil is
mottled with yellowish red and red.
Included with this soil in mapping are small areas of
Juncos and Mabi soils. The surface area of the Juncos
soils is black clay, and that of the Mabi soils is very dark
grayish brown clay. These soils make up 10 to 20 percent
of this mapping unit.
Permeability is moderately slow, and the available
water capacity is high. Runoff is rapid, and erosion is a
hazard. This soil is difficult to work. The root zone is
deep. Natural fertility is medium. Crops respond well to
lime and fertilizers. Controlling erosion is the major con-
cern of management.
This soil has been used for sugarcane. It is suited to
pangolagrass, improved bermudagrass, paragrass, and
bermudagrass.
Proper stocking rates and deferred grazing, as well as
liming and fertilizing, are chief management needs.
This soil is limited for most urban uses because of its
clayey nature, slow permeability, high shrink-swell poten-
tial, and the flood hazard. Capability subclass IIIe.
RpD2-Rio Piedras clay, 12 to 20 percent slopes,
eroded. This is a moderately steep, well drained soil on
foot slopes and side slopes of dissected uplands. Slopes
are irregular and are 100 to 300 feet long. The areas
range from 10 to 300 acres. This soil has lost most of its
original surface layer through erosion. A few shallow and
deep gullies have formed.
Typically the surface layer is dark brown, firm clay
about 8 inches thick. The subsoil is about 20 inches thick;
it is red, very firm clay with yellowish brown, red, and
brownish yellow mottles. The substratum, beginning at a
depth of 28 inches, is mixed red and brownish yellow clay
saprolite with strong brown and light gray mottles. Ce-
mented shale bedrock is at a depth of 48 inches.
Included with this soil in mapping are spots of Yunes
soils. The surface layer of the Yunes soils is dark reddish
brown silty clay loam. These soils make up 10 to 20 per-
cent of this mapping unit.
Permeability is moderately slow, and the available
water capacity is moderate. Runoff is medium, and ero-
sion is a hazard. Slippage is common in roadbanks,
ditches, and drainageways. This soil is difficult to work
because it is moderately steep and because of the sticki-
ness and plasticity of the clay. Hillside ditches and diver-
sions are difficult to lay out, establish, and maintain. The
root zone is deep. Natural fertility is low. Crops respond
well to heavy applications of lime and fertilizers. Con-
trolling erosion is the major concern of management.
This soil has been used for plantains. It is suited to
pangolagrass and Merker grass.
Proper stocking rates and deferred grazing, as well as
liming and fertilizing, are chief management needs.
This soil is suited to Honduras pine, Honduras
mahogany, kadam, mahoe, and Eucalyptus robusta trees.







SOIL SURVEY


Production of Honduras pine is moderate, about 1300
board feet per acre per year. The hazard of erosion and
limitations on the use of equipment are the major con-
cerns of management. Logging roads, skid trails, and
planting should be on the contour to help control erosion.
The use of logging equipment is restricted at times
because the soil if soft and slippery when wet. Brush
removal, careful hand planting, and fertilizing increase
the survival of planted seedlings.
This soil is limited for most urban uses because it is
moderately steep and subject to landslides. If the soil is
used as construction sites, development should be on the
contour. Removal of vegetation should be held to a
minimum, and temporary plant cover established quickly
in denuded areas. Capability subclass IVe.
RpE2-Rio Piedras clay, 20 to 40 percent slopes,
eroded. This is a steep, well drained soil on side slopes of
dissected uplands. Slopes are irregular and are 100 to 200
feet long. The areas range from 20 to 200 acres. This soil
has lost most of its original surface layer through erosion.
A few shallow and deep gullies have formed.
Typically the surface layer is dark brown, firm clay
about 8 inches thick. The subsoil is about 20 inches thick;
it is red, very firm clay with yellowish brown, red, and
brownish yellow mottles. The substratum, beginning at a
depth of 28 inches, is mixed red and brownish yellow clay
saprolite with strong brown and light gray mottles. Ce-
mented shale bedrock is at a depth of 48 inches.
Included with this soil in mapping are spots of Yunes
soils. The surface layer of the Yunes soils is dark reddish
brown silty clay loam. These soils make up about 10 to 20
percent of this mapping unit.
Permeability is moderately slow, and the available
water capacity is moderate. Runoff is rapid, and erosion
is a hazard. Slippage is common in roadbanks, ditches, and
drainageways. This soil is difficult to work because it is
steep and because of the stickiness and plasticity of the
clay. Hillside ditches and diversions are difficult to lay
out, establish, and maintain. The root zone is deep. Natu-
ral fertility is low. Controlling erosion is the major con-
cern of management.
This soil has been in brush and brushy pasture most of
the time. It is suited to pangolagrass and Merker grass.
Proper stocking rates and deferred grazing, as well as
liming and fertilizing, are chief management needs.
This soil is suited to Honduras pine and Eucalyptus
robusta trees. Production of Honduras pine is moderate,
about 1100 board feet per acre per year. The hazard of
erosion and limitations on the use of equipment are the
major concerns of management. Logging roads, skid
trails, and planting should be on the contour to help con-
trol erosion. The use of logging equipment is restricted at
times because the soil is soft and slippery when wet.
Brush removal, careful hand planting, and fertilizing in-
crease the survival of planted seedlings.
This soil is limited for most urban uses because it is
steep and subject to landslides. If the soil is used as con-
struction sites, development should be on the contour.


Removal of vegetation should be held to a minimum, and
temporary plant cover established quickly in denuded
areas. Capability subclass Vie.
RpF2-Rio Piedras clay, 40 to 60 percent slopes,
eroded. This a very steep, well drained soil on side slopes
of dissected uplands. Slopes are irregular and are 100 to
300 feet long. The areas range from 50 to 400 acres. This
soil has lost most of its original surface layer through ero-
sion. A few shallow and deep gullies have formed.
Typically the surface layer is dark brown, firm clay
about 8 inches thick. The subsoil is about 20 inches thick;
it is red, very firm clay with red, brownish yellow, and
yellowish brown mottles. The substratum, beginning at a
depth of 28 inches, is mixed red and brownish yellow clay
saprolite with strong brown and light gray mottles.
Included with this soil in mapping are a few spots of
Yunes soils. Also included are severely eroded spots on
tops of ridges and along drains where the substratum is
exposed. The surface layer of the Yunes soils is dark red-
dish brown, silty clay loam. These soils make up 10 to 20
percent of this mapping unit.
Permeability is moderately slow, and the available
water capacity is moderate. Runoff is rapid, and erosion
is a hazard. Slippage is common in roadbanks, ditches, and
drainageways. This soil is difficult to work because it is
very steep and because of the stickiness and plasticity of
the clay. Hillside ditches and diversions are difficult to
lay out, establish, and maintain. The root zone is deep.
Natural fertility is low. Controlling erosion is the major
concern of management.
This soil has been in brush and brushy pasture most of
the time. It is suited to pangolagrass.
Proper stocking rates and deferred grazing, as well as
liming and fertilizing, are chief management needs.
This soil is suited to Honduras pine and Eucalyptus
robusta trees. Production of Honduras pine is moderate,
about 1100 board feet per acre per year. The hazard of
erosion and limitations on the use of equipment are the
major concerns of management. Logging roads, skid
trails, and planting should be on the contour to help con-
trol erosion. The use of logging equipment is restricted at
times because the soil is soft and slippery when wet.
Brush removal, careful hand planting, and fertilizing in-
crease the survival of planted seedlings.
This soil is limited for most urban uses because it is
very steep, and subject to landslides. If the soil is used as
construction sites, development should be on the contour.
Removal of vegetation should be held to a minimum, and
temporary plant cover established quickly in denuded
areas. Capability subclass VIIe.
SaF-Sabana silty clay loam, 40 to 60 percent slopes.
This is a very steep, well drained soil on side slopes and
tops of humid volcanic uplands. Slopes are irregular and
are 100 to 800 feet long. The areas range from 20 to 300
acres. A few shallow and deep gullies have formed.
Typically the surface layer is very dark grayish brown,
firm silty clay loam about 3 inches thick. The subsoil is
about 12 inches thick; it is dark brown, friable silty clay







SAN JUAN AREA, PUERTO RICO


in the upper part and variegated light brownish gray and
strong brown, firm clay in the lower part. Consolidated
volcanic rock is at a depth of 15 inches.
Included with this soil in mapping are spots of Mucara
and Caguabo soils. Also included are some ridges with
boulders and stones on the surface. The surface layer of
the Mucara soils is very dark grayish brown clay, and
that of the Caguabo soils is dark grayish brown clay loam.
These soils make up 10 to 20 percent of this mapping
unit.
Permeability is moderate, and the available water
capacity is low. Runoff is rapid, and erosion is a hazard.
Slippage is common in roadbanks, ditches, and
drainageways. This soil is difficult to work because it is
very steep. Hillside ditches and diversions are difficult to
lay out, establish, and maintain. The root zone is shallow.
Natural fertility is medium. Controlling erosion is the
major concern of management.
This soil has been in brush and brushy pasture most of
the time. It is suited to pangolagrass.
Proper stocking rates and deferred grazing, as well as
liming and fertilizing, are chief management needs.
This soil is suited to Honduras pine and Eucalyptus
robusta trees. Production of Honduras pine is very low,
about 700 board feet per acre per year. The hazard of
erosion and limitations on the use of equipment are the
major concerns of management. Logging roads, skid
trails, and planting should be on the contour to help con-
trol erosion. The use of logging equipment is restricted at
times because the soil is soft and slippery when wet.
Brush removal, careful hand planting, and fertilizing in-
crease the survival of planted seedlings.
This soil is limited for most urban uses because it is
very steep and subject to landslides. If the soil is used as
construction sites, development should be on the contour.
Removal of vegetation should be held to a minimum, and
temporary plant cover established quickly in denuded
areas. Capability subclass VIIs.
ScB-Sabana Seca clay, 2 to 8 percent slopes. This is
a gently sloping, poorly drained soil on coastal plains. The
areas range from 10 to 200 acres.
Typically the surface layer is very dark grayish brown,
firm clay about 10 inches thick. The clay subsoil is highly
mottled. The dominant color from 10 to 13 inches is dark
grayish brown, from 13 to 36 inches is light gray, and
from 36 to 70 inches is white. The mottles are yellowish
brown, red, dark red, dusky red, and strong brown.
Included with this soil in mapping are spots of Al-
mirante soils. The surface layer of the Almirante soils is
dark yellowish brown clay. These soils make up 10 to 20
percent of this mapping unit.
Permeability is very slow, and the available water
capacity is high. Runoff is very slow. This soil is very dif-
ficult to work because of wetness and because of the
stickiness and plasticity of the clay. The root zone is shal-
low. Natural fertility is low.
This soil has been in brush and brushy pasture most of
the time. It is suited to pangolagrass, common bermu-
dagrass, paragrass, and Merker grass.


Proper stocking rates and deferred grazing, as well as
liming and fertilizing, are chief management needs.
This soil is limited for most urban uses because it is
wet and clayey. Capability subclass IIIw.
Sm-Saladar muck. This is a level, very poorly
drained soil in closed depressions and in coastal marshes
with inadequate outlets. The areas range from 10 to 700
acres.
Typically the surface layer is black muck about 10
inches thick. The underlying layers to a depth of 51
inches or more are black muck.
Included with this soil are spots of Martin Pena soils.
The surface layer of the Martin Pena soils is black muck
about 8 inches thick that overlies clayey material. These
soils make up about 10 to 20 percent of this mapping unit.
Permeability is slow, and the available water capacity is
high. Runoff is slow. This soil is difficult to work because
it is too wet. Reclamation projects of this soil would be
difficult and costly.
This soil has been in cattails, sedges, and reeds most of
the time.
This soil is limited for most urban uses because it is too
wet and is subject to overflow. Capability subclass VIIIw.
SoE-Soller clay loam, 20 to 40 percent slopes. This
is a steep, well drained soil on side slopes and hilltops of
rounded limestone hills. Slopes are convex, and are 100 to
300 feet long. The areas range from 20 to 100 acres.
Typically the surface layer is very dark grayish brown,
friable clay loam about 5 inches thick. The subsoil is about
7 inches thick; it is dark brown, firm clay. The sub-
stratum, beginning at a depth of 12 inches, is yellow, fria-
ble, weathered limestone. Hard limestone is at a depth of
24 inches.
Included with this soil in mapping are spots of Colinas
soils. Also included are severely eroded small areas on
hilltops and along drainageways where the hard fragmen-
tal limestone parent material is exposed. The surface
layer of the Colinas soils is dark brown clay loam. These
soils make up 10 to 20 percent of this mapping unit.
Permeability is moderate, and the available water
capacity is low. Runoff is rapid, and erosion is a hazard.
Slippage is common in roadbanks, ditches, and
drainageways. This soil is difficult to work because it is
steep. Hillside ditches and diversions are difficult to lay
out, establish, and maintain. The root zone is shallow.
Natural fertility is low. Controlling erosion is the major
concern of management.
This soil has been in brush and brushy pasture most of
the time. It is suited to pangolagrass.
Proper stocking rates and deferred grazing, as well as
fertilizing, are chief management needs.
This soil is suited to Honduras mahogany. Production of
Honduras mahogany is low, about 350 board feet per acre
per year. The hazard of erosion and limitations in the use
of equipment are the major concerns of management.
Logging roads, skid trails, and planting should be on the
contour to help control erosion. The use of logging equip-
ment is restricted at times because the soil is soft and






SOIL SURVEY


slippery when wet. Brush removal, careful hand planting,
and fertilizing increase the survival of planted seedlings.
This soil is limited for most urban uses because it is
steep and shallow to bedrock. If this soil is used as con-
struction sites, development should be on the contour.
Removal of vegetation should be held to a minimum, and
temporary plant cover established quickly in denuded
areas. Capability subclass VIIe.
SoF-Soller clay loam, 40 to 60 percent slopes. This
is a very steep, well drained soil on side slopes and hill-
tops of rounded limestone hills. Slopes are convex and are
100 to 200 feet long. The areas range from 30 to 500
acres.
Typically the surface layer is very dark grayish brown,
friable clay loam about 5 inches thick. The subsoil is about
7 inches thick; it is dark brown, firm clay. The sub-
stratum, beginning at a depth of 12 inches, is yellow, fria-
ble, weathered limestone. Hard limestone bedrock is at a
depth of 24 inches.
Included with this soil in mapping are small areas of
Colinas soils. Also included are some severely eroded
spots on hilltops and along drainageways where the hard
fragmental limestone parent material is exposed. The sur-
face layer of the Colinas soils is dark brown clay loam.
These soils make up 10 to 20 percent of this mapping
unit.
Permeability is moderate, and the available water
capacity is low. Runoff is very rapid, and erosion is a
hazard. Slippage is common in roadbanks, ditches, and
drainageways. This soil is difficult to work because it is
very steep. Hillside ditches and diversions are difficult to
lay out, establish, and maintain The root zone is shallow.
Natural fertility is low. Controlling erosion is the major
concern of management.
This soil has been in brush and brushy pasture most of
the time. It is suited to pangolagrass.
Proper stocking rates and deferred grazing, as well as
fertilizing, are chief management needs.
This soil is suited to Honduras mahogany. Production of
Honduras mahogany is very low, less than 250 board feet
per acre per year. The hazard of erosion and limitations
in the use of equipment are the major concerns of
management. Logging roads, skid trails, and planting
should be on the contour to help control erosion. The use
of logging equipment is restricted at times because the
soil is soft and slippery when wet. Brush removal, careful
hand planting, and fertilizing increase the survival of
planted seedlings.
This soil is limited for most urban uses because it is
very steep and shallow to bedrock. If this soil is used as
construction sites, development should be on the contour.
Removal of vegetation should be held to a minimum, and
temporary plant cover established quickly in denuded
areas. Capability subclass VIIe.
TaF-Tanama-Rock outcrop complex, 20 to 60 per-
cent slopes. This complex consists of steep to very steep,
shallow, well drained Tanama soils and Rock outcrop. This
complex has formed in karst topography characterized by


pepino hills or haystack hills in the northern part of the
survey area. The topography is very rugged, and slopes in
many directions. This irregular topography is caused by
the solutional destruction of the dense, thin bedded
limestone. Most areas are asymmetrical in form and range
from 25 to 300 feet in height. They are about 5 to 100
acres. This complex is about 45 percent Tanama soils, 40
percent Rock outcrop, and 15 percent minor soils.
Tanama soils and Rock outcrop form such an intricate
pattern that it was not practical to separate them in
mapping. In a representative profile of Tanama soils the
surface layer is dark reddish brown, friable clay about 4
inches thick. The subsoil is about 10 inches thick; it is red-
dish brown, firm clay. Hard semiconsolidated limestone is
at a depth of 14 inches.
Included with this complex in mapping are spots of
Soller soils. Also included are small areas of miscellaneous
soils that have formed between the limestone outcrops
and in the crevices and holes formed in the limestone.
The surface layer of the Soller soils is very dark grayish
brown clay loam.
In the Tanama soils the permeability is moderate and
the available water capacity is low. Runoff is rapid, and
erosion is a hazard. This soil is difficult to work because it
is steep to very steep, and because it is intermingled with
Rock outcrop. The root zone is shallow. Natural fertility
is low. Most of this complex is in brush.
This complex is limited for most urban uses mainly
because of the slopes, rock outcrops, and shallow depth to
rock. Capability subclass VIIs.
To-Toa silty clay loam. This is a nearly level,
moderately well drained to well drained soil on flood
plains (fig. 10). The areas range from 20 to 500 acres.
Typically the surface layer is dark brown, friable silty
clay loam about 8 inches thick. The subsoil is about 8
inches thick; it is dark brown, friable silty clay loam with
pale brown mottles. The substratum, beginning at a depth
of 16 inches, is brown and dark brown, friable silty clay
loam with dark reddish brown, light gray, and brown mot-
tles.
Included with this soil in mapping are spots of Dique,
Coloso, and Bajura soils. The surface layer of the Dique
soils is dark brown loam; that of the Coloso soils is dark
brown silty clay loam; and that of the Bajura soils is dark
brown clay. These soils make up 10 to 20 percent of this
mapping unit.
Permeability and the available water capacity are
moderate. This soil is easy to work. The root zone is deep.
Natural fertility is high. Crops respond well to applica-
tions of lime and fertilizers.
This soil has been used for sugarcane. It is suited to
pangolagrass and Merker grass.
Proper stocking rates and deferred grazing, as well as
liming and fertilizing, are chief management needs.
This soil is limited for most urban uses because of the
flood hazard, its clayey nature, and low strength. Capa-
bility class I.







SAN JUAN AREA, PUERTO RICO


TrB-Torres loamy sand, 2 to 5 percent slopes. This
is a gently sloping, excessively drained soil on coastal
plains and in trapped valleys among the haystack hills.
Slopes are gently undulating and are 50 to 200 feet long.
The areas range from 5 to 200 acres.
Typically the surface layer is very dark grayish brown
and dark brown, loose loamy sand about 28 inches thick.
The subsoil, to a depth of 64 inches, is yellowish brown,
firm clay with prominent red, dark red, and light gray
mottles.
Included with this soil in mapping are spots of Matan-
zas and Almirante soils. The surface layer of the Matan-
zas soils is dark reddish brown clay, and that of the Al-
mirante soils is strong brown clay. These soils make up 10
to 20 percent of this mapping unit.
Permeability is rapid in the surface layer and moderate
in the subsoil. The available water capacity is low. Runoff
is slow. This soil is easily worked. The root zone is deep.
Natural fertility is low.
This soil has been in brush and brushy pasture most of
the time. It is suited to pangolagrass, improved bermu-
dagrass, and Merker grass.
Proper stocking rates and deferred grazing, as well as
liming and fertilizing, are chief management needs.
This soil is suitable for most urban uses. It has limita-
tions for some uses because of the clayey subsoil. Capa-
bility subclass VIs.
Ts-Tropopsamments. Tropopsamments consist of
nearly level, deep, excessively drained soils formed in a
thick accumulation of finely ground sea shells and sand.
The areas are narrow strips of land that parallel the
coast.
Commonly the soils to a depth of 60 inches are pale yel-
low or yellow, loose sand containing many shells and shell
fragments.
Most areas of these soils are devoid of vegetation or
they are producing a few coconuts.
These soils are limited for most urban uses because
they are subject to the wave action of the sea. Capability
subclass VIIIs.
Ud-Urban land-Durados complex. This nearly level
complex is about 70 percent Urban land, 20 percent Du-
rados soils, and about 10 percent other soils. The areas
range from 500 to 2000 acres. The composition of this unit
is about the same from place to place.
In undisturbed areas the surface layer of the Durados
soils is very dark grayish brown, very friable sandy loam
about 14 inches thick. The underlying material from 14 to
23 inches is very dark grayish brown, loose loamy sand;
from 23 to 38 inches is very pale brown and very dark
grayish brown loose sand; and from 38 to 60 inches is
mixed dark yellowish brown, black, brownish yellow, and
yellowish brown, loose sand with thick layers of cemented
sand. Urban land consists mainly of sites for houses, in-
dustrial buildings, parking lots, streets, and other struc-
tures that accompany community development. The land-
scape has been altered in places by cutting, filling, or
grading and shaping. It was not practical to map the soils


separately because they were so intricately intermingled
with Urban land.
Mapped areas of this complex are only in the populated
and industrial areas in the vicinity of Levittown. Capabili-
ty subclass not assigned.
Uni-Urban land-Mucara complex. This complex is
about 50 percent Urban land, 30 percent Mucara soils, and
about 20 percent Rock outcrop and other soils. Slopes are
irregular and are 100 to 300 feet long. The areas range
from 500 to 1000 acres.
Typically the surface layer of the Mucara soils is very
dark grayish brown, firm clay about 5 inches thick. The
subsoil is about 7 inches thick; it is dark brown, firm clay.
The substratum, beginning at a depth of 12 inches, is
highly weathered volcanic rock. Hard volcanic rock is at a
depth of 30 inches. Urban land consists of areas that have
been altered to prepare building sites, create trafficways,
or create a better environment for growing lawn grasses
and landscape plants.
Included with this complex are Rock outcrop and other
minor soils. These make up about 20 percent of this
mapping unit. It was not practical to map the soils
separately because they were so intricately intermingled
with Urban land.
Mapped areas of this complex are only in the populated
and industrial areas around cities. Capability subclass not
assigned.
Us-Urban land-Sabana Seca complex. This complex
is about 60 percent Urban land, 30 percent Sabana Seca
soils, and 10 percent other soils. The areas are nearly
level to gently sloping and are on coastal plains. They
range from. 1000 to 3000 acres. The composition of this
complex is about the same from place to place.
In undisturbed areas the surface layer of the Sabana
Seca soils is very dark grayish brown, firm clay about 10
inches thick. The clay subsoil is highly mottled. The domi-
nant color from 10 to 13 inches is dark grayish brown;
from 13 to 36 inches is light gray; and from 36 to 70
inches is white. The mottles are yellowish brown, red,
dark red, dusky red, and strong brown. Urban land con-
sists mainly of sites for houses, industrial buildings, park-
ing lots, streets, and other structures that accompany
community development. The landscape has been altered
in places by cutting, filling, and shaping. It was not prac-
tical to map the soils separately because they were so in-
tricately intermingled with Urban land.
Mapped areas of this complex are only in the populated
areas in the vicinity of Levittown. Capability subclass not
assigned.
Uv-Urban land-Vega Alta complex. This complex is
about 60 percent Urban land, 25 percent Vega Alta soils,
and 15 percent Aceitunas and Humatas soils. The areas
are gently undulating to moderately undulating. They
range from 3000 to 5000 acres. The composition of the
complex is about the same from place to place.
In undisturbed areas the Vega Alta soils have a surface
layer of dark yellowish brown, friable clay loam about 8
inches thick. The subsoil from 8 inches to a depth of 52







SOIL SURVEY


inches is mainly red, strong brown, brownish yellow, and
dark red clay. From 52 inches to a depth of 84 inches, the
subsoil is dark red, brownish yellow, and light gray, fria-
ble clay. Urban land consists mainly of sites for houses,
industrial buildings, parking lots, streets, and other struc-
tures that accompany development. The landscape has
been altered in places by cutting, filling, or grading and
shaping. It was not practical to map the soils separately
because they were so intricately intermingled with Urban
land.
Mapped areas of this complex are only in the populated
and industrial areas in the vicinities of the San Juan
metropolitan area, Bayamon, and other towns and commu-
nities. Capability subclass not assigned.
VaB-Vega Alta clay loam, 2 to 5 percent slopes.
This is a gently sloping, well drained soil on coastal plains
and terraces. Slopes are undulating and are 100 to 200
feet long. The areas range from 10 to 100 acres.
Typically the surface layer is dark yellowish brown, fri-
able clay loam about 8 inches thick. The subsoil from 8
inches to a depth of 52 inches is mainly red, strong
brown, brownish yellow, and dark red clay. From 52
inches to a depth of 84 inches, the subsoil is dark red,
brownish yellow, and light gray, friable clay.
Included with this soil in mapping are spots of Al-
mirante soils. The surface layer of the Almirante soils is
dark yellowish brown clay. These soils make up 10 to 20
percent of this mapping unit.
Permeability and the available water capacity are
moderate. Runoff is medium, and erosion is a hazard. This
soil is difficult to work because of the stickiness and
plasticity of the clay. The root zone is deep. Natural fer-
tility is medium. Crops respond well to heavy applications
of lime and fertilizers. Controlling erosion is the major
concern of management.
This soil has been used for sugarcane. It is suited to
pangolagrass, improved bermudagrass, paragrass, and
Merker grass.
Proper stocking rates and deferred grazing, as well as
liming and fertilizing, are chief management needs.
This soil has moderate limitations for most urban uses
because of its clayey nature and low strength. If the soil
is used as construction sites, development should be on
the contour. Removal of vegetation should be held to a
minimum, and temporary plant cover established quickly
in denuded areas. Capability subclass IIe.
VaC2-Vega Alta clay loam, 5 to 12 percent slopes,
eroded. This is a sloping, well drained soil on coastal
plains and terraces (fig. 11). Slopes are undulating and are
100 to 300 feet long. The areas range from 20 to 300
acres. This soil has lost much of its original surface layer
through erosion.
Typically the surface layer is dark yellowish brown, fri-
able clay loam about 8 inches thick. The subsoil from 8
inches to a depth of 52 inches is mainly red, strong
brown, brownish yellow, and dark red clay. From 52
inches to a depth of 84 inches, the subsoil is dark red,
brownish yellow, and light gray friable clay.


Included with this soil in mapping are spots of Al-
mirante soils. The surface layer of the Almirante soils is
dark yellowish brown clay. These soils make up 10 to 20
percent of this mapping unit.
Permeability and the available water capacity are
moderate. Runoff is medium, and erosion is a hazard. This
soil is difficult to work because of the stickiness and
plasticity of the clay. The root zone is deep. Natural fer-
tility is medium. Crops respond well to heavy applications
of lime and fertilizers. Controlling erosion is the major
concern of management.
This soil has been used for sugarcane. It is suited to
pangolagrass, improved bermudagrass, paragrass, and
Merker grass.
Proper stocking rates and deferred grazing, as well as
liming and fertilizing, are chief management needs.
This soil is moderately limited for most urban uses
because it is sloping and clayey and has low strength. If
the soil is used as construction sites, development should
be on the contour. Removal of vegetation should be held
to a minimum, and temporary plant cover established
quickly in denuded areas. Capability subclass IIIe.
Vg-Vega Baja silty clay. This is a nearly level,
somewhat poorly drained soil on coastal plains and alluvi-
al fans. The areas range from 50 to 100 acres.
Typically the surface layer is dark brown, dark grayish
brown, and yellowish brown, firm silty clay to a depth of
12 inches. The subsoil from 12 to 17 inches is dark grayish
brown and yellowish brown, firm silty clay; from 17 to 32
inches is mixed strong brown and gray clay; and from 32
to 50 inches is brownish yellow and gray silty clay loam.
The substratum, beginning at a depth of 50 inches, is light
gray and strong brown, firm clay.
Included with this soil in mapping are spots of Coloso
soils. The surface layer of the Coloso soils is dark brown
silty clay loam. These soils make up 10 to 20 percent of
this mapping unit.
Permeability is slow, and the available water capacity is
high. This soil is difficult to work because of wetness and
because of the stickiness and plasticity of the clay. The
root zone is deep. Natural fertility is medium. Crops
respond well to heavy applications of lime and fertilizers.
This soil has been used for sugarcane.
This soil is limited for most urban uses because of the
flood hazard, wetness, slow permeability, and its clayey
nature. Capability subclass IIw.
VkC2-Via clay loam, 5 to 12 percent slopes, eroded.
This is a sloping, well drained soil on high stream ter-
races. Slopes are undulating and are 100 to 200 feet long.
The areas range from 10 to 100 acres. This soil has lost
much of its original surface layer through erosion.
Typically the surface layer is dark brown, friable clay
loam about 9 inches thick. The subsoil is about 27 inches
thick; it is strong brown and yellowish brown, firm clay
loam. The substratum, beginning at a depth of 36 inches,
is strong brown, firm very gravelly clay loam.
Included with this soil in mapping are spots of Rio Ar-
riba and Mabi soils. The surface layer of the Mabi soils is







SAN JUAN AREA, PUERTO RICO


very dark grayish brown clay, and that of the Rio Arriba
soils is brown clay. These soils make up 10 to 20 percent
of this mapping unit.
Permeability and the available water capacity are
moderate. Runoff is medium, and erosion is a hazard. This
soil is difficult to work because of the stickiness and
plasticity of the clay. The root zone is deep. Natural fer-
tility is medium. Crops respond well to heavy applications
of lime and fertilizers. Controlling erosion is the major
concern of management.
This soil has been used for crops such as sugarcane. It
is suited to pangolagrass and Merker grass.
Proper stocking rates and deferred grazing, as well as
liming and fertilizing, are chief management needs.
This soil has moderate to severe limitations for most
urban uses because of slope, seepage, and its clayey na-
ture. If the soil is used as construction sites, development
should be on the contour. Removal of vegetation should
be held to a minimum, and temporary plant cover
established quickly in denuded areas. Capability subclass
IIIe.
Vv-Vivi loam. This is a nearly level, somewhat exces-
sively drained soil on river flood plains. The areas range
from 10 to 100 acres.
Typically the surface layer of this soil is dark brown,
very friable loam about 9 inches thick. The subsoil is
about 13 inches thick; it is dark yellowish brown, friable
loam. The substratum, beginning at a depth of 22 inches,
is dark yellowish brown loam from 22 inches to 34 inches,
yellowish brown, very friable very fine sandy loam from
34 to 47 inches, and yellowish brown loamy sand from 47
to 58 inches.
Included with this soil in mapping are spots of Reilly
soils. The surface layer of the Reilly soils is dark brown
sandy loam. These soils make up 10 to 20 percent of the
areas of this mapping unit.
Permeability is rapid, and the available water capacity
is low. This soil is fertile and is easily worked. The root
zone is deep. Crops respond well to heavy applications of
lime and fertilizers and to irrigation.
This soil has been used for sugarcane.
This soil is limited for most urban uses because of the
flood hazard and seepage. Capability subclass IIs.
YeE-Yunes silty clay loam, 20 to 40 percent slopes.
This is a steep, well drained soil on side slopes of strongly
dissected uplands. The slopes are irregular and are 100 to
300 feet long. The areas range from 20 to 300 acres. A
few shallow and deep gullies have formed.
Typically the surface layer is dark reddish brown, fria-
ble silty clay loam about 2 inches thick. The subsoil is
about 14 inches thick; it is dark brown and brown, friable
very shaly silty clay loam. Below a depth of 16 inches is
bedded fragmental shale. The beds are 1 to 4 inches thick.
The shale is light red, strong brown, and pink.
Included with this soil in mapping are spots of Rio
Piedras soils. The surface layer of the Rio Piedras soils is
dark brown clay. These soils make up 10 to 20 percent of
this mapping unit.


Permeability is moderate, and the available water
capacity is low. Runoff is rapid, and erosion is a hazard.
Slippage is common in roadbanks, ditches, and
drainageways. This soil is not suited to cultivated crops
because it is steep and shallow to bedded shale. Con-
trolling erosion is the major concern of management.
This soil has been in brush and brushy pasture most of
the time. It is suited to pangolagrass.
Proper stocking rates and deferred grazing, as well as
liming and fertilizing, are chief management needs.
This soil is suited to Honduras pine and Eucalyptus
robusta trees. Production of Honduras pine is very low,
about 700 board feet per acre per year. The hazard of
erosion and limitations on the use of equipment are the
major concerns of management. Logging roads, skid
trails, and planting should be on the contour to help con-
trol erosion. The use of logging equipment is restricted at
times because the soils are slippery when wet. Brush
removal, careful hand planting, and fertilizing increase
the survival of seedlings.
This soil is limited for most urban uses because it is
steep and subject to landslides. If the soil is used for con-
struction sites, development should be on the contour.
Removal of vegetation should be held to a minimum, and
temporary plant cover established quickly in denuded
areas. Capability subclass VIIs.
YeF-Yunes silty clay loam, 40 to 60 percent slopes.
This is a very steep, well drained soil on side slopes of
strongly dissected uplands. The slopes are irregular and
are 100 to 300 feet long. The areas range from 30 to 250
acres. A few shallow and deep gullies have formed.
Typically the surface layer is dark reddish brown, fria-
ble silty clay loam about 2 inches thick. The subsoil is
about 14 inches thick; it is dark brown and brown, friable
very shaly silty clay loam. Below a depth of 16 inches is
bedded fragmental shale. The beds are 1 to 4 inches thick.
The shale is light red, strong brown, and pink.
Included with this soil in mapping are spots of Yunes
soils with less than 40 percent slopes. Also included are a
few small areas on tops of hills and along drainageways
where the bedded shale is exposed. These soils and areas
of shale make up 10 to 20 percent of this mapping unit.
Permeability is moderate, and the available water
capacity is low. Runoff is rapid, and erosion is a hazard.
Slippage is common in roadbanks, ditches, and
drainageways. This soil is not suited to cultivated crops
because it is very steep and shallow to bedded shale. Con-
trolling erosion is the major concern of management.
This soil has been in brush and brushy pasture most of
the time. It is suited to pangolagrass.
Proper stocking rates and deferred grazing, as well as
liming and fertilizing, are chief management needs.
This soil is suited to Honduras pine and Eucalyptus
robusta trees. Production of Honduras pine is low, about
700 board feet per acre per year. The hazard of erosion
and limitations on the use of equipment are the major
concerns of management. Logging roads, skid trails, and
planting should be on the contour to help control erosion.







SOIL SURVEY


The use of logging equipment is restricted at times
because the soils are slippery when wet. Brush removal,
careful hand planting, and fertilizing increase the survival
of seedlings.
This soil is limited for most urban uses because it is
very steep and subject to landslides. If the soil is used for
construction sites, development should be on the contour.
Removal of vegetation should be held to a minimum, and
temporary plant cover established quickly in denuded
areas. Capability subclass VIIs.


Use and management of the soils
The soil survey is a detailed inventory and evaluation
of the most basic resource of the survey area-the soil. It
is useful in adjusting land use, including urbanization, to
the limitations and potentials of natural resources and the
environment. Also, it can help avoid soil-related failures
in uses of the land.
While a soil survey is in progress, soil scientists, con-
servationists, engineers, and others keep extensive notes
about the nature of the soils and about unique aspects of
behavior of the soils. These notes include data on erosion,
drought damage to specific crops, yield estimates, flood-
ing, the functioning of septic tank disposal systems, and
other factors affecting the productivity, potential, and
limitations of the soils under various uses and manage-
ment. In this way, field experience and measured data on
soil properties and performance are used as a basis for
predicting soil behavior.
Information in this section is useful in planning use and
management of soils for crops, pasture, and woodland and
as sites for buildings, highways and other transportation
systems, sanitary facilities, and parks and other recrea-
tion facilities. From the data presented, the potential of
each soil for specified land uses can be determined, soil
limitations to these land uses can be identified, and costly
failures in houses and other structures, caused by un-
favorable soil properties, can be avoided. A site where
soil properties are favorable can be selected, or practices
that will overcome the soil limitations can be planned.
Planners and others using the soil survey can evaluate
the impact of specific land uses on the overall productivi-
ty of the survey area or other broad planning area and on
the environment. Productivity and the environment are
closely related to the nature of the soil. Plans should
maintain or create a land-use pattern in harmony with the
natural soil.
Contractors can find information that is useful in locat-
ing sources of sand and gravel, roadfill, and topsoil. Other
information indicates the presence of bedrock, wetness, or
very firm soil horizons that cause difficulty in excavation.
Health officials, highway officials, engineers, and many
other specialists also can find useful information in this
soil survey. The safe disposal of wastes, for example, is
closely related to properties of the soil. Pavements, side-
walks, campsites, playgrounds, lawns, and trees and
shrubs are influenced by the nature of the soil.


Crops and pasture
The major management concerns in the use of the soils
for crops and pasture are described in this section. In ad-
dition, the crops or pasture plants best suited to the soil,
including some not commonly grown in the survey area,
are discussed; the system of land capability classification
used by the Soil Conservation Service is explained; and
the estimated yields of the main crops and hay and
pasture plants are presented for each soil.
This section provides information about the overall
agricultural potential of the survey area and about the
management practices that are needed. The information is
useful to equipment dealers, land improvement contrac-
tors, fertilizer companies, processing companies, planners,
conservationists, and others. For each kind of soil, infor-
mation about management is presented in the section
"Soil maps for detailed planning." Planners of manage-
ment systems for individual fields or farms should also
consider the detailed information given in the description
of each soil.
More than 300,000 acres in the survey area was used
for crops and pasture in 1967, according to the Conserva-
tion Needs Inventory. Of this total, more than 89,000
acres was in crops and almost 211,000 acres in pasture.
The potential of the soils of the San Juan Area for in-
creased production of food is good. There is considerable
reserve productive capacity that is not being used for
crops or pasture at the present time. This potential
productive capacity could be further increased by extend-
ing the latest crop production technology to all land suita-
ble for cropland in the survey area. This soil survey can
greatly facilitate the application of such technology.
Acreage in crops and pasture has gradually been
decreasing as more land is used for urban development.
This is especially true in the urban fringe areas near the
San Juan metropolitan area. The use of this soil survey
can help in making land use decisions that will influence
the role of farming in prime land retention.
Soil erosion is the major soil problem of cropland and
pastureland in the San Juan Area. Where the slope is
more than 5 percent, erosion is a hazard. Aceitunas, Al-
mirante, Rio Arriba, and Vega Alta soils, for example,
have slopes of 5 to 12 percent.
The loss of the surface layer through erosion is damag-
ing for two reasons. First, productivity is reduced as the
surface layer is lost and part of the subsoil is incor-
Sporated into the plowed layer. Loss of the surface layer is
especially damaging on soils with a clayey subsoil such as
the Lares, Mabi, and Montegrande soils. Erosion also
reduces productivity on soils that tend to be drought
such as the Catano, Durados, Estacion, and Reilly soils.
Second, soil erosion on farmland results in sediment en-
tering streams and lakes. Control of erosion minimizes
the pollution of streams by sediment and improves quali-
Sty of water for human use, for recreation, and for fish
and wildlife.







SOIL SURVEY


The use of logging equipment is restricted at times
because the soils are slippery when wet. Brush removal,
careful hand planting, and fertilizing increase the survival
of seedlings.
This soil is limited for most urban uses because it is
very steep and subject to landslides. If the soil is used for
construction sites, development should be on the contour.
Removal of vegetation should be held to a minimum, and
temporary plant cover established quickly in denuded
areas. Capability subclass VIIs.


Use and management of the soils
The soil survey is a detailed inventory and evaluation
of the most basic resource of the survey area-the soil. It
is useful in adjusting land use, including urbanization, to
the limitations and potentials of natural resources and the
environment. Also, it can help avoid soil-related failures
in uses of the land.
While a soil survey is in progress, soil scientists, con-
servationists, engineers, and others keep extensive notes
about the nature of the soils and about unique aspects of
behavior of the soils. These notes include data on erosion,
drought damage to specific crops, yield estimates, flood-
ing, the functioning of septic tank disposal systems, and
other factors affecting the productivity, potential, and
limitations of the soils under various uses and manage-
ment. In this way, field experience and measured data on
soil properties and performance are used as a basis for
predicting soil behavior.
Information in this section is useful in planning use and
management of soils for crops, pasture, and woodland and
as sites for buildings, highways and other transportation
systems, sanitary facilities, and parks and other recrea-
tion facilities. From the data presented, the potential of
each soil for specified land uses can be determined, soil
limitations to these land uses can be identified, and costly
failures in houses and other structures, caused by un-
favorable soil properties, can be avoided. A site where
soil properties are favorable can be selected, or practices
that will overcome the soil limitations can be planned.
Planners and others using the soil survey can evaluate
the impact of specific land uses on the overall productivi-
ty of the survey area or other broad planning area and on
the environment. Productivity and the environment are
closely related to the nature of the soil. Plans should
maintain or create a land-use pattern in harmony with the
natural soil.
Contractors can find information that is useful in locat-
ing sources of sand and gravel, roadfill, and topsoil. Other
information indicates the presence of bedrock, wetness, or
very firm soil horizons that cause difficulty in excavation.
Health officials, highway officials, engineers, and many
other specialists also can find useful information in this
soil survey. The safe disposal of wastes, for example, is
closely related to properties of the soil. Pavements, side-
walks, campsites, playgrounds, lawns, and trees and
shrubs are influenced by the nature of the soil.


Crops and pasture
The major management concerns in the use of the soils
for crops and pasture are described in this section. In ad-
dition, the crops or pasture plants best suited to the soil,
including some not commonly grown in the survey area,
are discussed; the system of land capability classification
used by the Soil Conservation Service is explained; and
the estimated yields of the main crops and hay and
pasture plants are presented for each soil.
This section provides information about the overall
agricultural potential of the survey area and about the
management practices that are needed. The information is
useful to equipment dealers, land improvement contrac-
tors, fertilizer companies, processing companies, planners,
conservationists, and others. For each kind of soil, infor-
mation about management is presented in the section
"Soil maps for detailed planning." Planners of manage-
ment systems for individual fields or farms should also
consider the detailed information given in the description
of each soil.
More than 300,000 acres in the survey area was used
for crops and pasture in 1967, according to the Conserva-
tion Needs Inventory. Of this total, more than 89,000
acres was in crops and almost 211,000 acres in pasture.
The potential of the soils of the San Juan Area for in-
creased production of food is good. There is considerable
reserve productive capacity that is not being used for
crops or pasture at the present time. This potential
productive capacity could be further increased by extend-
ing the latest crop production technology to all land suita-
ble for cropland in the survey area. This soil survey can
greatly facilitate the application of such technology.
Acreage in crops and pasture has gradually been
decreasing as more land is used for urban development.
This is especially true in the urban fringe areas near the
San Juan metropolitan area. The use of this soil survey
can help in making land use decisions that will influence
the role of farming in prime land retention.
Soil erosion is the major soil problem of cropland and
pastureland in the San Juan Area. Where the slope is
more than 5 percent, erosion is a hazard. Aceitunas, Al-
mirante, Rio Arriba, and Vega Alta soils, for example,
have slopes of 5 to 12 percent.
The loss of the surface layer through erosion is damag-
ing for two reasons. First, productivity is reduced as the
surface layer is lost and part of the subsoil is incor-
Sporated into the plowed layer. Loss of the surface layer is
especially damaging on soils with a clayey subsoil such as
the Lares, Mabi, and Montegrande soils. Erosion also
reduces productivity on soils that tend to be drought
such as the Catano, Durados, Estacion, and Reilly soils.
Second, soil erosion on farmland results in sediment en-
tering streams and lakes. Control of erosion minimizes
the pollution of streams by sediment and improves quali-
Sty of water for human use, for recreation, and for fish
and wildlife.







SAN JUAN AREA, PUERTO RICO


In many sloping fields, preparing a good seedbed and
tilling are difficult on clayey spots, because the original,
friable surface layer has been eroded away. Such spots
are common in moderately eroded areas of Almirante and
Vega Alta soils.
Erosion control practices provide protective surface
cover, reduce runoff, and increase infiltration. A cropping
system that keeps vegetative cover on the soil for ex-
tended periods can hold soil erosion losses to amounts
that will not reduce the productive capacity of the soils.
On livestock farms, which require pasture and cut
grasses, the legume and grass forage crops reduce erosion
on sloping land and also provide nitrogen and improve
tilth.
Contour tillage or terracing is practical on soils that
have long and regular slopes. On soils with short and ir-
regular slopes, cropping systems that provide substantial
vegetative cover are required to control erosion unless
minimum tillage is practiced. Minimizing tillage and leav-
ing crop residue on the surface help to increase infiltra-
tion and reduce the hazards of runoff and erosion. These
practices can be adapted to most soils in the survey area.
No tillage for row crops is effective in reducing erosion
on sloping land and can be adapted to many soils with
loamy surface layers, but is more difficult to practice suc-
cessfully on soils with a clayey surface layer.
Diversions, terraces, and hillside ditches (fig. 12) reduce
the length of slope and reduce runoff and erosion. They
are more practical on deep, well drained soils that have
regular slopes.
Information for the design of erosion control practices
for each kind of soil is contained in the Technical Guide,
available in the local offices of the Soil Conservation Ser-
vice.
Soil drainage is the major management practice in some
soils of the San Juan Area which are used for crops and
pastures. Some soils are naturally so wet that the produc-
tion of crops common to the area is not generally possible.
These are the very poorly drained Hydraquents, Martin
Pena, and Saladar soils.
Unless artificially drained, some poorly drained and
somewhat poorly drained soils are so wet that crops are
damaged during most years when the seasonal water
table is high. In this category are the Bajura, Sabana
Seca, and Vega Baja soils.
Soils such as the Coloso, Mabi, and Montegrande
require less intensive drainage systems for sustained
production.
The design of drainage systems varies with the kind of
soil. A combination of surface and subsurface drainage is
needed for the poorly drained soils for intensive row
cropping. Drains have to be more closely spaced in soils
with slow permeability than in permeable soils. Finding
adequate outlets for drainage systems is difficult in some
areas of the Bajura, Sabana Seca, and Vega Baja soils. In-
formation on drainage design for each kind of soil is con-
tained in the Technical Guide, available in local offices of
the Soil Conservation Service.


Soil fertility is naturally low in most soils of the coastal
plains of the survey area. These soils are very strongly
acid and leached. Unless limed and fertilized, Aceitunas,
Almirante, Bayamon, Lares, Torres, and Vega Alta soils
have low to moderate productivity. The soils on the flood
plains, such as the Toa, Bajura, and Coloso, range from
neutral to slightly acid and are naturally higher in plant
nutrients.
Some soils of the uplands such as Aibonito, Consumo,
Daguey, Humatas, Limones, and Los Guineos are steep
and very strongly acid, and the fertility is naturally low.
They require applications of lime and fertilizer.
Others, such as Juncos, Morado, and Mucara soils, are
slightly acid and are naturally higher in plant nutrients.
On all soils, additions of lime and fertilizer should be
based on the results of soil tests, on the need of the crop,
and on the expected level of yields.
Soil tilth is an important factor in the germination of
seeds and in the infiltration of water into the soil. Soils
with good tilth are granular and porous.
Many of the soils of the survey area have moderate
amounts of organic matter in the surface layer. Generally
the structure is moderate granular, and physical condition
is good. However, if the erosion is moderate or severe,
the subsoil, which is clayey, is exposed. The subsoil
reduces infiltration and increases runoff. Regular addi-
tions of crop residue, manure, and other organic material
can help to improve soil structure and reduce erosion.
Crops suited to the soils and climate of the San Juan
Area and grown commercially are plantains, bananas,
taniers, yams, sweet potatoes, tobacco, and fruit orchards.
There is high potential for the production of sugarcane
in the San Juan Area.
Special crops, such as tomatoes, green peppers,
cabbage, oranges, grapefruits, limes, chironjas and West
Indian cherries, have high potential in the area. There is
also a high potential for ornamental plants and shrubs in
the uplands and in the coastal plains of the area.
The best adapted species for pasture are stargrass and
pangolagrass and, to some extent, guineagrass.
Commercial plantings of rice are feasible in the
somewhat poorly drained and poorly drained soils of the
flood plains such as the Coloso and Bajura soils.
Coffee, both sun and shade varieties, does very well in
the cooler uplands of the San Juan Area.
Latest information and suggestions for growing these
crops can be obtained from the local offices of the Soil
Conservation Service.

Yields per acre
The average yields per acre that can be expected of the
principal crops under a high level of management are
shown in table 5. In any given year, yields may be higher
or lower than those indicated in the table because of
variations in rainfall and other climatic factors. Absence
of an estimated yield indicates that the crop is not suited
to or not commonly grown on the soil or that a given crop
is not commonly irrigated.







SOIL SURVEY


The estimated yields were based mainly on the ex-
perience and records of farmers, conservationists, and ex-
tension agents. Results of field trials and demonstrations
and available yield data from nearby areas were also con-
sidered.
The yields were estimated assuming that the latest soil
and crop management practices were used. Hay and
pasture yields were estimated for the most productive
varieties of grasses and legumes suited to the climate and
the soil. A few farmers may be obtaining average yields
higher than those shown in table 5.
The management needed to achieve the indicated yields
of the various crops depends on the kind of soil and the
crop. Such management provides drainage, erosion con-
trol, and protection from flooding; the proper planting
and seeding rates; suitable high-yielding crop varieties;
appropriate tillage practices, including time of tillage and
seedbed preparation and tilling when soil moisture is
favorable; control of weeds, plant diseases, and harmful
insects; favorable soil reaction and optimum levels of
nitrogen, phosphorus, potassium, and trace elements for
each crop; effective use of crop residue, barnyard manure,
and green-manure crops; harvesting crops with the smal-
lest possible loss; and timeliness of all fieldwork.
The estimated yields reflect the productive capacity of
the soils for each of the principal crops. Yields are likely
to increase as new production technology is developed.
The productivity of a given soil compared with that of
other soils, however, is not likely to change.
Crops other than those shown in table 5 are grown in
the survey area, but estimated yields are not included
because the acreage of these crops is small. The local of-
fices of the Soil Conservation Service and the Coopera-
tive Extension Service can provide information about the
management concerns and productivity of the soils for
these crops.

Capability classes and subclasses
Capability classes and subclasses show, in a general
way, the suitability of soils for most kinds of field crops.
The soils are classed according to their limitations when
they are used for field crops, the risk of damage when
they are used, and the way they respond to treatment.
The grouping does not take into account major and
generally expensive landforming that would change slope,'
depth, or other characteristics of the soils; does not take
into consideration possible but unlikely major reclamation
projects; and does not apply to rice, cranberries, horticul-
tural crops, or other crops that require special manage-
ment. Capability classification is not a substitute for in-
terpretations designed to show suitability and limitations
of groups of soils for rangeland, for forest trees, or for
engineering purposes.
In the capability system, all kinds of soil are grouped at
three levels: capability class, subclass, and unit. These
levels are defined in the following paragraphs. A survey
area may not have soils of all classes.


Capability classes, the broadest groups, are designated
by Roman numerals I through VIII. The numerals in-
dicate progressively greater limitations and narrower cho-
ices for practical use. The classes are defined as follows:
Class I soils have few limitations that restrict their use.
Class II soils have moderate limitations that reduce the
choice of plants or that require moderate conservation
practices.
Class III soils have severe limitations that reduce the
choice of plants, or that require special conservation prac-
tices, or both.
Class IV soils have very severe limitations that reduce
the choice of plants, or that require very careful manage-
ment, or both.
Class V soils are not likely to erode but have other
limitations, impractical to remove, that limit their use.
Class VI soils have severe limitations that make them
generally unsuitable for cultivation.
Class VII soils have very severe limitations that make
them unsuitable for cultivation.
Class VIII soils and landforms have limitations that
nearly preclude their use for commercial crop production.
Capability subclasses are soil groups within one class;
they are designated by adding a small letter, e, w, s, or c,
to the class numeral, for example, IIe. The letter e shows
that the main limitation is risk of erosion unless close-
growing plant cover is maintained; w shows that water in
or on the soil interferes with plant growth or cultivation
(in some soils the wetness can be partly corrected by ar-
tificial drainage); s shows that the soil is limited mainly
because it is shallow, drought, or stony; and c, used in
only some parts of the United States, shows that the
chief limitation is climate that is too cold or too dry.
In class I there are no subclasses because the soils of
this class have few limitations. Class V contains only the
subclasses indicated by w, s, or c because the soils in class
V are subject to little or no erosion, though they have
other limitations that restrict their use to pasture, range-
land, woodland, wildlife habitat, or recreation.
The acreage of soils in each capability class and sub-
class is indicated in table 6. All soils in the survey area
except those named at a level higher than the series are
included. Some of the soils that are well suited to crops
and pasture may be in low-intensity use, for example,
soils in capability classes I and II. Data in this table can
be used to determine the farming potential of such soils.

Woodland

When Puerto Rico was colonized in the early 1500's, the
island was completely covered by forests, but land clear-
ing for farms was soon begun. By 1880 most of the
forests had been cut. Some areas were unsuitable for per-
manent cultivation and were abandoned when their fer-
tility was lost. Later, some of these areas were again
cleared, cultivated, and abandoned. Land thus abandoned
generally was taken over by inferior volunteer trees.







SOIL SURVEY


The estimated yields were based mainly on the ex-
perience and records of farmers, conservationists, and ex-
tension agents. Results of field trials and demonstrations
and available yield data from nearby areas were also con-
sidered.
The yields were estimated assuming that the latest soil
and crop management practices were used. Hay and
pasture yields were estimated for the most productive
varieties of grasses and legumes suited to the climate and
the soil. A few farmers may be obtaining average yields
higher than those shown in table 5.
The management needed to achieve the indicated yields
of the various crops depends on the kind of soil and the
crop. Such management provides drainage, erosion con-
trol, and protection from flooding; the proper planting
and seeding rates; suitable high-yielding crop varieties;
appropriate tillage practices, including time of tillage and
seedbed preparation and tilling when soil moisture is
favorable; control of weeds, plant diseases, and harmful
insects; favorable soil reaction and optimum levels of
nitrogen, phosphorus, potassium, and trace elements for
each crop; effective use of crop residue, barnyard manure,
and green-manure crops; harvesting crops with the smal-
lest possible loss; and timeliness of all fieldwork.
The estimated yields reflect the productive capacity of
the soils for each of the principal crops. Yields are likely
to increase as new production technology is developed.
The productivity of a given soil compared with that of
other soils, however, is not likely to change.
Crops other than those shown in table 5 are grown in
the survey area, but estimated yields are not included
because the acreage of these crops is small. The local of-
fices of the Soil Conservation Service and the Coopera-
tive Extension Service can provide information about the
management concerns and productivity of the soils for
these crops.

Capability classes and subclasses
Capability classes and subclasses show, in a general
way, the suitability of soils for most kinds of field crops.
The soils are classed according to their limitations when
they are used for field crops, the risk of damage when
they are used, and the way they respond to treatment.
The grouping does not take into account major and
generally expensive landforming that would change slope,'
depth, or other characteristics of the soils; does not take
into consideration possible but unlikely major reclamation
projects; and does not apply to rice, cranberries, horticul-
tural crops, or other crops that require special manage-
ment. Capability classification is not a substitute for in-
terpretations designed to show suitability and limitations
of groups of soils for rangeland, for forest trees, or for
engineering purposes.
In the capability system, all kinds of soil are grouped at
three levels: capability class, subclass, and unit. These
levels are defined in the following paragraphs. A survey
area may not have soils of all classes.


Capability classes, the broadest groups, are designated
by Roman numerals I through VIII. The numerals in-
dicate progressively greater limitations and narrower cho-
ices for practical use. The classes are defined as follows:
Class I soils have few limitations that restrict their use.
Class II soils have moderate limitations that reduce the
choice of plants or that require moderate conservation
practices.
Class III soils have severe limitations that reduce the
choice of plants, or that require special conservation prac-
tices, or both.
Class IV soils have very severe limitations that reduce
the choice of plants, or that require very careful manage-
ment, or both.
Class V soils are not likely to erode but have other
limitations, impractical to remove, that limit their use.
Class VI soils have severe limitations that make them
generally unsuitable for cultivation.
Class VII soils have very severe limitations that make
them unsuitable for cultivation.
Class VIII soils and landforms have limitations that
nearly preclude their use for commercial crop production.
Capability subclasses are soil groups within one class;
they are designated by adding a small letter, e, w, s, or c,
to the class numeral, for example, IIe. The letter e shows
that the main limitation is risk of erosion unless close-
growing plant cover is maintained; w shows that water in
or on the soil interferes with plant growth or cultivation
(in some soils the wetness can be partly corrected by ar-
tificial drainage); s shows that the soil is limited mainly
because it is shallow, drought, or stony; and c, used in
only some parts of the United States, shows that the
chief limitation is climate that is too cold or too dry.
In class I there are no subclasses because the soils of
this class have few limitations. Class V contains only the
subclasses indicated by w, s, or c because the soils in class
V are subject to little or no erosion, though they have
other limitations that restrict their use to pasture, range-
land, woodland, wildlife habitat, or recreation.
The acreage of soils in each capability class and sub-
class is indicated in table 6. All soils in the survey area
except those named at a level higher than the series are
included. Some of the soils that are well suited to crops
and pasture may be in low-intensity use, for example,
soils in capability classes I and II. Data in this table can
be used to determine the farming potential of such soils.

Woodland

When Puerto Rico was colonized in the early 1500's, the
island was completely covered by forests, but land clear-
ing for farms was soon begun. By 1880 most of the
forests had been cut. Some areas were unsuitable for per-
manent cultivation and were abandoned when their fer-
tility was lost. Later, some of these areas were again
cleared, cultivated, and abandoned. Land thus abandoned
generally was taken over by inferior volunteer trees.







SAN JUAN AREA, PUERTO RICO


According to the 1967 Conservation Needs Inventory,
there was a total of 72,239 acres of woodland: 11,637 acres
of commercial forests and 60,602 of noncommercial
forests. The total forested acreage is about 16 percent of
the San Juan Area.
Forest is an excellent use of the soils of the San Juan
Area for the protection of soil and water resources.
Forest cover can minimize floods, reduce the amount of
soil material lost as sediment in rivers, and hold runoff
into periods of dry weather. Some natural noncommercial
forests should be converted to commercial. Others should
be protected and left in their natural state. Trees should
be planted in some nonforested areas.
Species having the best potential for the San Juan area
are Honduras pine, Honduras mahogany, kadam, teak, and
eucalyptus.

Woodland management and productivity
Table 7 contains information useful to woodland owners
or forest managers planning use of soils for wood crops.
Mapping unit symbols for soils suitable for wood crops
are listed, and the ordination (woodland suitability) sym-
bol for each soil is given. All soils bearing the same or-
dination symbol require the same general kinds of
woodland management and have about the same potential
productivity.
The first part of the ordination symbol, a number, in-
dicates the potential productivity of the soils for impor-
tant trees. The number 1 indicates very high productivity;
2, high; 3, moderately high; 4, moderate; and 5, low. The
second part of the symbol, a letter, indicates the major
kind of soil limitation. The letter x indicates stoniness or
rockiness; w, excessive water in or on the soil; t, toxic
substances in the soil; d, restricted root depth; c, clay in
the upper part of the soil; s, sandy texture; f, high con-
tent of coarse fragments in the soil profile; and r, steep
slopes. The letter o indicates insignificant limitations or
restrictions. If a soil has more than one limitation, priori-
ty in placing the soil into a limitation class is in the fol-
lowing order: x, w, t, d, c, s, f, and r.
In table 7 the soils are also rated for a number of fac-
tors to be considered in management. Slight, moderate,
and severe are used to indicate the degree of major soil
limitations.
Ratings of the erosion hazard indicate the risk of loss
of soil in well managed woodland. The risk is slight if the
expected soil loss is small, moderate if some measures are
needed to control erosion during logging and road con-
struction, and severe if intensive management or special
equipment and methods are needed to prevent excessive
loss of soil.
Ratings of equipment limitation reflect the charac-
teristics and conditions of the soil that restrict use of the
equipment generally needed in woodland management or
harvesting. A rating of slight indicates that use of equip-
ment is not limited to a particular kind of equipment or
time of year; moderate indicates a short seasonal limita-


tion or a need for some modification in management or
equipment; severe indicates a seasonal limitation, a need
for special equipment or management, or a hazard in the
use of equipment.
Seedling mortality ratings indicate the degree that the
soil affects expected mortality of planted tree seedlings.
Plant competition is not considered in the ratings.
Seedlings from good planting stock that are properly
planted during a period of sufficient rainfall are rated. A
rating of slight indicates that the expected mortality of
the planted seedlings is less than 25 percent; moderate, 25
to 50 percent; and severe, more than 50 percent.
The potential productivity of merchantable or impor-
tant trees on a soil is expressed as the average yearly
growth in board feet per acre. The trees listed are not na-
tive, but appear to be those best suited to the soil. The
figures for average yearly growth are estimates. Impor-
tant trees are those that woodland managers generally
favor in intermediate or improvement cuttings. They are
selected on the basis of growth rate, quality, value, and
marketability.
Trees to plant are those that are suitable for commer-
cial wood production and that are suited to the soils.

Engineering

This section provides information about the use of soils
for building sites, sanitary facilities, construction material,
and water management. Among those who can benefit
from this information are engineers, landowners, commu-
nity planners, town and city managers, land developers,
builders, contractors, and farmers and ranchers.
The ratings in the engineering tables are based on test
data and estimated data in the "Soil properties" section.
The ratings were determined jointly by soil scientists and
engineers of the Soil Conservation Service using known
relationships between the soil properties and the behavior
of soils in various engineering uses.
Among the soil properties and site conditions identified
by a soil survey and used in determining the ratings in
this section were grain-size distribution, liquid limit,
plasticity index, soil reaction, depth to bedrock, hardness
of bedrock that is within 5 or 6 feet of the surface, soil
wetness, depth to a seasonal high water table, slope,
likelihood of flooding, natural soil structure or aggrega-
tion, in-place soil density, and geologic origin of the soil
material. Where pertinent, data about kinds of clay
minerals, mineralogy of the sand and silt fractions, and
the kind of absorbed cations were also considered.
On the basis of information assembled about soil pro-
perties, ranges of values can be estimated for erodibility,
permeability, corrosivity, shrink-swell potential, available
water capacity, shear strength, compressibility, slope sta-
bility, and other factors of expected soil behavior in en-
gineering uses. As appropriate, these values can be ap-
plied to each major horizon of each soil or to the entire
profile.







SAN JUAN AREA, PUERTO RICO


According to the 1967 Conservation Needs Inventory,
there was a total of 72,239 acres of woodland: 11,637 acres
of commercial forests and 60,602 of noncommercial
forests. The total forested acreage is about 16 percent of
the San Juan Area.
Forest is an excellent use of the soils of the San Juan
Area for the protection of soil and water resources.
Forest cover can minimize floods, reduce the amount of
soil material lost as sediment in rivers, and hold runoff
into periods of dry weather. Some natural noncommercial
forests should be converted to commercial. Others should
be protected and left in their natural state. Trees should
be planted in some nonforested areas.
Species having the best potential for the San Juan area
are Honduras pine, Honduras mahogany, kadam, teak, and
eucalyptus.

Woodland management and productivity
Table 7 contains information useful to woodland owners
or forest managers planning use of soils for wood crops.
Mapping unit symbols for soils suitable for wood crops
are listed, and the ordination (woodland suitability) sym-
bol for each soil is given. All soils bearing the same or-
dination symbol require the same general kinds of
woodland management and have about the same potential
productivity.
The first part of the ordination symbol, a number, in-
dicates the potential productivity of the soils for impor-
tant trees. The number 1 indicates very high productivity;
2, high; 3, moderately high; 4, moderate; and 5, low. The
second part of the symbol, a letter, indicates the major
kind of soil limitation. The letter x indicates stoniness or
rockiness; w, excessive water in or on the soil; t, toxic
substances in the soil; d, restricted root depth; c, clay in
the upper part of the soil; s, sandy texture; f, high con-
tent of coarse fragments in the soil profile; and r, steep
slopes. The letter o indicates insignificant limitations or
restrictions. If a soil has more than one limitation, priori-
ty in placing the soil into a limitation class is in the fol-
lowing order: x, w, t, d, c, s, f, and r.
In table 7 the soils are also rated for a number of fac-
tors to be considered in management. Slight, moderate,
and severe are used to indicate the degree of major soil
limitations.
Ratings of the erosion hazard indicate the risk of loss
of soil in well managed woodland. The risk is slight if the
expected soil loss is small, moderate if some measures are
needed to control erosion during logging and road con-
struction, and severe if intensive management or special
equipment and methods are needed to prevent excessive
loss of soil.
Ratings of equipment limitation reflect the charac-
teristics and conditions of the soil that restrict use of the
equipment generally needed in woodland management or
harvesting. A rating of slight indicates that use of equip-
ment is not limited to a particular kind of equipment or
time of year; moderate indicates a short seasonal limita-


tion or a need for some modification in management or
equipment; severe indicates a seasonal limitation, a need
for special equipment or management, or a hazard in the
use of equipment.
Seedling mortality ratings indicate the degree that the
soil affects expected mortality of planted tree seedlings.
Plant competition is not considered in the ratings.
Seedlings from good planting stock that are properly
planted during a period of sufficient rainfall are rated. A
rating of slight indicates that the expected mortality of
the planted seedlings is less than 25 percent; moderate, 25
to 50 percent; and severe, more than 50 percent.
The potential productivity of merchantable or impor-
tant trees on a soil is expressed as the average yearly
growth in board feet per acre. The trees listed are not na-
tive, but appear to be those best suited to the soil. The
figures for average yearly growth are estimates. Impor-
tant trees are those that woodland managers generally
favor in intermediate or improvement cuttings. They are
selected on the basis of growth rate, quality, value, and
marketability.
Trees to plant are those that are suitable for commer-
cial wood production and that are suited to the soils.

Engineering

This section provides information about the use of soils
for building sites, sanitary facilities, construction material,
and water management. Among those who can benefit
from this information are engineers, landowners, commu-
nity planners, town and city managers, land developers,
builders, contractors, and farmers and ranchers.
The ratings in the engineering tables are based on test
data and estimated data in the "Soil properties" section.
The ratings were determined jointly by soil scientists and
engineers of the Soil Conservation Service using known
relationships between the soil properties and the behavior
of soils in various engineering uses.
Among the soil properties and site conditions identified
by a soil survey and used in determining the ratings in
this section were grain-size distribution, liquid limit,
plasticity index, soil reaction, depth to bedrock, hardness
of bedrock that is within 5 or 6 feet of the surface, soil
wetness, depth to a seasonal high water table, slope,
likelihood of flooding, natural soil structure or aggrega-
tion, in-place soil density, and geologic origin of the soil
material. Where pertinent, data about kinds of clay
minerals, mineralogy of the sand and silt fractions, and
the kind of absorbed cations were also considered.
On the basis of information assembled about soil pro-
perties, ranges of values can be estimated for erodibility,
permeability, corrosivity, shrink-swell potential, available
water capacity, shear strength, compressibility, slope sta-
bility, and other factors of expected soil behavior in en-
gineering uses. As appropriate, these values can be ap-
plied to each major horizon of each soil or to the entire
profile.







SOIL SURVEY


These factors of soil behavior affect construction and
maintenance of roads, airport runways, pipelines, founda-
tions for small buildings, ponds and small dams, irrigation
projects, drainage systems, sewage and refuse disposal
systems, and other engineering works. The ranges of
values can be used to (1) select potential residential, com-
mercial, industrial, and recreational uses; (2) make
preliminary estimates pertinent to construction in a par-
ticular area; (3) evaluate alternative routes for roads,
streets, highways, pipelines, and underground cables; (4)
evaluate alternative sites for location of sanitary landfills,
onsite sewage disposal systems, and other waste disposal
facilities; (5) plan detailed onsite investigations of soils
and geology; (6) find sources of gravel, sand, clay, and
topsoil; (7) plan farm drainage systems, irrigation
systems, ponds, terraces, and other structures for soil and
water conservation; (8) relate performance of structures
already built to the properties of the kinds of soil on
which they are built so that performance of similar struc-
tures on the same or a similar soil in other locations can
be predicted; and (9) predict the trafficability of soils for
cross-country movement of vehicles and construction
equipment.
Data presented in this section are useful for land-use
planning and for choosing alternative practices or
general designs that will overcome unfavorable soil pro-
perties and minimize soil-related failures. Limitations to
the use of these data, however, should be well understood.
First, the data are generally not presented for soil
material below a depth of 5 or 6 feet. Also, because of the
scale of the detailed map in this soil survey, small areas
of soils that differ from the dominant soil may be in-
cluded in mapping. Thus, these data do not eliminate the
need for onsite investigations, testing, and analysis by
personnel having expertise in the specific use contem-
plated.
The information is presented mainly in tables. Table 8
shows, for each kind of soil, the degree and kind of limita-
tions for building site development; table 9, for sanitary
facilities; and table 11, for water management. Table 10
shows the suitability of each kind of soil as a source of
construction materials.
The information in the tables, along with the soil map,
the soil descriptions, and other data provided in this sur-
vey, can be used to make additional interpretations and to
construct interpretive maps for specific uses of land.
Some of the terms used in this soil survey have a spe-
cial meaning in soil science. Many of these terms are
defined in the Glossary.

Building site development
The degree and kind of soil limitations that affect shal-
low excavations, dwellings with and without basements,
small commercial buildings, and local roads and streets
are indicated in table 8. A slight limitation indicates that
soil properties generally are favorable for the specified
use; any limitation is minor and easily overcome. A


moderate limitation indicates that soil properties and site
features are unfavorable for the specified use, but the
limitations can be overcome or minimized by special
planning and design. A severe limitation indicates that one
or more soil properties or site features are so unfavorable
or difficult to overcome that a major increase in construc-
tion effort, special design, or intensive maintenance is
required. For some soils rated severe, such costly mea-
sures may not be feasible.
Shallow excavations are made for pipelines, sewerlines,
communications and power transmission lines, basements,
and open ditches. Such digging or trenching is influenced
by soil wetness caused by a seasonal high water table; the
texture and consistence of soils; the tendency of soils to
cave in or slough; and the presence of very firm, dense
soil layers, bedrock, or large stones. In addition, excava-
tions are affected by slope of the soil and the probability
of flooding. Ratings do not apply to soil horizons below a
depth of 6 feet unless otherwise noted.
In the soil series descriptions, the consistence of each
soil horizon is given, and the presence of very firm or ex-
tremely firm horizons, usually difficult to excavate, is in-
dicated.
Dwellings without basements and small commercial
buildings referred to in table 8 are built on undisturbed
soil and have foundation loads of a dwelling no more than
three stories high. Separate ratings are made for small
commercial buildings without basements and for
dwellings without basements. For such structures, soils
should be sufficiently stable that cracking or subsidence
of the structure from settling or shear failure of the foun-
dation does not occur. These ratings were determined
from estimates of the shear strength, compressibility, and
shrink-swell potential of the soil. Soil texture, plasticity
and in-place density, potential frost action, soil wetness,
and depth to a seasonal high water table were also con-
sidered. Soil wetness and depth to a seasonal high water
table indicate potential difficulty in providing adequate
drainage for basements, lawns, and gardens. Depth to
bedrock, slope, and large stones in or on the soil are also
important considerations in the choice of sites for these
structures and were considered in determining the
ratings. Susceptibility to flooding is a serious hazard.
Local roads and streets referred to in table 8 have an
all-weather surface that can carry light to medium traffic
all year. They consist of a subgrade of the underlying soil
material; a base of gravel, crushed rock fragments, or soil
material stabilized with lime or cement; and a flexible or
rigid surface, commonly asphalt or concrete. The roads
are graded with soil material at hand, and most cuts and
fills are less than 6 feet deep.
The load supporting capacity and the stability of the
soil as well as the quantity and workability of fill material
available are important in design and construction of
roads and streets. The classifications of the soil and the
soil texture, density, shrink-swell potential, and potential
frost action are indicators of the traffic supporting capaci-
ty used in making the ratings. Soil wetness, flooding,







SAN JUAN AREA, PUERTO RICO


slope, depth to hard rock or very compact layers, and con-
tent of large stones affect stability and ease of excava-
tion.

Sanitary facilities
Favorable soil properties and site features are needed
for proper functioning of septic tank absorption fields,
sewage lagoons, and sanitary landfills. The nature of the
soil is important in selecting sites for these facilities and
in identifying limiting soil properties and site features to
be considered in design and installation. Also, those soil
properties that affect ease of excavation or installation of
these facilities will be of interest to contractors and local
officials. Table 9 shows the degree and kind of limitations
of each soil for such uses and for use of the. soil as daily
cover for landfills. It is important to observe local or-
dinances and regulations.
If the degree of soil limitation is expressed as slight,
soils are generally favorable for the specified use and
limitations are minor and easily overcome; if moderate,
soil properties or site features are unfavorable for the
specified use, but limitations can be overcome by special
planning and design; and if severe, soil properties or site
features are so unfavorable or difficult to overcome that
major soil reclamation, special designs, or intensive main-
tenance is required. Soil suitability is rated by the terms
good, fair, or poor, which, respectively, mean about the
same as the terms slight, moderate, and severe.
Septic tank absorption fields are subsurface systems of
tile or perforated pipe that distribute effluent from a sep-
tic tank into the natural soil. Only the soil horizons
between depths of 18 and 72 inches are evaluated for this
use. The soil properties and site features considered are
those that affect the absorption of the effluent and those
that affect the construction of the system.
Properties and features that affect absorption of the
effluent are permeability, depth to seasonal high water
table, depth to bedrock, and susceptibility to flooding.
Stones, boulders, and shallowness to bedrock interfere
with installation. Excessive slope can cause lateral
seepage and surfacing of the effluent. Also, soil erosion
and soil slippage are hazards if absorption fields are in-
stalled on sloping soils.
In some soils, loose sand and gravel or fractured
bedrock is less than 4 feet below the tile lines. In these
soils the absorption field does not adequately filter the ef-
fluent, and ground water in the area may be con-
taminated.
On many of the soils that have moderate or severe
limitations for use as septic tank absorption fields, a
system to lower the seasonal water table can be installed
or the size of the absorption field can be increased so that
performance is satisfactory.
Sewage lagoons are shallow ponds constructed to hold
sewage while aerobic bacteria decompose the solid and
liquid wastes. Lagoons have a nearly level floor and cut
slopes or embankments of compacted soil material. Aero-


bic lagoons generally are designed to hold sewage within
a depth of 2 to 5 feet. Nearly impervious soil material for
the lagoon floor and sides is required to minimize seepage
and contamination of ground water. Soils that are very
high in content of organic matter and those that have
cobbles, stones, or boulders are not suitable. Unless the
soil has very slow permeability, contamination of ground
water is a hazard where the seasonal high water table is
above the level of the lagoon floor. In soils where the
water table is seasonally high, seepage of ground water
into the lagoon can seriously reduce the lagoon's capacity
for liquid waste. Slope, depth to bedrock, and susceptibili-
ty to flooding also affect the suitability of sites for
sewage lagoons or the cost of construction. Shear
strength and permeability of compacted soil material af-
fect the performance of embankments.
Sanitary landfill is a method of disposing of solid
waste by placing refuse in successive layers either in ex-
cavated trenches or on the surface of the soil. The waste
is spread, compacted, and covered daily with a thin layer
of soil material. Landfill areas are subject to heavy
vehicular traffic. Risk of polluting ground water and traf-
ficability affect the suitability of a soil for this use. The
best soils have a loamy or silty texture, have moderate to
slow permeability, are deep to a seasonal water table, and
are not subject to flooding. Clayey soils are likely to be
sticky and difficult to spread. Sandy or gravelly soils
generally have rapid permeability, which might allow nox-
ious liquids to contaminate ground water. Soil wetness
can be a limitation, because operating heavy equipment
on a wet soil is difficult. Seepage into the refuse increases
the risk of pollution of ground water.
Ease of excavation affects the suitability of a soil for
the trench type of landfill. A suitable soil is deep to
bedrock and free of large stones and boulders. If the
seasonal water table is high, water will seep into
trenches.
Unless otherwise stated, the limitations in table 9 apply
only to the soil material within a depth of about 6 feet. If
the trench is deeper, a limitation of slight or moderate
may not be valid. Site investigation is needed before a
site is selected.
Daily cover for landfill should be soil that is easy to
excavate and spread over the compacted fill in wet and
dry periods. Soils that are loamy or silty and free of
stones or boulders are better than other soils. Clayey
soils may be sticky and difficult to spread; sandy soils
may be subject to soil blowing.
The soils selected for final cover of landfills should be
suitable for growing plants. Of all the horizons, the A
horizon in most soils has the best workability, more or-
ganic matter, and the best potential for growing plants.
Thus, for either the area- or trench-type landfill, stockpil-
ing material from the A horizon for use as the surface
layer of the final cover is desirable.
Where it is necessary to bring in soil material for daily
or final cover, thickness of suitable soil material available
and depth to a seasonal high water table in soils sur-







SOIL SURVEY


rounding the sites should be evaluated. Other factors to
be evaluated are those that affect reclamation of the bor-
row areas. These factors include slope, erodibility, and
potential for plant growth.

Construction materials
The suitability of each soil as a source of roadfill, sand,
gravel, and topsoil is indicated in table 10 by ratings of
good, fair, or poor. The texture, thickness, and organic-
matter content of each soil horizon are important factors
in rating soils for use as construction materials. Each soil
is evaluated to the depth observed, generally about 6 feet.
Roadfill is soil material used in embankments for
roads. Soils are evaluated as a source of roadfill for low
embankments, which generally are less than 6 feet high
and less exacting in design than high embankments. The
ratings reflect the ease of excavating and working the
material and the expected performance of the material
where it has been compacted and adequately drained. The
performance of soil after it is stabilized with lime or ce-
ment is not considered in the ratings, but information
about some of the soil properties that influence such per-
formance is given in the descriptions of the soil series.
The ratings apply to the soil material between the A
horizon and a depth of 5 to 6 feet. It is assumed that soil
horizons will be mixed during excavation and spreading.
Many soils have horizons of contrasting suitability within
their profile. The estimated engineering properties in
table 13 provide specific information about the nature of
each horizon. This information can help determine the
suitability of each horizon for roadfill.
Soils rated good are coarse grained. They have low
shrink-swell potential, low potential frost action, and few
cobbles and stones. They are at least moderately well
drained and have slopes of 15 percent or less. Soils rated
fair have a plasticity index of less than 15 and have other
limiting features, such as moderate shrink-swell potential,
moderately steep slopes, wetness, or many stones. If the
thickness of suitable material is less than 3 feet, the en-
tire soil is rated poor.
Sand and gravel are used in great quantities in many
kinds of construction. The ratings in table 10 provide
guidance as to where to look for probable sources and are
based on the probability that soils in a given area contain
sizable quantities of sand or gravel. A soil rated good or
fair has a layer of suitable material at least 3 feet thick,
the top of which is within a depth of 6 feet. Coarse frag-
ments of soft bedrock material, such as shale and silt-
stone, are not considered to be sand and gravel. Fine-
grained soils are not suitable sources of sand and gravel.
The ratings do not take into account depth to the water
table or other factors that affect excavation of the
material. Descriptions of grain size, kinds of minerals,
reaction, and stratification are given in the soil series
descriptions and in table 13.
Topsoil is used in areas where vegetation is to be
established and maintained. Suitability is affected mainly


by the ease of working and spreading the soil material in
preparing a seedbed and by the ability of the soil material
to support plantlife. Also considered is the damage that
can result at the area from which the topsoil is taken.
The ease of excavation is influenced by the thickness of
suitable material, wetness, slope, and amount of stones.
The ability of the soil to support plantlife is determined
by texture, structure, and the amount of soluble salts or
toxic substances. Organic matter in the Al or Ap horizon
greatly increases the absorption and retention of moisture
and nutrients. Therefore, the soil material from these
horizons should be carefully preserved for later use.
Soils rated good have at least 16 inches of friable loamy
material at their surface. They are free of stones and cob-
bles, are low in content of gravel, and have gentle slopes.
They are low in soluble salts that can limit or prevent
plant growth. They are naturally fertile or respond well
to fertilizer. They are not so wet that excavation is dif-
ficult during most of the year.
Soils rated fair are loose sandy soils or firm loamy or
clayey soils in which the suitable material is only 8 to 16
inches thick or soils that have appreciable amounts of
gravel, stones, or soluble salt.
Soils rated poor are very sandy soils and very firm
clayey soils; soils with suitable layers less than 8 inches
thick; soils having large amounts of gravel, stones, or
soluble salt; steep soils; and poorly drained soils.
Although a rating of good is not based entirely on high
content of organic matter, a surface horizon is generally
preferred for topsoil because of its organic-matter con-
tent. This horizon is designated as Al or Ap in the soil se-
ries descriptions. The absorption and retention of
moisture and nutrients for plant growth are greatly in-
creased by organic matter.

Water management
Many soil properties and site features that affect water
management practices have been identified in this soil
survey. In table 11 soil and site features that affect use
are indicated for each kind of soil. This information is sig-
nificant in planning, installing, and maintaining water con-
trol structures.
Pond reservoir areas hold water behind a dam or em-
bankment. Soils best suited to this use have a low
seepage potential, which is determined by permeability
and the depth to fractured or permeable bedrock or other
permeable material.
Embankments, dikes, and levees require soil material
that is resistant to seepage, erosion, and piping and has
favorable stability, shrink-swell potential, shear strength,
and compaction characteristics. Large stones and organic
matter in a soil downgrade the suitability of a soil for use
in embankments, dikes, and levees.
Drainage of soil is affected by such soil properties as
permeability; texture; depth to bedrock, hardpan, or other
layers that affect the rate of water movement; depth to
the water table; slope; stability of ditchbanks; suscepti-







SOIL SURVEY


rounding the sites should be evaluated. Other factors to
be evaluated are those that affect reclamation of the bor-
row areas. These factors include slope, erodibility, and
potential for plant growth.

Construction materials
The suitability of each soil as a source of roadfill, sand,
gravel, and topsoil is indicated in table 10 by ratings of
good, fair, or poor. The texture, thickness, and organic-
matter content of each soil horizon are important factors
in rating soils for use as construction materials. Each soil
is evaluated to the depth observed, generally about 6 feet.
Roadfill is soil material used in embankments for
roads. Soils are evaluated as a source of roadfill for low
embankments, which generally are less than 6 feet high
and less exacting in design than high embankments. The
ratings reflect the ease of excavating and working the
material and the expected performance of the material
where it has been compacted and adequately drained. The
performance of soil after it is stabilized with lime or ce-
ment is not considered in the ratings, but information
about some of the soil properties that influence such per-
formance is given in the descriptions of the soil series.
The ratings apply to the soil material between the A
horizon and a depth of 5 to 6 feet. It is assumed that soil
horizons will be mixed during excavation and spreading.
Many soils have horizons of contrasting suitability within
their profile. The estimated engineering properties in
table 13 provide specific information about the nature of
each horizon. This information can help determine the
suitability of each horizon for roadfill.
Soils rated good are coarse grained. They have low
shrink-swell potential, low potential frost action, and few
cobbles and stones. They are at least moderately well
drained and have slopes of 15 percent or less. Soils rated
fair have a plasticity index of less than 15 and have other
limiting features, such as moderate shrink-swell potential,
moderately steep slopes, wetness, or many stones. If the
thickness of suitable material is less than 3 feet, the en-
tire soil is rated poor.
Sand and gravel are used in great quantities in many
kinds of construction. The ratings in table 10 provide
guidance as to where to look for probable sources and are
based on the probability that soils in a given area contain
sizable quantities of sand or gravel. A soil rated good or
fair has a layer of suitable material at least 3 feet thick,
the top of which is within a depth of 6 feet. Coarse frag-
ments of soft bedrock material, such as shale and silt-
stone, are not considered to be sand and gravel. Fine-
grained soils are not suitable sources of sand and gravel.
The ratings do not take into account depth to the water
table or other factors that affect excavation of the
material. Descriptions of grain size, kinds of minerals,
reaction, and stratification are given in the soil series
descriptions and in table 13.
Topsoil is used in areas where vegetation is to be
established and maintained. Suitability is affected mainly


by the ease of working and spreading the soil material in
preparing a seedbed and by the ability of the soil material
to support plantlife. Also considered is the damage that
can result at the area from which the topsoil is taken.
The ease of excavation is influenced by the thickness of
suitable material, wetness, slope, and amount of stones.
The ability of the soil to support plantlife is determined
by texture, structure, and the amount of soluble salts or
toxic substances. Organic matter in the Al or Ap horizon
greatly increases the absorption and retention of moisture
and nutrients. Therefore, the soil material from these
horizons should be carefully preserved for later use.
Soils rated good have at least 16 inches of friable loamy
material at their surface. They are free of stones and cob-
bles, are low in content of gravel, and have gentle slopes.
They are low in soluble salts that can limit or prevent
plant growth. They are naturally fertile or respond well
to fertilizer. They are not so wet that excavation is dif-
ficult during most of the year.
Soils rated fair are loose sandy soils or firm loamy or
clayey soils in which the suitable material is only 8 to 16
inches thick or soils that have appreciable amounts of
gravel, stones, or soluble salt.
Soils rated poor are very sandy soils and very firm
clayey soils; soils with suitable layers less than 8 inches
thick; soils having large amounts of gravel, stones, or
soluble salt; steep soils; and poorly drained soils.
Although a rating of good is not based entirely on high
content of organic matter, a surface horizon is generally
preferred for topsoil because of its organic-matter con-
tent. This horizon is designated as Al or Ap in the soil se-
ries descriptions. The absorption and retention of
moisture and nutrients for plant growth are greatly in-
creased by organic matter.

Water management
Many soil properties and site features that affect water
management practices have been identified in this soil
survey. In table 11 soil and site features that affect use
are indicated for each kind of soil. This information is sig-
nificant in planning, installing, and maintaining water con-
trol structures.
Pond reservoir areas hold water behind a dam or em-
bankment. Soils best suited to this use have a low
seepage potential, which is determined by permeability
and the depth to fractured or permeable bedrock or other
permeable material.
Embankments, dikes, and levees require soil material
that is resistant to seepage, erosion, and piping and has
favorable stability, shrink-swell potential, shear strength,
and compaction characteristics. Large stones and organic
matter in a soil downgrade the suitability of a soil for use
in embankments, dikes, and levees.
Drainage of soil is affected by such soil properties as
permeability; texture; depth to bedrock, hardpan, or other
layers that affect the rate of water movement; depth to
the water table; slope; stability of ditchbanks; suscepti-







SAN JUAN AREA, PUERTO RICO


ability to flooding; salinity and alkalinity; and availability
of outlets for drainage.
Terraces and diversions are embankments or a com-
bination of channels and ridges constructed across a slope
to intercept runoff. They allow water to soak into the soil
or flow slowly to an outlet. Features that affect suitabili-
ty of a soil for terraces are uniformity and steepness of
slope; depth to bedrock, hardpan, or other unfavorable
material; large stones; permeability; ease of establishing
vegetation; and resistance to water erosion, soil blowing,
soil slipping, and piping.
Grassed waterways are constructed to channel runoff to
outlets at a nonerosive velocity. Features that affect the
use of soils for waterways are slope, permeability, erodi-
bility, wetness, and suitability for permanent vegetation.

Recreation
The soils of the survey area are rated in table 12 ac-
cording to limitations that affect their suitability for
recreation uses. The ratings are based on such restrictive
soil features as flooding, wetness, slope, and texture of
the surface layer. Not considered in these ratings, but im-
portant in evaluating a site, are location and accessibility
of the area, size and shape of the area and its scenic
quality, the ability of the soil to support vegetation, ac-
cess to water, potential water impoundment sites availa-
ble, and either access to public sewerlines or capacity of
the soil to absorb septic tank effluent. Soils subject to
flooding are limited, in varying degree, for recreation use
by the duration and intensity of flooding and the season
when flooding occurs. Onsite assessment of height, dura-
tion, intensity, and frequency of flooding is essential in
planning recreation facilities.
The degree of the limitation of the soils is expressed as
slight, moderate, or severe. Slight means that the soil pro-
perties are generally favorable and that the limitations
are minor and easily overcome. Moderate means that the
limitations can be overcome or alleviated by planning,
design, or special maintenance. Severe means that soil
properties are unfavorable and that limitations can be off-
set only by costly soil reclamation, special design, inten-
sive maintenance, limited use, or by a combination of
these measures.
The information in table 12 can be supplemented by in-
formation in other parts of this survey. Especially helpful
are interpretations for septic tank absorption fields, given
in table 9, and interpretations for dwellings without base-
ments and for local roads and streets, given in table 8.
Camp areas require such site preparation as shaping
and leveling for tent and parking areas, stabilizing roads
and intensively used areas, and installing sanitary facili-
ties and utility lines. Camp areas are subject to heavy
foot traffic and some vehicular traffic. The best soils for
this use have mild slopes and are not wet or subject to
flooding during the period of use. The surface has few or
no stones or boulders, absorbs rainfall readily but remains
firm, and is not dusty when dry. Strong slopes and stones


or boulders can greatly increase the cost of constructing
camping sites.
Picnic areas are subject to heavy foot traffic. Most
vehicular traffic is confined to access roads and parking
areas. The best soils for use as picnic areas are firm when
wet, are not dusty when dry, are not subject to flooding
during the period of use, and do not have slopes or stones
or boulders that will increase the cost of shaping sites or
of building access roads and parking areas.
Playgrounds require soils that can withstand intensive
foot traffic. The best soils are almost level and are not
wet or subject to flooding during the season of use. The
surface is free of stones or boulders, is firm after rains,
and is not dusty when dry. If shaping is required to ob-
tain a uniform grade, the depth of the soil over bedrock
or hardpan should be enough to allow necessary grading.
Paths and trails for walking, horseback riding,
bicycling, and other uses should require little or no
cutting and filling. The best soils for this use are those
that are not wet, are firm after rains, are not dusty when
dry, and are not subject to flooding more than once dur-
ing the annual period of use. They should have moderate
slopes and have few or no stones or boulders on the sur-
face.


Soil properties

Extensive data about soil properties are summarized on
the following pages. The two main sources of these data
are the many thousands of soil borings made during the
course of the survey and the laboratory analyses of
selected soil samples from typical profiles.
In making soil borings during field mapping, soil
scientists can identify several important soil properties.
They note the seasonal soil moisture condition or the
presence of free water and its depth. For each horizon in
the profile, they note the thickness and color of the soil
material; the texture, or amount of clay, silt, sand, and
gravel or other coarse fragments; the structure, or the
natural pattern of cracks and pores in the undisturbed
soil; and the consistence of the soil material in place
under the existing soil moisture conditions. They record
the depth of plant roots, determine the pH or reaction of
the soil, and identify any free carbonates.
Samples of soil material are analyzed in the laboratory
to verify the field estimates of soil properties and to
determine all major properties of key soils, especially pro-
perties that cannot be estimated accurately by field ob-
servation. Laboratory analyses are not conducted for all
soil series in the survey area, but laboratory data for
many soil series not tested are available from nearby sur-
vey areas.
The available field and laboratory data are summarized
in tables. The tables give the estimated range of en-
gineering properties, the engineering classifications, and
the physical and chemical properties of each major
horizon of each soil in the survey area. They also present
data about pertinent soil and water features.







SAN JUAN AREA, PUERTO RICO


ability to flooding; salinity and alkalinity; and availability
of outlets for drainage.
Terraces and diversions are embankments or a com-
bination of channels and ridges constructed across a slope
to intercept runoff. They allow water to soak into the soil
or flow slowly to an outlet. Features that affect suitabili-
ty of a soil for terraces are uniformity and steepness of
slope; depth to bedrock, hardpan, or other unfavorable
material; large stones; permeability; ease of establishing
vegetation; and resistance to water erosion, soil blowing,
soil slipping, and piping.
Grassed waterways are constructed to channel runoff to
outlets at a nonerosive velocity. Features that affect the
use of soils for waterways are slope, permeability, erodi-
bility, wetness, and suitability for permanent vegetation.

Recreation
The soils of the survey area are rated in table 12 ac-
cording to limitations that affect their suitability for
recreation uses. The ratings are based on such restrictive
soil features as flooding, wetness, slope, and texture of
the surface layer. Not considered in these ratings, but im-
portant in evaluating a site, are location and accessibility
of the area, size and shape of the area and its scenic
quality, the ability of the soil to support vegetation, ac-
cess to water, potential water impoundment sites availa-
ble, and either access to public sewerlines or capacity of
the soil to absorb septic tank effluent. Soils subject to
flooding are limited, in varying degree, for recreation use
by the duration and intensity of flooding and the season
when flooding occurs. Onsite assessment of height, dura-
tion, intensity, and frequency of flooding is essential in
planning recreation facilities.
The degree of the limitation of the soils is expressed as
slight, moderate, or severe. Slight means that the soil pro-
perties are generally favorable and that the limitations
are minor and easily overcome. Moderate means that the
limitations can be overcome or alleviated by planning,
design, or special maintenance. Severe means that soil
properties are unfavorable and that limitations can be off-
set only by costly soil reclamation, special design, inten-
sive maintenance, limited use, or by a combination of
these measures.
The information in table 12 can be supplemented by in-
formation in other parts of this survey. Especially helpful
are interpretations for septic tank absorption fields, given
in table 9, and interpretations for dwellings without base-
ments and for local roads and streets, given in table 8.
Camp areas require such site preparation as shaping
and leveling for tent and parking areas, stabilizing roads
and intensively used areas, and installing sanitary facili-
ties and utility lines. Camp areas are subject to heavy
foot traffic and some vehicular traffic. The best soils for
this use have mild slopes and are not wet or subject to
flooding during the period of use. The surface has few or
no stones or boulders, absorbs rainfall readily but remains
firm, and is not dusty when dry. Strong slopes and stones


or boulders can greatly increase the cost of constructing
camping sites.
Picnic areas are subject to heavy foot traffic. Most
vehicular traffic is confined to access roads and parking
areas. The best soils for use as picnic areas are firm when
wet, are not dusty when dry, are not subject to flooding
during the period of use, and do not have slopes or stones
or boulders that will increase the cost of shaping sites or
of building access roads and parking areas.
Playgrounds require soils that can withstand intensive
foot traffic. The best soils are almost level and are not
wet or subject to flooding during the season of use. The
surface is free of stones or boulders, is firm after rains,
and is not dusty when dry. If shaping is required to ob-
tain a uniform grade, the depth of the soil over bedrock
or hardpan should be enough to allow necessary grading.
Paths and trails for walking, horseback riding,
bicycling, and other uses should require little or no
cutting and filling. The best soils for this use are those
that are not wet, are firm after rains, are not dusty when
dry, and are not subject to flooding more than once dur-
ing the annual period of use. They should have moderate
slopes and have few or no stones or boulders on the sur-
face.


Soil properties

Extensive data about soil properties are summarized on
the following pages. The two main sources of these data
are the many thousands of soil borings made during the
course of the survey and the laboratory analyses of
selected soil samples from typical profiles.
In making soil borings during field mapping, soil
scientists can identify several important soil properties.
They note the seasonal soil moisture condition or the
presence of free water and its depth. For each horizon in
the profile, they note the thickness and color of the soil
material; the texture, or amount of clay, silt, sand, and
gravel or other coarse fragments; the structure, or the
natural pattern of cracks and pores in the undisturbed
soil; and the consistence of the soil material in place
under the existing soil moisture conditions. They record
the depth of plant roots, determine the pH or reaction of
the soil, and identify any free carbonates.
Samples of soil material are analyzed in the laboratory
to verify the field estimates of soil properties and to
determine all major properties of key soils, especially pro-
perties that cannot be estimated accurately by field ob-
servation. Laboratory analyses are not conducted for all
soil series in the survey area, but laboratory data for
many soil series not tested are available from nearby sur-
vey areas.
The available field and laboratory data are summarized
in tables. The tables give the estimated range of en-
gineering properties, the engineering classifications, and
the physical and chemical properties of each major
horizon of each soil in the survey area. They also present
data about pertinent soil and water features.







SOIL SURVEY


Engineering properties

Table 13 gives estimates of engineering properties and
classifications for the major horizons of each soil in the
survey area.
Most soils have, within the upper 5 or 6 feet, horizons
of contrasting properties. Table 13 gives information for
each of these contrasting horizons in a typical profile.
Depth to the upper and lower boundaries of each horizon
is indicated. More information about the range in depth
and about other properties in each horizon is given for
each soil series in the section "Soil series and morpholo-
gy."
Texture is described in table 13 in the standard terms
used by the U.S. Department of Agriculture. These terms
are defined according to percentages of sand, silt, and
clay in soil material that is less than 2 millimeters in
diameter. "Loam," for example, is soil material that is 7 to
27 percent clay, 28 to 50 percent silt, and less than 52 per-
cent sand. If a soil contains gravel or other particles
coarser than sand, an appropriate modifier is added, for
example, "gravelly loam." Other texture terms are
defined in the Glossary.
The two systems commonly used in classifying soils for
engineering use are the Unified Soil Classification System
(Unified) (2) and the system adopted by the American
Association of State Highway and Transportation Offi-
cials (AASHTO) (1).
The Unified system classifies soils according to proper-
ties that affect their use as construction material. Soils
are classified according to grain-size distribution of the
fraction less than 3 inches in diameter, plasticity index,
liquid limit, and organic-matter content. Soils are grouped
into 15 classes-eight classes of coarse-grained soils,
identified as GW, GP, GM, GC, SW, SP, SM, and SC; six
classes of fine-grained soils, identified as ML, CL, OL,
MH, CH, and OH; and one class of highly organic soils,
identified as Pt. Soils on the borderline between two
classes have a dual classification symbol, for example, CL-
ML.
The AASHTO system classifies soils according to those
properties that affect their use in highway construction
and maintenance. In this system a mineral soil is clas-
sified in one of seven basic groups ranging from A-1
through A-7 on the basis of grain-size distribution, liquid
limit, and plasticity index. Soils in group A-1 are coarse
grained and low in content of fines. At the other extreme,
in group A-7, are fine-grained soils. Highly organic soils
are classified in group A-8 on the basis of visual inspec-
tion.
When laboratory data are available, the A-i, A-2, and
A-7 groups are further classified as follows: A-i-a, A-l-b,
A-2-4, A-2-5, A-2-6, A-2-7, A-7-5, and A-7-6. As an addi-
tional refinement, the desirability of soils as subgrade
material can be indicated by a group index number. These
numbers range from 0 for the best subgrade material to
20 or higher for the poorest. The estimated classification,
without group index numbers, is given in table 13. Also in


table 13 the percentage, by weight, of rock fragments
more than 3 inches in diameter is estimated for each
major horizon. These estimates are determined mainly by
observing volume percentage in the field and then con-
verting that, by formula, to weight percentage.
Percentage of the soil material less than 3 inches in
diameter that passes each of four sieves (U.S. standard)
is estimated for each major horizon. The estimates are
based on tests of soils that were sampled in the survey
area and in nearby areas and on field estimates from
many borings made during the survey.
Liquid limit and plasticity index indicate the effect of
water on the strength and consistence of soil. These in-
dexes are used in both the Unified and AASHTO soil
classification systems. They are also used as indicators in
making general predictions of soil behavior. Range in
liquid limit and plasticity index are estimated on the basis
of test data from the survey area or from nearby areas
and on observations of the many soil borings made during
the survey.
The estimates are rounded to the nearest 5 percent.
Thus, if the ranges of gradation and Atterburg limits ex-
tend a marginal amount across classification boundaries (1
or 2 percent), the classification in the marginal zone is
omitted.

Physical and chemical properties
Table 14 shows estimated values for several soil charac-
teristics and features that affect behavior of soils in en-
gineering uses. These estimates are given for each major
horizon, at the depths indicated, in the typical pedon of
each soil. The estimates are based on field observations
and on test data for these and similar soils.
Permeability is estimated on the basis of known rela-
tionships among the soil characteristics observed in the
field-particularly soil structure, porosity, and gradation
or texture-that influence the downward movement of
water in the soil. The estimates are for vertical water
movement when the soil is saturated. Not considered in
the estimates is lateral seepage or such transient soil fea-
tures as plowpans and surface crusts. Permeability of the
soil is an important factor to be considered in planning
and designing drainage systems, in evaluating the poten-
tial of soils for septic tank systems and other waste
disposal systems, and in many other aspects of land use
and management.
Available water capacity is rated on the basis of soil
characteristics that influence the ability of the soil to hold
water and make it available to plants. Important charac-
teristics are content of organic matter, soil texture, and
soil structure. Shallow-rooted plants are not likely to use
the available water from the deeper soil horizons. Availa-
ble water capacity is an important factor in the choice of
plants or crops to be grown and in the design of irrigation
systems.
Soil reaction is expressed as a range in pH values. The
range in pH of each major horizon is based on many field







SOIL SURVEY


Engineering properties

Table 13 gives estimates of engineering properties and
classifications for the major horizons of each soil in the
survey area.
Most soils have, within the upper 5 or 6 feet, horizons
of contrasting properties. Table 13 gives information for
each of these contrasting horizons in a typical profile.
Depth to the upper and lower boundaries of each horizon
is indicated. More information about the range in depth
and about other properties in each horizon is given for
each soil series in the section "Soil series and morpholo-
gy."
Texture is described in table 13 in the standard terms
used by the U.S. Department of Agriculture. These terms
are defined according to percentages of sand, silt, and
clay in soil material that is less than 2 millimeters in
diameter. "Loam," for example, is soil material that is 7 to
27 percent clay, 28 to 50 percent silt, and less than 52 per-
cent sand. If a soil contains gravel or other particles
coarser than sand, an appropriate modifier is added, for
example, "gravelly loam." Other texture terms are
defined in the Glossary.
The two systems commonly used in classifying soils for
engineering use are the Unified Soil Classification System
(Unified) (2) and the system adopted by the American
Association of State Highway and Transportation Offi-
cials (AASHTO) (1).
The Unified system classifies soils according to proper-
ties that affect their use as construction material. Soils
are classified according to grain-size distribution of the
fraction less than 3 inches in diameter, plasticity index,
liquid limit, and organic-matter content. Soils are grouped
into 15 classes-eight classes of coarse-grained soils,
identified as GW, GP, GM, GC, SW, SP, SM, and SC; six
classes of fine-grained soils, identified as ML, CL, OL,
MH, CH, and OH; and one class of highly organic soils,
identified as Pt. Soils on the borderline between two
classes have a dual classification symbol, for example, CL-
ML.
The AASHTO system classifies soils according to those
properties that affect their use in highway construction
and maintenance. In this system a mineral soil is clas-
sified in one of seven basic groups ranging from A-1
through A-7 on the basis of grain-size distribution, liquid
limit, and plasticity index. Soils in group A-1 are coarse
grained and low in content of fines. At the other extreme,
in group A-7, are fine-grained soils. Highly organic soils
are classified in group A-8 on the basis of visual inspec-
tion.
When laboratory data are available, the A-i, A-2, and
A-7 groups are further classified as follows: A-i-a, A-l-b,
A-2-4, A-2-5, A-2-6, A-2-7, A-7-5, and A-7-6. As an addi-
tional refinement, the desirability of soils as subgrade
material can be indicated by a group index number. These
numbers range from 0 for the best subgrade material to
20 or higher for the poorest. The estimated classification,
without group index numbers, is given in table 13. Also in


table 13 the percentage, by weight, of rock fragments
more than 3 inches in diameter is estimated for each
major horizon. These estimates are determined mainly by
observing volume percentage in the field and then con-
verting that, by formula, to weight percentage.
Percentage of the soil material less than 3 inches in
diameter that passes each of four sieves (U.S. standard)
is estimated for each major horizon. The estimates are
based on tests of soils that were sampled in the survey
area and in nearby areas and on field estimates from
many borings made during the survey.
Liquid limit and plasticity index indicate the effect of
water on the strength and consistence of soil. These in-
dexes are used in both the Unified and AASHTO soil
classification systems. They are also used as indicators in
making general predictions of soil behavior. Range in
liquid limit and plasticity index are estimated on the basis
of test data from the survey area or from nearby areas
and on observations of the many soil borings made during
the survey.
The estimates are rounded to the nearest 5 percent.
Thus, if the ranges of gradation and Atterburg limits ex-
tend a marginal amount across classification boundaries (1
or 2 percent), the classification in the marginal zone is
omitted.

Physical and chemical properties
Table 14 shows estimated values for several soil charac-
teristics and features that affect behavior of soils in en-
gineering uses. These estimates are given for each major
horizon, at the depths indicated, in the typical pedon of
each soil. The estimates are based on field observations
and on test data for these and similar soils.
Permeability is estimated on the basis of known rela-
tionships among the soil characteristics observed in the
field-particularly soil structure, porosity, and gradation
or texture-that influence the downward movement of
water in the soil. The estimates are for vertical water
movement when the soil is saturated. Not considered in
the estimates is lateral seepage or such transient soil fea-
tures as plowpans and surface crusts. Permeability of the
soil is an important factor to be considered in planning
and designing drainage systems, in evaluating the poten-
tial of soils for septic tank systems and other waste
disposal systems, and in many other aspects of land use
and management.
Available water capacity is rated on the basis of soil
characteristics that influence the ability of the soil to hold
water and make it available to plants. Important charac-
teristics are content of organic matter, soil texture, and
soil structure. Shallow-rooted plants are not likely to use
the available water from the deeper soil horizons. Availa-
ble water capacity is an important factor in the choice of
plants or crops to be grown and in the design of irrigation
systems.
Soil reaction is expressed as a range in pH values. The
range in pH of each major horizon is based on many field







SAN JUAN AREA, PUERTO RICO


checks. For many soils, the values have been verified by
laboratory analyses. Soil reaction is important in selecting
the crops, ornamental plants, or other plants to be grown;
in evaluating soil amendments for fertility and stabiliza-
tion; and in evaluating the corrosivity of soils.
Shrink-swell potential depends mainly on the amount
and kind of clay in the soil. Laboratory measurements of
the swelling of undisturbed clods were made for many
soils. For others the swelling was estimated on the basis
of the kind and amount of clay in the soil and on mea-
surements of similar soils. The size of the load and the
magnitude of the change in soil moisture content also in-
fluence the swelling of soils. Shrinking and swelling of
some soils can cause damage to building foundations,
basement walls, roads, and other structures unless special
designs are used. A high shrink-swell potential indicates.
that special design and added expense may be required if
the planned use of the soil will not tolerate large volume
changes.
Risk of corrosion pertains to potential soil-induced
chemical action that dissolves or weakens uncoated steel
or concrete. The rate of corrosion of uncoated steel is re-
lated to soil moisture, particle-size distribution, total acidi-
ty, and electrical conductivity of the soil material. The
rate of corrosion of concrete is based mainly on the
sulfate content, texture, and acidity of the soil. Protective
measures for steel or more resistant concrete help to
avoid or minimize damage resulting from the corrosion.
Uncoated steel intersecting soil boundaries or soil
horizons is more susceptible to corrosion than an installa-
tion that is entirely within one kind of soil or within one
soil horizon.
Erosion factors are used to predict the erodibility of a
soil and its tolerance to erosion in relation to specific
kinds of land use and treatment. The soil erodibility fac-
tor (K) is a measure of the susceptibility of the soil to
erosion by water. Soils having the highest K values are
the most erodible. K values range from 0.10 to 0.64. To
estimate annual soil loss per acre, the K value of a soil is
modified by factors representing plant cover, grade and
length of slope, management practices, and climate. The
soil-loss tolerance factor (T) is the maximum rate of soil
erosion, whether from rainfall or soil blowing, that can
occur without reducing crop production or environmental
quality. The rate is expressed in tons of soil loss per acre
per year.

Soil and water features

Table 15 contains information helpful in planning land
uses and engineering projects that are likely to be af-
fected by soil and water features.
Hydrologic soil groups are used to estimate runoff
from precipitation. Soils not protected by vegetation are
placed in one of four groups on the basis of the intake of
water after the soils have been wetted and have received
precipitation from long-duration storms.
The four hydrologic soil groups are:


Group A. Soils having a high infiltration rate (low ru-
noff potential) when thoroughly wet. These consist chiefly
of deep, well drained to excessively drained sands or
gravels. These soils have a high rate of water transmis-
sion.
Group B. Soils having a moderate infiltration rate when
thoroughly wet. These consist chiefly of moderately deep
or deep, moderately well drained or well drained soils
that have moderately fine texture to moderately coarse
texture. These soils have a moderate rate of water trans-
mission.
Group C. Soils having a slow infiltration rate when
thoroughly wet. These consist chiefly of soils that have a
layer that impedes the downward movement of water or
soils that have moderately fine texture or fine texture.
These soils have a slow rate of water transmission.
Group D. Soils having a very slow infiltration rate (high
runoff potential) when thoroughly wet. These consist
chiefly of clay soils that have a high shrink-swell poten-
tial, soils that have a permanent high water table, soils
that have a claypan or clay layer at or near the surface,
and soils that are shallow over nearly impervious materi-
al. These soils have a very slow rate of water transmis-
sion.
Flooding is the temporary covering of soil with water
from overflowing streams, with runoff from adjacent
slopes, and by tides. Water standing for short periods
after rains or after snow melts is not considered flooding,
nor is water in swamps and marshes. Flooding is rated in
general terms that describe the frequency and duration of
flooding and the time of year when flooding is most like-
ly. The ratings are based on evidence in the soil profile of
the effects of flooding, namely thin strata of gravel, sand,
silt, or, in places, clay deposited by floodwater; irregular
decrease in organic-matter content with increasing depth;
and absence of distinctive soil horizons that form in soils
of the area that are not subject to flooding. The ratings
are also based on local information about floodwater
levels in the area and the extent of flooding and on infor-
mation that relates the position of each soil on the land-
scape to historic floods.
The generalized description of flood hazards is of value
in land-use planning and provides a valid basis for land-
use restrictions. The soil data are less specific, however,
than those provided by detailed engineering surveys that
delineate flood-prone areas at specific flood frequency
levels.
High water table is the highest level of a saturated
zone more than 6 inches thick for a continuous period of
more than 2 weeks during most years. The depth to a
seasonal high water table applies to undrained soils. Esti-
mates are based mainly on the relationship between gray-
ish colors or mottles in the soil and the depth to free
water observed in many borings made during the course
of the soil survey. Indicated in table 15 are the depth to
the seasonal high water table; the kind of water table,
that is, perched, artesian, or apparent; and the months of
the year that the water table commonly is high. Only
saturated zones above a depth of 5 or 6 feet are indicated.







SOIL SURVEY


Information about the seasonal high water table helps
in assessing the need for specially designed foundations,
the need for specific kinds of drainage systems, and the
need for footing drains to insure dry basements. Such in-
formation is also needed to decide whether or not con-
struction of basements is feasible and to determine how
septic tank absorption fields and other underground in-
stallations will function. Also, a seasonal high water table
affects ease of excavation.
Depth to bedrock is shown for all soils that are under-
lain by bedrock at a depth of 5 to 6 feet or less. For many
soils, the limited depth to bedrock is a part of the defini-
tion of the soil series. The depths shown are based on
measurements made in many soil borings and on other
observations during the mapping of the soils. The kind of
bedrock and its hardness as related to ease of excavation
is also shown. Rippable bedrock can be excavated with a
single-tooth ripping attachment on a 200-horsepower trac-
tor, but hard bedrock generally requires blasting.
Subsidence is the settlement of organic soils or of soils
containing semifluid layers. Initial subsidence generally
results from drainage. Total subsidence is initial sub-
sidence plus the slow sinking that occurs over a period of
several years as a result of the oxidation or compression
of organic material.


Classification of soils

This section describes the soil series of the survey area,
defines the current system of classifying soils, and classi-
fies the soils of the area according to that system.

Soil series and morphology

In this section, each soil series recognized in the survey
area is described in detail. The descriptions are arranged
in alphabetic order by series name.
Characteristics of the soil and the material in which it
formed are discussed for each series. The soil is then
compared to similar soils and to nearby soils of other se-
ries. Then a pedon, a small three-dimensional area of soil
that is typical of the soil series in the survey area, is
described. The detailed descriptions of each soil horizon
follow standards in the Soil Survey Manual (3). Unless
otherwise noted, colors described are for moist soil.
Following the pedon description is the range of impor-
tant characteristics of the soil series in this survey area.
Phases, or mapping units, of each soil series are described
in the section "Soil maps for detailed planning."

Aceitunas series
The Aceitunas series consists of clayey, oxidic,
isohyperthermic Typic Palehumults. These soils are deep,
well drained, and have a B2 horizon of yellowish red clay.
They formed in fine textured sediments washed from
limestone. The Aceitunas soils are on alluvial fans and in
valleys. Slopes range from 2 to 12 percent, but are domi-


nantly 5 to 12 percent. The mean annual precipitation is
66 inches, and the mean annual temperature is 77 degrees
F.
The Aceitunas soils are associated with the Via, Rio
Arriba, and Mabi soils, but the clayey subsoil is not so ex-
pansive as that of those soils.
Typical pedon of Aceitunas clay, 5 to 12 percent slopes,
0.8 kilometer south of intersection of Highway 250 and
Highway 1, then 25 feet west in a pangolagrass field.
Ap-0 to 8 inches, dark brown (7.5YR 4/4) clay; weak fine subangular
blocky structure; friable, slightly sticky, slightly plastic; many fine
roots; few fine dark concretions; few fine pores; few krotovinas;
very strongly acid; clear smooth boundary.
B21t-8 to 15 inches, yellowish red (5YR 4/6) clay; moderate fine suban-
gular blocky structure; firm, slightly sticky, slightly plastic; many
fine roots; common dead dark roots; few krotovinas; few fine pores;
very strongly acid; gradual smooth boundary.
B22t-15 to 30 inches, yellowish red (5YR 4/8) clay; moderate medium
subangular blocky structure; firm, slightly sticky, slightly plastic;
common dead roots; common patchy clay films; few pores; few fine
roots; few fine weathered rock fragments; very strongly acid;
gradual smooth boundary.
B23t-30 to 43 inches, yellowish red (5YR 4/8) clay; weak fine subangu-
lar blocky structure; friable, slightly sticky, slightly plastic; few
dead roots; few pores; few weathered rock fragments; few patchy
clay films on ped surfaces; very strongly acid; gradual smooth boun-
dary.
B24t-43 to 60 inches, yellowish red (5YR 4/8) clay; weak fine subangu-
lar blocky structure; friable, slightly sticky, slightly plastic; common
fine dark stains; patchy clay films, very strongly acid.
The solum is more than 60 inches thick. Reaction throughout is
strongly acid to very strongly acid.
The A horizon has hue of 7.5YR or 5YR, value of 3 or 4, and chroma
of 3 or 4.
The B2t horizon has hue of 5YR and 2.5YR, value of 4 to 6, and
chroma of 6 to 8. It has weak to moderate fine and medium subangular
blocky structure.

Aibonito series
The Aibonito series consists of clayey, oxidic,
isohyperthermic Orthoxic Tropohumults. These soils are
deep, well drained, and have a B2 horizon of strong
brown clay. They formed in residuum of volcanic rocks.
The Aibonito soils are on side slopes and ridgetops of vol-
canic uplands. Slopes range from 12 to 40 percent, but are
dominantly 20 to 40 percent. The mean annual precipita-
tion is 90 inches, and the mean annual temperature is 75
degrees F.
The Aibonito soils are associated with the Catalina,
Comerio, and Mucara soils. They have a thinner solum
than the Catalina and Comerio soils and a thicker solum
than the Mucara soils.
Typical pedon of Aibonito clay, 20 to 40 percent slopes,
5 feet east from kilometer 6.2 of Highway 162, Aibonito,
P.R.
Ap-0 to 7 inches, dark grayish brown (10YR 4/2) clay; moderate fine
subangular blocky structure; very hard, friable, slightly sticky,
plastic; many fine roots; very strongly acid; abrupt irregular boun-
dary.
B1-7 to 11 inches, strong brown (7.5YR 5/6) clay; common fine distinct
yellowish red (5YR 4/6) mottles in ped interiors and brown (10YR
4/3) coatings on ped surfaces; extremely firm, sticky, plastic; few







SOIL SURVEY


Information about the seasonal high water table helps
in assessing the need for specially designed foundations,
the need for specific kinds of drainage systems, and the
need for footing drains to insure dry basements. Such in-
formation is also needed to decide whether or not con-
struction of basements is feasible and to determine how
septic tank absorption fields and other underground in-
stallations will function. Also, a seasonal high water table
affects ease of excavation.
Depth to bedrock is shown for all soils that are under-
lain by bedrock at a depth of 5 to 6 feet or less. For many
soils, the limited depth to bedrock is a part of the defini-
tion of the soil series. The depths shown are based on
measurements made in many soil borings and on other
observations during the mapping of the soils. The kind of
bedrock and its hardness as related to ease of excavation
is also shown. Rippable bedrock can be excavated with a
single-tooth ripping attachment on a 200-horsepower trac-
tor, but hard bedrock generally requires blasting.
Subsidence is the settlement of organic soils or of soils
containing semifluid layers. Initial subsidence generally
results from drainage. Total subsidence is initial sub-
sidence plus the slow sinking that occurs over a period of
several years as a result of the oxidation or compression
of organic material.


Classification of soils

This section describes the soil series of the survey area,
defines the current system of classifying soils, and classi-
fies the soils of the area according to that system.

Soil series and morphology

In this section, each soil series recognized in the survey
area is described in detail. The descriptions are arranged
in alphabetic order by series name.
Characteristics of the soil and the material in which it
formed are discussed for each series. The soil is then
compared to similar soils and to nearby soils of other se-
ries. Then a pedon, a small three-dimensional area of soil
that is typical of the soil series in the survey area, is
described. The detailed descriptions of each soil horizon
follow standards in the Soil Survey Manual (3). Unless
otherwise noted, colors described are for moist soil.
Following the pedon description is the range of impor-
tant characteristics of the soil series in this survey area.
Phases, or mapping units, of each soil series are described
in the section "Soil maps for detailed planning."

Aceitunas series
The Aceitunas series consists of clayey, oxidic,
isohyperthermic Typic Palehumults. These soils are deep,
well drained, and have a B2 horizon of yellowish red clay.
They formed in fine textured sediments washed from
limestone. The Aceitunas soils are on alluvial fans and in
valleys. Slopes range from 2 to 12 percent, but are domi-


nantly 5 to 12 percent. The mean annual precipitation is
66 inches, and the mean annual temperature is 77 degrees
F.
The Aceitunas soils are associated with the Via, Rio
Arriba, and Mabi soils, but the clayey subsoil is not so ex-
pansive as that of those soils.
Typical pedon of Aceitunas clay, 5 to 12 percent slopes,
0.8 kilometer south of intersection of Highway 250 and
Highway 1, then 25 feet west in a pangolagrass field.
Ap-0 to 8 inches, dark brown (7.5YR 4/4) clay; weak fine subangular
blocky structure; friable, slightly sticky, slightly plastic; many fine
roots; few fine dark concretions; few fine pores; few krotovinas;
very strongly acid; clear smooth boundary.
B21t-8 to 15 inches, yellowish red (5YR 4/6) clay; moderate fine suban-
gular blocky structure; firm, slightly sticky, slightly plastic; many
fine roots; common dead dark roots; few krotovinas; few fine pores;
very strongly acid; gradual smooth boundary.
B22t-15 to 30 inches, yellowish red (5YR 4/8) clay; moderate medium
subangular blocky structure; firm, slightly sticky, slightly plastic;
common dead roots; common patchy clay films; few pores; few fine
roots; few fine weathered rock fragments; very strongly acid;
gradual smooth boundary.
B23t-30 to 43 inches, yellowish red (5YR 4/8) clay; weak fine subangu-
lar blocky structure; friable, slightly sticky, slightly plastic; few
dead roots; few pores; few weathered rock fragments; few patchy
clay films on ped surfaces; very strongly acid; gradual smooth boun-
dary.
B24t-43 to 60 inches, yellowish red (5YR 4/8) clay; weak fine subangu-
lar blocky structure; friable, slightly sticky, slightly plastic; common
fine dark stains; patchy clay films, very strongly acid.
The solum is more than 60 inches thick. Reaction throughout is
strongly acid to very strongly acid.
The A horizon has hue of 7.5YR or 5YR, value of 3 or 4, and chroma
of 3 or 4.
The B2t horizon has hue of 5YR and 2.5YR, value of 4 to 6, and
chroma of 6 to 8. It has weak to moderate fine and medium subangular
blocky structure.

Aibonito series
The Aibonito series consists of clayey, oxidic,
isohyperthermic Orthoxic Tropohumults. These soils are
deep, well drained, and have a B2 horizon of strong
brown clay. They formed in residuum of volcanic rocks.
The Aibonito soils are on side slopes and ridgetops of vol-
canic uplands. Slopes range from 12 to 40 percent, but are
dominantly 20 to 40 percent. The mean annual precipita-
tion is 90 inches, and the mean annual temperature is 75
degrees F.
The Aibonito soils are associated with the Catalina,
Comerio, and Mucara soils. They have a thinner solum
than the Catalina and Comerio soils and a thicker solum
than the Mucara soils.
Typical pedon of Aibonito clay, 20 to 40 percent slopes,
5 feet east from kilometer 6.2 of Highway 162, Aibonito,
P.R.
Ap-0 to 7 inches, dark grayish brown (10YR 4/2) clay; moderate fine
subangular blocky structure; very hard, friable, slightly sticky,
plastic; many fine roots; very strongly acid; abrupt irregular boun-
dary.
B1-7 to 11 inches, strong brown (7.5YR 5/6) clay; common fine distinct
yellowish red (5YR 4/6) mottles in ped interiors and brown (10YR
4/3) coatings on ped surfaces; extremely firm, sticky, plastic; few







SOIL SURVEY


Information about the seasonal high water table helps
in assessing the need for specially designed foundations,
the need for specific kinds of drainage systems, and the
need for footing drains to insure dry basements. Such in-
formation is also needed to decide whether or not con-
struction of basements is feasible and to determine how
septic tank absorption fields and other underground in-
stallations will function. Also, a seasonal high water table
affects ease of excavation.
Depth to bedrock is shown for all soils that are under-
lain by bedrock at a depth of 5 to 6 feet or less. For many
soils, the limited depth to bedrock is a part of the defini-
tion of the soil series. The depths shown are based on
measurements made in many soil borings and on other
observations during the mapping of the soils. The kind of
bedrock and its hardness as related to ease of excavation
is also shown. Rippable bedrock can be excavated with a
single-tooth ripping attachment on a 200-horsepower trac-
tor, but hard bedrock generally requires blasting.
Subsidence is the settlement of organic soils or of soils
containing semifluid layers. Initial subsidence generally
results from drainage. Total subsidence is initial sub-
sidence plus the slow sinking that occurs over a period of
several years as a result of the oxidation or compression
of organic material.


Classification of soils

This section describes the soil series of the survey area,
defines the current system of classifying soils, and classi-
fies the soils of the area according to that system.

Soil series and morphology

In this section, each soil series recognized in the survey
area is described in detail. The descriptions are arranged
in alphabetic order by series name.
Characteristics of the soil and the material in which it
formed are discussed for each series. The soil is then
compared to similar soils and to nearby soils of other se-
ries. Then a pedon, a small three-dimensional area of soil
that is typical of the soil series in the survey area, is
described. The detailed descriptions of each soil horizon
follow standards in the Soil Survey Manual (3). Unless
otherwise noted, colors described are for moist soil.
Following the pedon description is the range of impor-
tant characteristics of the soil series in this survey area.
Phases, or mapping units, of each soil series are described
in the section "Soil maps for detailed planning."

Aceitunas series
The Aceitunas series consists of clayey, oxidic,
isohyperthermic Typic Palehumults. These soils are deep,
well drained, and have a B2 horizon of yellowish red clay.
They formed in fine textured sediments washed from
limestone. The Aceitunas soils are on alluvial fans and in
valleys. Slopes range from 2 to 12 percent, but are domi-


nantly 5 to 12 percent. The mean annual precipitation is
66 inches, and the mean annual temperature is 77 degrees
F.
The Aceitunas soils are associated with the Via, Rio
Arriba, and Mabi soils, but the clayey subsoil is not so ex-
pansive as that of those soils.
Typical pedon of Aceitunas clay, 5 to 12 percent slopes,
0.8 kilometer south of intersection of Highway 250 and
Highway 1, then 25 feet west in a pangolagrass field.
Ap-0 to 8 inches, dark brown (7.5YR 4/4) clay; weak fine subangular
blocky structure; friable, slightly sticky, slightly plastic; many fine
roots; few fine dark concretions; few fine pores; few krotovinas;
very strongly acid; clear smooth boundary.
B21t-8 to 15 inches, yellowish red (5YR 4/6) clay; moderate fine suban-
gular blocky structure; firm, slightly sticky, slightly plastic; many
fine roots; common dead dark roots; few krotovinas; few fine pores;
very strongly acid; gradual smooth boundary.
B22t-15 to 30 inches, yellowish red (5YR 4/8) clay; moderate medium
subangular blocky structure; firm, slightly sticky, slightly plastic;
common dead roots; common patchy clay films; few pores; few fine
roots; few fine weathered rock fragments; very strongly acid;
gradual smooth boundary.
B23t-30 to 43 inches, yellowish red (5YR 4/8) clay; weak fine subangu-
lar blocky structure; friable, slightly sticky, slightly plastic; few
dead roots; few pores; few weathered rock fragments; few patchy
clay films on ped surfaces; very strongly acid; gradual smooth boun-
dary.
B24t-43 to 60 inches, yellowish red (5YR 4/8) clay; weak fine subangu-
lar blocky structure; friable, slightly sticky, slightly plastic; common
fine dark stains; patchy clay films, very strongly acid.
The solum is more than 60 inches thick. Reaction throughout is
strongly acid to very strongly acid.
The A horizon has hue of 7.5YR or 5YR, value of 3 or 4, and chroma
of 3 or 4.
The B2t horizon has hue of 5YR and 2.5YR, value of 4 to 6, and
chroma of 6 to 8. It has weak to moderate fine and medium subangular
blocky structure.

Aibonito series
The Aibonito series consists of clayey, oxidic,
isohyperthermic Orthoxic Tropohumults. These soils are
deep, well drained, and have a B2 horizon of strong
brown clay. They formed in residuum of volcanic rocks.
The Aibonito soils are on side slopes and ridgetops of vol-
canic uplands. Slopes range from 12 to 40 percent, but are
dominantly 20 to 40 percent. The mean annual precipita-
tion is 90 inches, and the mean annual temperature is 75
degrees F.
The Aibonito soils are associated with the Catalina,
Comerio, and Mucara soils. They have a thinner solum
than the Catalina and Comerio soils and a thicker solum
than the Mucara soils.
Typical pedon of Aibonito clay, 20 to 40 percent slopes,
5 feet east from kilometer 6.2 of Highway 162, Aibonito,
P.R.
Ap-0 to 7 inches, dark grayish brown (10YR 4/2) clay; moderate fine
subangular blocky structure; very hard, friable, slightly sticky,
plastic; many fine roots; very strongly acid; abrupt irregular boun-
dary.
B1-7 to 11 inches, strong brown (7.5YR 5/6) clay; common fine distinct
yellowish red (5YR 4/6) mottles in ped interiors and brown (10YR
4/3) coatings on ped surfaces; extremely firm, sticky, plastic; few







SOIL SURVEY


Information about the seasonal high water table helps
in assessing the need for specially designed foundations,
the need for specific kinds of drainage systems, and the
need for footing drains to insure dry basements. Such in-
formation is also needed to decide whether or not con-
struction of basements is feasible and to determine how
septic tank absorption fields and other underground in-
stallations will function. Also, a seasonal high water table
affects ease of excavation.
Depth to bedrock is shown for all soils that are under-
lain by bedrock at a depth of 5 to 6 feet or less. For many
soils, the limited depth to bedrock is a part of the defini-
tion of the soil series. The depths shown are based on
measurements made in many soil borings and on other
observations during the mapping of the soils. The kind of
bedrock and its hardness as related to ease of excavation
is also shown. Rippable bedrock can be excavated with a
single-tooth ripping attachment on a 200-horsepower trac-
tor, but hard bedrock generally requires blasting.
Subsidence is the settlement of organic soils or of soils
containing semifluid layers. Initial subsidence generally
results from drainage. Total subsidence is initial sub-
sidence plus the slow sinking that occurs over a period of
several years as a result of the oxidation or compression
of organic material.


Classification of soils

This section describes the soil series of the survey area,
defines the current system of classifying soils, and classi-
fies the soils of the area according to that system.

Soil series and morphology

In this section, each soil series recognized in the survey
area is described in detail. The descriptions are arranged
in alphabetic order by series name.
Characteristics of the soil and the material in which it
formed are discussed for each series. The soil is then
compared to similar soils and to nearby soils of other se-
ries. Then a pedon, a small three-dimensional area of soil
that is typical of the soil series in the survey area, is
described. The detailed descriptions of each soil horizon
follow standards in the Soil Survey Manual (3). Unless
otherwise noted, colors described are for moist soil.
Following the pedon description is the range of impor-
tant characteristics of the soil series in this survey area.
Phases, or mapping units, of each soil series are described
in the section "Soil maps for detailed planning."

Aceitunas series
The Aceitunas series consists of clayey, oxidic,
isohyperthermic Typic Palehumults. These soils are deep,
well drained, and have a B2 horizon of yellowish red clay.
They formed in fine textured sediments washed from
limestone. The Aceitunas soils are on alluvial fans and in
valleys. Slopes range from 2 to 12 percent, but are domi-


nantly 5 to 12 percent. The mean annual precipitation is
66 inches, and the mean annual temperature is 77 degrees
F.
The Aceitunas soils are associated with the Via, Rio
Arriba, and Mabi soils, but the clayey subsoil is not so ex-
pansive as that of those soils.
Typical pedon of Aceitunas clay, 5 to 12 percent slopes,
0.8 kilometer south of intersection of Highway 250 and
Highway 1, then 25 feet west in a pangolagrass field.
Ap-0 to 8 inches, dark brown (7.5YR 4/4) clay; weak fine subangular
blocky structure; friable, slightly sticky, slightly plastic; many fine
roots; few fine dark concretions; few fine pores; few krotovinas;
very strongly acid; clear smooth boundary.
B21t-8 to 15 inches, yellowish red (5YR 4/6) clay; moderate fine suban-
gular blocky structure; firm, slightly sticky, slightly plastic; many
fine roots; common dead dark roots; few krotovinas; few fine pores;
very strongly acid; gradual smooth boundary.
B22t-15 to 30 inches, yellowish red (5YR 4/8) clay; moderate medium
subangular blocky structure; firm, slightly sticky, slightly plastic;
common dead roots; common patchy clay films; few pores; few fine
roots; few fine weathered rock fragments; very strongly acid;
gradual smooth boundary.
B23t-30 to 43 inches, yellowish red (5YR 4/8) clay; weak fine subangu-
lar blocky structure; friable, slightly sticky, slightly plastic; few
dead roots; few pores; few weathered rock fragments; few patchy
clay films on ped surfaces; very strongly acid; gradual smooth boun-
dary.
B24t-43 to 60 inches, yellowish red (5YR 4/8) clay; weak fine subangu-
lar blocky structure; friable, slightly sticky, slightly plastic; common
fine dark stains; patchy clay films, very strongly acid.
The solum is more than 60 inches thick. Reaction throughout is
strongly acid to very strongly acid.
The A horizon has hue of 7.5YR or 5YR, value of 3 or 4, and chroma
of 3 or 4.
The B2t horizon has hue of 5YR and 2.5YR, value of 4 to 6, and
chroma of 6 to 8. It has weak to moderate fine and medium subangular
blocky structure.

Aibonito series
The Aibonito series consists of clayey, oxidic,
isohyperthermic Orthoxic Tropohumults. These soils are
deep, well drained, and have a B2 horizon of strong
brown clay. They formed in residuum of volcanic rocks.
The Aibonito soils are on side slopes and ridgetops of vol-
canic uplands. Slopes range from 12 to 40 percent, but are
dominantly 20 to 40 percent. The mean annual precipita-
tion is 90 inches, and the mean annual temperature is 75
degrees F.
The Aibonito soils are associated with the Catalina,
Comerio, and Mucara soils. They have a thinner solum
than the Catalina and Comerio soils and a thicker solum
than the Mucara soils.
Typical pedon of Aibonito clay, 20 to 40 percent slopes,
5 feet east from kilometer 6.2 of Highway 162, Aibonito,
P.R.
Ap-0 to 7 inches, dark grayish brown (10YR 4/2) clay; moderate fine
subangular blocky structure; very hard, friable, slightly sticky,
plastic; many fine roots; very strongly acid; abrupt irregular boun-
dary.
B1-7 to 11 inches, strong brown (7.5YR 5/6) clay; common fine distinct
yellowish red (5YR 4/6) mottles in ped interiors and brown (10YR
4/3) coatings on ped surfaces; extremely firm, sticky, plastic; few







SAN JUAN AREA, PUERTO RICO


fine roots restricted to the ped surfaces; few sand size grains; ex-
tremely acid; gradual wavy boundary.
B21t-ll to 22 inches, strong brown (7.5YR 5/6) clay; common fine
distinct yellowish red (5YR 4/6) mottles and brown (10YR 4/3)
coatings on surfaces of peds; strong coarse prismatic parting to
moderate medium subangular blocky structure; extremely firm,
sticky, plastic; few fine roots restricted to surfaces of peds; few
sand size grains; extremely acid; gradual wavy boundary.
B22t-22 to 32 inches, strong brown (7.5YR 5/6) clay; common fine
distinct red (2.5YR 5/6) mottles; strong coarse prismatic structure
parting to moderate medium subangular blocky; brown (10YR 4/3)
coatings on ped surfaces; extremely firm, sticky, plastic; few fine
roots; few sand size grains; extremely acid; gradual wavy boundary.
B3-32 to 43 inches, strong brown (7.5YR 5/6) clay; many medium
prominent yellowish brown (10YR 5/6) and red (2.5YR 4/6) mottles,
and few medium prominent white (10YR 8/1) mottles; weak medium
subangular blocky structure; thin patchy clay films; friable, slightly
sticky, plastic; very few fine roots; extremely acid; gradual wavy
boundary; 30 percent of this horizon is saprolite.
C1-43 to 65 inches, variegated red (2.5YR 4/6), strong brown (7.5YR
5/6), and white (10YR 8/1) clay saprolite; massive; friable, slightly
sticky, plastic; extremely acid; gradual wavy boundary.
C2-65 to 110 inches, variegated red (2.5YR 4/6), strong brown (7.5YR
5/6), and white (10YR 8/1) silty clay saprolite; massive; friable,
slightly sticky, slightly plastic; extremely acid. Rock structure is
visible. Material can be easily crushed with fingers.

The solum is 33 to 56 inches thick. Reaction throughout is very
strongly acid or extremely acid.
The A horizon has hue of 10YR and 7.5YR, value of 4, and chroma of
2 to 4.
The B2 horizon has hue of 2.5YR or 5YR, value of 4 to 6, and chroma
of 6 to 8.
The C horizons are clay and silty clay.

Almirante series
The Almirante series consists of clayey, oxidic,
isohyperthermic Plinthic Paleudults. These soils are deep,
are well drained, and have a B2 horizon of strong brown
and brownish yellow clay underlain by plinthite layers.
They formed in fine textured sediments of mixed origin.
The Almirante soils are on coastal plains and in valleys
between the limestone hills. Slopes range from 2 to 12
percent, but are dominantly 2 to 5 percent. The mean an-
nual precipitation is 65 inches, and the mean annual tem-
perature is 78 degrees F.
The Almirante soils are associated with the Bayamon,
Matanzas, Tanama, and Vega Alta soils. They have a
thicker solum than the Matanzas and the Tanama soils.
They have plinthite which the Bayamon soils lack. They
are deeper over the plinthite than the Vega Alta soils.
Typical pedon of Almirante clay, 2 to 5 percent slopes,
1 kilometer from intersection of Highway 693 and 694,
then 40 feet north, Dorado, P.R.

Ap-0 to 7 inches, dark yellowish brown (10YR 4/4) clay; weak fine sub-
angular blocky structure; friable, slightly sticky, slightly plastic;
many fine roots; many quartz grains; many fine dark concretions;
very strongly acid; clear smooth boundary.
B21t-7 to 34 inches, strong brown (7.5YR 5/6) clay; weak medium sub-
angular blocky structure; firm, slightly sticky, slightly plastic; few
patchy clay films; many quartz grains; common black stains; com-
mon fine roots; few fine pores; very strongly acid; clear smooth
boundary.
B22t-34 to 46 inches, brownish yellow (10YR 6/8) and dark red (10R
3/6) clay; weak medium subangular blocky structure; firm, sticky,


plastic; dark concretions; purple stains; few fine rock fragments;
about 8 percent by volume is plinthite; very strongly acid; gradual
smooth boundary.
B23t-46 to 60 inches, variegated brownish yellow (10YR 6/8), dark red
(10R 3/6), and light gray (5Y 7/1) clay; weak medium subangular
blocky structure; firm, sticky, plastic; about 15 percent by volume is
plinthite; very strongly acid.
The solum is more than 60 inches thick. Reaction throughout is very
strongly acid.
The A horizon has hue of 10YR, 7.5YR, or 5YR; value of 3 or 4; and
chroma of 2 to 4.
The B2t horizon has hue of 10YR, 7.5YR, or 5YR; value of 4 to 6; and
chroma of 4 to 8. It has a weak to moderate fine to medium subangular
blocky structure.

Bajura series

The Bajura series consists of fine, mixed, nonacid
isohyperthermic Vertic Tropaquepts. These soils are deep,
are poorly drained, and have a B horizon of dark gray
clay. They formed in fine textured sediments of mixed
origin. The Bajura soils are on river flood plains. Slopes
range from 0 to 2 percent. The mean annual precipitation
is 84 inches, and the mean annual temperature is 78
degrees F.
The Bajura soils are associated with the Coloso, Toa,
and Dique soils. They have more expansive clays than the
Coloso soils. They are finer textured than the Toa and the
Dique soils.
Typical pedon of Bajura clay, 0.2 miles east, 0.2 miles
north, and 25 feet east from kilometer 18.4 of Highway
165.
Ap-0 to 5 inches, dark brown (10YR 3/3) clay; weak medium subangu-
lar blocky structure; firm, slightly sticky, plastic; few fine roots;
few dead roots; few krotovinas; few root channels; few fine pebbles;
medium acid; gradual smooth boundary.
B-5 to 12 inches, dark gray (10YR 4/1) clay; mottles are common medi-
um distinct yellowish brown (10YR 5/6), few medium distinct very
dark gray (5Y 3/1), and few fine brown to dark brown (7.5YR 4/4);
weak coarse subangular blocky structure; firm, slightly sticky,
plastic; few pressure faces; few fine roots; few dead roots; few fine
pebbles; medium acid; gradual smooth boundary.
Clg-12 to 31 inches, gray to light gray (5Y 6/1) and yellowish brown
(10YR 5/6) clay; few fine greenish gray (5G 6/1) mottles; weak
coarse subangular blocky structure; firm, sticky, plastic; few peb-
bles; few dead roots; slightly acid; gradual smooth boundary.
C2g-31 to 38 inches, greenish gray (5G 6/1) clay; many medium distinct
brownish yellow (10YR 6/6) and few medium distinct bluish gray
(5B 5/1) mottles; weak coarse subangular blocky structure; firm,
sticky, plastic; neutral; gradual smooth boundary.
C3g-38 to 60 inches, greenish gray (5GY 6/1) clay; with common medi-
um prominent bluish gray (5B 5/1) and common medium distinct
olive brown (2.5Y 4/4) mottles; massive; firm, very sticky, very
plastic; few dead roots; few soft black concretions; neutral.
The solum is 12 to 20 inches thick. Reaction is medium acid to slightly
acid.
The A horizon has hue of 10YR and 2.5Y, value of 2 or 3, and chroma
of 3 or less. It has moderate medium subangular blocky structure.

Bayamon series

The Bayamon series consists of clayey, oxidic,
isohyperthermic Typic Haplorthox. These soils are deep,
are well drained, and have a B horizon of red clay. They







SAN JUAN AREA, PUERTO RICO


fine roots restricted to the ped surfaces; few sand size grains; ex-
tremely acid; gradual wavy boundary.
B21t-ll to 22 inches, strong brown (7.5YR 5/6) clay; common fine
distinct yellowish red (5YR 4/6) mottles and brown (10YR 4/3)
coatings on surfaces of peds; strong coarse prismatic parting to
moderate medium subangular blocky structure; extremely firm,
sticky, plastic; few fine roots restricted to surfaces of peds; few
sand size grains; extremely acid; gradual wavy boundary.
B22t-22 to 32 inches, strong brown (7.5YR 5/6) clay; common fine
distinct red (2.5YR 5/6) mottles; strong coarse prismatic structure
parting to moderate medium subangular blocky; brown (10YR 4/3)
coatings on ped surfaces; extremely firm, sticky, plastic; few fine
roots; few sand size grains; extremely acid; gradual wavy boundary.
B3-32 to 43 inches, strong brown (7.5YR 5/6) clay; many medium
prominent yellowish brown (10YR 5/6) and red (2.5YR 4/6) mottles,
and few medium prominent white (10YR 8/1) mottles; weak medium
subangular blocky structure; thin patchy clay films; friable, slightly
sticky, plastic; very few fine roots; extremely acid; gradual wavy
boundary; 30 percent of this horizon is saprolite.
C1-43 to 65 inches, variegated red (2.5YR 4/6), strong brown (7.5YR
5/6), and white (10YR 8/1) clay saprolite; massive; friable, slightly
sticky, plastic; extremely acid; gradual wavy boundary.
C2-65 to 110 inches, variegated red (2.5YR 4/6), strong brown (7.5YR
5/6), and white (10YR 8/1) silty clay saprolite; massive; friable,
slightly sticky, slightly plastic; extremely acid. Rock structure is
visible. Material can be easily crushed with fingers.

The solum is 33 to 56 inches thick. Reaction throughout is very
strongly acid or extremely acid.
The A horizon has hue of 10YR and 7.5YR, value of 4, and chroma of
2 to 4.
The B2 horizon has hue of 2.5YR or 5YR, value of 4 to 6, and chroma
of 6 to 8.
The C horizons are clay and silty clay.

Almirante series
The Almirante series consists of clayey, oxidic,
isohyperthermic Plinthic Paleudults. These soils are deep,
are well drained, and have a B2 horizon of strong brown
and brownish yellow clay underlain by plinthite layers.
They formed in fine textured sediments of mixed origin.
The Almirante soils are on coastal plains and in valleys
between the limestone hills. Slopes range from 2 to 12
percent, but are dominantly 2 to 5 percent. The mean an-
nual precipitation is 65 inches, and the mean annual tem-
perature is 78 degrees F.
The Almirante soils are associated with the Bayamon,
Matanzas, Tanama, and Vega Alta soils. They have a
thicker solum than the Matanzas and the Tanama soils.
They have plinthite which the Bayamon soils lack. They
are deeper over the plinthite than the Vega Alta soils.
Typical pedon of Almirante clay, 2 to 5 percent slopes,
1 kilometer from intersection of Highway 693 and 694,
then 40 feet north, Dorado, P.R.

Ap-0 to 7 inches, dark yellowish brown (10YR 4/4) clay; weak fine sub-
angular blocky structure; friable, slightly sticky, slightly plastic;
many fine roots; many quartz grains; many fine dark concretions;
very strongly acid; clear smooth boundary.
B21t-7 to 34 inches, strong brown (7.5YR 5/6) clay; weak medium sub-
angular blocky structure; firm, slightly sticky, slightly plastic; few
patchy clay films; many quartz grains; common black stains; com-
mon fine roots; few fine pores; very strongly acid; clear smooth
boundary.
B22t-34 to 46 inches, brownish yellow (10YR 6/8) and dark red (10R
3/6) clay; weak medium subangular blocky structure; firm, sticky,


plastic; dark concretions; purple stains; few fine rock fragments;
about 8 percent by volume is plinthite; very strongly acid; gradual
smooth boundary.
B23t-46 to 60 inches, variegated brownish yellow (10YR 6/8), dark red
(10R 3/6), and light gray (5Y 7/1) clay; weak medium subangular
blocky structure; firm, sticky, plastic; about 15 percent by volume is
plinthite; very strongly acid.
The solum is more than 60 inches thick. Reaction throughout is very
strongly acid.
The A horizon has hue of 10YR, 7.5YR, or 5YR; value of 3 or 4; and
chroma of 2 to 4.
The B2t horizon has hue of 10YR, 7.5YR, or 5YR; value of 4 to 6; and
chroma of 4 to 8. It has a weak to moderate fine to medium subangular
blocky structure.

Bajura series

The Bajura series consists of fine, mixed, nonacid
isohyperthermic Vertic Tropaquepts. These soils are deep,
are poorly drained, and have a B horizon of dark gray
clay. They formed in fine textured sediments of mixed
origin. The Bajura soils are on river flood plains. Slopes
range from 0 to 2 percent. The mean annual precipitation
is 84 inches, and the mean annual temperature is 78
degrees F.
The Bajura soils are associated with the Coloso, Toa,
and Dique soils. They have more expansive clays than the
Coloso soils. They are finer textured than the Toa and the
Dique soils.
Typical pedon of Bajura clay, 0.2 miles east, 0.2 miles
north, and 25 feet east from kilometer 18.4 of Highway
165.
Ap-0 to 5 inches, dark brown (10YR 3/3) clay; weak medium subangu-
lar blocky structure; firm, slightly sticky, plastic; few fine roots;
few dead roots; few krotovinas; few root channels; few fine pebbles;
medium acid; gradual smooth boundary.
B-5 to 12 inches, dark gray (10YR 4/1) clay; mottles are common medi-
um distinct yellowish brown (10YR 5/6), few medium distinct very
dark gray (5Y 3/1), and few fine brown to dark brown (7.5YR 4/4);
weak coarse subangular blocky structure; firm, slightly sticky,
plastic; few pressure faces; few fine roots; few dead roots; few fine
pebbles; medium acid; gradual smooth boundary.
Clg-12 to 31 inches, gray to light gray (5Y 6/1) and yellowish brown
(10YR 5/6) clay; few fine greenish gray (5G 6/1) mottles; weak
coarse subangular blocky structure; firm, sticky, plastic; few peb-
bles; few dead roots; slightly acid; gradual smooth boundary.
C2g-31 to 38 inches, greenish gray (5G 6/1) clay; many medium distinct
brownish yellow (10YR 6/6) and few medium distinct bluish gray
(5B 5/1) mottles; weak coarse subangular blocky structure; firm,
sticky, plastic; neutral; gradual smooth boundary.
C3g-38 to 60 inches, greenish gray (5GY 6/1) clay; with common medi-
um prominent bluish gray (5B 5/1) and common medium distinct
olive brown (2.5Y 4/4) mottles; massive; firm, very sticky, very
plastic; few dead roots; few soft black concretions; neutral.
The solum is 12 to 20 inches thick. Reaction is medium acid to slightly
acid.
The A horizon has hue of 10YR and 2.5Y, value of 2 or 3, and chroma
of 3 or less. It has moderate medium subangular blocky structure.

Bayamon series

The Bayamon series consists of clayey, oxidic,
isohyperthermic Typic Haplorthox. These soils are deep,
are well drained, and have a B horizon of red clay. They







SAN JUAN AREA, PUERTO RICO


fine roots restricted to the ped surfaces; few sand size grains; ex-
tremely acid; gradual wavy boundary.
B21t-ll to 22 inches, strong brown (7.5YR 5/6) clay; common fine
distinct yellowish red (5YR 4/6) mottles and brown (10YR 4/3)
coatings on surfaces of peds; strong coarse prismatic parting to
moderate medium subangular blocky structure; extremely firm,
sticky, plastic; few fine roots restricted to surfaces of peds; few
sand size grains; extremely acid; gradual wavy boundary.
B22t-22 to 32 inches, strong brown (7.5YR 5/6) clay; common fine
distinct red (2.5YR 5/6) mottles; strong coarse prismatic structure
parting to moderate medium subangular blocky; brown (10YR 4/3)
coatings on ped surfaces; extremely firm, sticky, plastic; few fine
roots; few sand size grains; extremely acid; gradual wavy boundary.
B3-32 to 43 inches, strong brown (7.5YR 5/6) clay; many medium
prominent yellowish brown (10YR 5/6) and red (2.5YR 4/6) mottles,
and few medium prominent white (10YR 8/1) mottles; weak medium
subangular blocky structure; thin patchy clay films; friable, slightly
sticky, plastic; very few fine roots; extremely acid; gradual wavy
boundary; 30 percent of this horizon is saprolite.
C1-43 to 65 inches, variegated red (2.5YR 4/6), strong brown (7.5YR
5/6), and white (10YR 8/1) clay saprolite; massive; friable, slightly
sticky, plastic; extremely acid; gradual wavy boundary.
C2-65 to 110 inches, variegated red (2.5YR 4/6), strong brown (7.5YR
5/6), and white (10YR 8/1) silty clay saprolite; massive; friable,
slightly sticky, slightly plastic; extremely acid. Rock structure is
visible. Material can be easily crushed with fingers.

The solum is 33 to 56 inches thick. Reaction throughout is very
strongly acid or extremely acid.
The A horizon has hue of 10YR and 7.5YR, value of 4, and chroma of
2 to 4.
The B2 horizon has hue of 2.5YR or 5YR, value of 4 to 6, and chroma
of 6 to 8.
The C horizons are clay and silty clay.

Almirante series
The Almirante series consists of clayey, oxidic,
isohyperthermic Plinthic Paleudults. These soils are deep,
are well drained, and have a B2 horizon of strong brown
and brownish yellow clay underlain by plinthite layers.
They formed in fine textured sediments of mixed origin.
The Almirante soils are on coastal plains and in valleys
between the limestone hills. Slopes range from 2 to 12
percent, but are dominantly 2 to 5 percent. The mean an-
nual precipitation is 65 inches, and the mean annual tem-
perature is 78 degrees F.
The Almirante soils are associated with the Bayamon,
Matanzas, Tanama, and Vega Alta soils. They have a
thicker solum than the Matanzas and the Tanama soils.
They have plinthite which the Bayamon soils lack. They
are deeper over the plinthite than the Vega Alta soils.
Typical pedon of Almirante clay, 2 to 5 percent slopes,
1 kilometer from intersection of Highway 693 and 694,
then 40 feet north, Dorado, P.R.

Ap-0 to 7 inches, dark yellowish brown (10YR 4/4) clay; weak fine sub-
angular blocky structure; friable, slightly sticky, slightly plastic;
many fine roots; many quartz grains; many fine dark concretions;
very strongly acid; clear smooth boundary.
B21t-7 to 34 inches, strong brown (7.5YR 5/6) clay; weak medium sub-
angular blocky structure; firm, slightly sticky, slightly plastic; few
patchy clay films; many quartz grains; common black stains; com-
mon fine roots; few fine pores; very strongly acid; clear smooth
boundary.
B22t-34 to 46 inches, brownish yellow (10YR 6/8) and dark red (10R
3/6) clay; weak medium subangular blocky structure; firm, sticky,


plastic; dark concretions; purple stains; few fine rock fragments;
about 8 percent by volume is plinthite; very strongly acid; gradual
smooth boundary.
B23t-46 to 60 inches, variegated brownish yellow (10YR 6/8), dark red
(10R 3/6), and light gray (5Y 7/1) clay; weak medium subangular
blocky structure; firm, sticky, plastic; about 15 percent by volume is
plinthite; very strongly acid.
The solum is more than 60 inches thick. Reaction throughout is very
strongly acid.
The A horizon has hue of 10YR, 7.5YR, or 5YR; value of 3 or 4; and
chroma of 2 to 4.
The B2t horizon has hue of 10YR, 7.5YR, or 5YR; value of 4 to 6; and
chroma of 4 to 8. It has a weak to moderate fine to medium subangular
blocky structure.

Bajura series

The Bajura series consists of fine, mixed, nonacid
isohyperthermic Vertic Tropaquepts. These soils are deep,
are poorly drained, and have a B horizon of dark gray
clay. They formed in fine textured sediments of mixed
origin. The Bajura soils are on river flood plains. Slopes
range from 0 to 2 percent. The mean annual precipitation
is 84 inches, and the mean annual temperature is 78
degrees F.
The Bajura soils are associated with the Coloso, Toa,
and Dique soils. They have more expansive clays than the
Coloso soils. They are finer textured than the Toa and the
Dique soils.
Typical pedon of Bajura clay, 0.2 miles east, 0.2 miles
north, and 25 feet east from kilometer 18.4 of Highway
165.
Ap-0 to 5 inches, dark brown (10YR 3/3) clay; weak medium subangu-
lar blocky structure; firm, slightly sticky, plastic; few fine roots;
few dead roots; few krotovinas; few root channels; few fine pebbles;
medium acid; gradual smooth boundary.
B-5 to 12 inches, dark gray (10YR 4/1) clay; mottles are common medi-
um distinct yellowish brown (10YR 5/6), few medium distinct very
dark gray (5Y 3/1), and few fine brown to dark brown (7.5YR 4/4);
weak coarse subangular blocky structure; firm, slightly sticky,
plastic; few pressure faces; few fine roots; few dead roots; few fine
pebbles; medium acid; gradual smooth boundary.
Clg-12 to 31 inches, gray to light gray (5Y 6/1) and yellowish brown
(10YR 5/6) clay; few fine greenish gray (5G 6/1) mottles; weak
coarse subangular blocky structure; firm, sticky, plastic; few peb-
bles; few dead roots; slightly acid; gradual smooth boundary.
C2g-31 to 38 inches, greenish gray (5G 6/1) clay; many medium distinct
brownish yellow (10YR 6/6) and few medium distinct bluish gray
(5B 5/1) mottles; weak coarse subangular blocky structure; firm,
sticky, plastic; neutral; gradual smooth boundary.
C3g-38 to 60 inches, greenish gray (5GY 6/1) clay; with common medi-
um prominent bluish gray (5B 5/1) and common medium distinct
olive brown (2.5Y 4/4) mottles; massive; firm, very sticky, very
plastic; few dead roots; few soft black concretions; neutral.
The solum is 12 to 20 inches thick. Reaction is medium acid to slightly
acid.
The A horizon has hue of 10YR and 2.5Y, value of 2 or 3, and chroma
of 3 or less. It has moderate medium subangular blocky structure.

Bayamon series

The Bayamon series consists of clayey, oxidic,
isohyperthermic Typic Haplorthox. These soils are deep,
are well drained, and have a B horizon of red clay. They







SOIL SURVEY


formed in fine textured sediments of mixed origin. The
Bayamon soils are on stable coastal plains and in valleys
between limestone hills. Slopes range from 2 to 5 percent.
The mean annual precipitation is 65 inches, and the mean
annual temperature is 78 degrees F.
The Bayamon soils are associated with the Almirante,
Matanzas, and Vega Alta soils. They have a thicker solum
than the Matanzas and Vega Alta soils. They lack the
plinthic horizons of the Almirante and Vega Alta soils.
Typical pedon of Bayamon clay, 2 to 5 percent slopes,
80 feet east of shed and 50 feet north of junction of dirt
roads, 0.4 miles west from farm entrance on dirt road.
A.S.A. farm at Finca Monterrey, Bo. Higuillar, Dorado,
P.R.

Ap-0 to 8 inches, dark reddish brown (2.5YR 3/4) clay; moderate fine
granular structure; friable, slightly sticky, slightly plastic; common
fine roots; few fine iron concretions; common fine sand size quartz
grains; very strongly acid; clear smooth boundary.
B21-8 to 27 inches, weak red (10R 4/4) clay; weak coarse subangular
blocky structure parting to moderate fine angular blocky structure;
firm, slightly sticky, slightly plastic; few fine roots; few fine oxide
concretions; common fine quartz grains; common fine pores; black
coatings on old root channels; very strongly acid; gradual smooth
boundary.
B22-27 to 42 inches, red (10R 4/6) clay; massive in place, parting to
weak very fine subangular blocky structure; friable, slightly sticky,
slightly plastic; few fine pores; few fine sand size quartz grains; few
fine black specks; very strongly acid; gradual smooth boundary.
B23-42 to 66 inches, red (10R 4/6) clay; massive in place, parting to
weak very fine subangular blocky structure; very friable, slightly
sticky, slightly plastic; few sand size quartz grains; few very fine
black specks; few fine pores; yellow waxy coatings on ped surfaces
and root channels; very strongly acid.
The solum is more than 60 inches thick. Reaction is very strongly acid.
The A horizon has hue of 5YR, 2.5YR, or 10R; value of 3 or 4; arid
chroma of 3 or 4.
The B2 horizon has hue of 2.5YR or 10R, value of 4 to 6, and chroma
of 3 to 8. It is massive or has weak coarse and medium subangular
blocky structure which parts readily into weak and moderate fine and
medium angular and subangular blocky structure.

Caguabo series

The Caguabo series consists of loamy-skeletal, mixed,
isohyperthermic Lithic Eutropepts. These soils are shal-
low, are well drained, and have an AC horizon of brown
very gravelly clay loam. They formed in residuum of vol-
canic rocks. The Caguabo soils are on side slopes and
ridgetops of strongly dissected uplands. Slopes range
from 20 to 60 percent, but are dominantly 40 to 60 per-
cent. The mean annual precipitation is 80 inches, and the
mean annual temperature is 76 degrees F.
The Caguabo soils are associated with the Mucara,
Morado, and Sabana soils. They have a thinner solum than
the Mucara and Morado soils. They are less acid than the
Sabana soils.
Typical pedon of Caguabo clay loam, 20 to 40 percent
slopes, 300 feet east and 400 feet south of the tobacco
drying barn which is approximately 1000 feet west of sta-
tion headquarters, Gurabo Experiment Station.

Ap-0 to 4 inches, dark grayish brown (10YR 4/2) clay loam; weak fine
granular structure; slightly hard, friable, nonsticky, slightly plastic;


common fine volcanic rock fragments, common fine roots; slightly
acid; clear smooth boundary.
AC-4 to 10 inches, brown (10YR 4/3) very gravelly clay loam; massive
in place, parting to weak fine granular structure; friable, slightly
sticky, slightly plastic; more than 50 percent by volume fine volcanic
fragments; few fine roots; slightly acid; clear smooth boundary.
C-10 to 16 inches, mixture of weathered and partially weathered vol-
canic rock fragments that can be penetrated by spade.
R-16 inches, consolidated rock.
The solum is 8 to 16 inches thick. Reaction throughout is slightly acid.
The A horizon has hue of 10YR or 2.5Y, value of 3 or 4, and chroma
of 2 to 4.
The AC horizon has hue of 10YR or 7.5YR, value of 3 to 5, and
chroma of 3 or 4.

Candelero series

The Candelero series consists of fine-loamy, mixed,
isohyperthermic Aeric Tropaqualfs. These soils are deep,
are somewhat poorly drained, and have a B2g horizon of
dark gray or very dark gray sandy clay loam. They
formed in moderately fine textured sediments high in
quartz, feldspar, and hornblende minerals derived from
granitic rocks.
The Candelero soils are on terraces, alluvial fans, and
foot slopes. Slopes range from 2 to 5 percent. The mean
annual precipitation is 87 inches, and the mean annual
temperature is 77 degrees F.
The Candelero soils are associated with the Humacao
and Cayagua soils. They have a thicker solum than the
Humacao and Cayagua soils.
Typical pedon of Candelero loam, 0.1 mile northeast
from kilometer 0.6 of Highway 183, then 450 feet
northwest from a farm road, San Lorenzo, P.R.

Ap-0 to 6 inches, dark grayish brown (10YR 4/2) loam; few fine dark
gray (10YR 4/1) mottles; weak fine subangular blocky structure
parting to granular; friable; nonsticky, slightly plastic; common fine
roots; common fine quartz grains; common fine black concretions;
very strongly acid; clear smooth boundary.
B1-6 to 11 inches, dark brown (10YR 4/3) and dark gray (10YR 4/1),
sandy clay loam; few fine yellowish red (5YR 4/6) and dark yel-
lowish brown (10YR 4/4) mottles; weak fine subangular blocky
structure; friable, nonsticky, slightly plastic; common fine roots;
many fine quartz crystals; common fine black concretions; very
strongly acid; clear smooth boundary.
B21tg-11 to 20 inches, dark gray (10YR 4/1) sandy clay loam; many
medium distinct yellowish brown (10YR 5/8) and few fine faint gray
(N 5/0) mottles; weak medium and coarse subangular blocky struc-
ture; firm, slightly sticky, plastic; few fine roots; many quartz
grains; common soft black concretions; strongly acid; gradual
smooth boundary.
B22tg-20 to 35 inches, very dark gray (10YR 3/1) sandy clay loam;
common medium distinct greenish gray (5GY 6/1) and brownish yel-
low (10YR 6/6) mottles; massive; firm, slightly sticky, plastic; few
fine roots; many quartz grains; few fine dark minerals; common
dark minerals; common dark stains due to dead roots; strongly acid;
gradual smooth boundary.
B31g-35 to 49 inches, brownish yellow (10YR 6/8) sandy clay; mottles
are common medium distinct dark gray (5Y 4/1) and few fine
greenish gray (5G 5/1) and light brownish gray (10YR 6/2); massive;
firm, slightly sticky, plastic; few fine quartz grains; few dark soft
concretions; few dark stains; medium acid; gradual smooth bounda-
ry.
B32g-49 to 60 inches, yellowish brown (10YR 5/4) sandy clay; mottles
are many fine distinct gray (5Y 6/1) and few fine yellowish red
(5YR 4/6) and dark reddish brown (2.5YR 3/4); firm, slightly sticky,







SOIL SURVEY


formed in fine textured sediments of mixed origin. The
Bayamon soils are on stable coastal plains and in valleys
between limestone hills. Slopes range from 2 to 5 percent.
The mean annual precipitation is 65 inches, and the mean
annual temperature is 78 degrees F.
The Bayamon soils are associated with the Almirante,
Matanzas, and Vega Alta soils. They have a thicker solum
than the Matanzas and Vega Alta soils. They lack the
plinthic horizons of the Almirante and Vega Alta soils.
Typical pedon of Bayamon clay, 2 to 5 percent slopes,
80 feet east of shed and 50 feet north of junction of dirt
roads, 0.4 miles west from farm entrance on dirt road.
A.S.A. farm at Finca Monterrey, Bo. Higuillar, Dorado,
P.R.

Ap-0 to 8 inches, dark reddish brown (2.5YR 3/4) clay; moderate fine
granular structure; friable, slightly sticky, slightly plastic; common
fine roots; few fine iron concretions; common fine sand size quartz
grains; very strongly acid; clear smooth boundary.
B21-8 to 27 inches, weak red (10R 4/4) clay; weak coarse subangular
blocky structure parting to moderate fine angular blocky structure;
firm, slightly sticky, slightly plastic; few fine roots; few fine oxide
concretions; common fine quartz grains; common fine pores; black
coatings on old root channels; very strongly acid; gradual smooth
boundary.
B22-27 to 42 inches, red (10R 4/6) clay; massive in place, parting to
weak very fine subangular blocky structure; friable, slightly sticky,
slightly plastic; few fine pores; few fine sand size quartz grains; few
fine black specks; very strongly acid; gradual smooth boundary.
B23-42 to 66 inches, red (10R 4/6) clay; massive in place, parting to
weak very fine subangular blocky structure; very friable, slightly
sticky, slightly plastic; few sand size quartz grains; few very fine
black specks; few fine pores; yellow waxy coatings on ped surfaces
and root channels; very strongly acid.
The solum is more than 60 inches thick. Reaction is very strongly acid.
The A horizon has hue of 5YR, 2.5YR, or 10R; value of 3 or 4; arid
chroma of 3 or 4.
The B2 horizon has hue of 2.5YR or 10R, value of 4 to 6, and chroma
of 3 to 8. It is massive or has weak coarse and medium subangular
blocky structure which parts readily into weak and moderate fine and
medium angular and subangular blocky structure.

Caguabo series

The Caguabo series consists of loamy-skeletal, mixed,
isohyperthermic Lithic Eutropepts. These soils are shal-
low, are well drained, and have an AC horizon of brown
very gravelly clay loam. They formed in residuum of vol-
canic rocks. The Caguabo soils are on side slopes and
ridgetops of strongly dissected uplands. Slopes range
from 20 to 60 percent, but are dominantly 40 to 60 per-
cent. The mean annual precipitation is 80 inches, and the
mean annual temperature is 76 degrees F.
The Caguabo soils are associated with the Mucara,
Morado, and Sabana soils. They have a thinner solum than
the Mucara and Morado soils. They are less acid than the
Sabana soils.
Typical pedon of Caguabo clay loam, 20 to 40 percent
slopes, 300 feet east and 400 feet south of the tobacco
drying barn which is approximately 1000 feet west of sta-
tion headquarters, Gurabo Experiment Station.

Ap-0 to 4 inches, dark grayish brown (10YR 4/2) clay loam; weak fine
granular structure; slightly hard, friable, nonsticky, slightly plastic;


common fine volcanic rock fragments, common fine roots; slightly
acid; clear smooth boundary.
AC-4 to 10 inches, brown (10YR 4/3) very gravelly clay loam; massive
in place, parting to weak fine granular structure; friable, slightly
sticky, slightly plastic; more than 50 percent by volume fine volcanic
fragments; few fine roots; slightly acid; clear smooth boundary.
C-10 to 16 inches, mixture of weathered and partially weathered vol-
canic rock fragments that can be penetrated by spade.
R-16 inches, consolidated rock.
The solum is 8 to 16 inches thick. Reaction throughout is slightly acid.
The A horizon has hue of 10YR or 2.5Y, value of 3 or 4, and chroma
of 2 to 4.
The AC horizon has hue of 10YR or 7.5YR, value of 3 to 5, and
chroma of 3 or 4.

Candelero series

The Candelero series consists of fine-loamy, mixed,
isohyperthermic Aeric Tropaqualfs. These soils are deep,
are somewhat poorly drained, and have a B2g horizon of
dark gray or very dark gray sandy clay loam. They
formed in moderately fine textured sediments high in
quartz, feldspar, and hornblende minerals derived from
granitic rocks.
The Candelero soils are on terraces, alluvial fans, and
foot slopes. Slopes range from 2 to 5 percent. The mean
annual precipitation is 87 inches, and the mean annual
temperature is 77 degrees F.
The Candelero soils are associated with the Humacao
and Cayagua soils. They have a thicker solum than the
Humacao and Cayagua soils.
Typical pedon of Candelero loam, 0.1 mile northeast
from kilometer 0.6 of Highway 183, then 450 feet
northwest from a farm road, San Lorenzo, P.R.

Ap-0 to 6 inches, dark grayish brown (10YR 4/2) loam; few fine dark
gray (10YR 4/1) mottles; weak fine subangular blocky structure
parting to granular; friable; nonsticky, slightly plastic; common fine
roots; common fine quartz grains; common fine black concretions;
very strongly acid; clear smooth boundary.
B1-6 to 11 inches, dark brown (10YR 4/3) and dark gray (10YR 4/1),
sandy clay loam; few fine yellowish red (5YR 4/6) and dark yel-
lowish brown (10YR 4/4) mottles; weak fine subangular blocky
structure; friable, nonsticky, slightly plastic; common fine roots;
many fine quartz crystals; common fine black concretions; very
strongly acid; clear smooth boundary.
B21tg-11 to 20 inches, dark gray (10YR 4/1) sandy clay loam; many
medium distinct yellowish brown (10YR 5/8) and few fine faint gray
(N 5/0) mottles; weak medium and coarse subangular blocky struc-
ture; firm, slightly sticky, plastic; few fine roots; many quartz
grains; common soft black concretions; strongly acid; gradual
smooth boundary.
B22tg-20 to 35 inches, very dark gray (10YR 3/1) sandy clay loam;
common medium distinct greenish gray (5GY 6/1) and brownish yel-
low (10YR 6/6) mottles; massive; firm, slightly sticky, plastic; few
fine roots; many quartz grains; few fine dark minerals; common
dark minerals; common dark stains due to dead roots; strongly acid;
gradual smooth boundary.
B31g-35 to 49 inches, brownish yellow (10YR 6/8) sandy clay; mottles
are common medium distinct dark gray (5Y 4/1) and few fine
greenish gray (5G 5/1) and light brownish gray (10YR 6/2); massive;
firm, slightly sticky, plastic; few fine quartz grains; few dark soft
concretions; few dark stains; medium acid; gradual smooth bounda-
ry.
B32g-49 to 60 inches, yellowish brown (10YR 5/4) sandy clay; mottles
are many fine distinct gray (5Y 6/1) and few fine yellowish red
(5YR 4/6) and dark reddish brown (2.5YR 3/4); firm, slightly sticky,







SAN JUAN AREA, PUERTO RICO


plastic; few fine quartz grains; few sand lenses; few soft black
concretions; medium acid.

The solum is more than 60 inches thick. Reaction throughout is medi-
um acid to very strongly acid.
The A horizon has hue of 10YR, value of 3 or 4, and chroma of 2 or 3.
The B2t horizon has hue of 10YR, value of 3 or 4, and chroma of 1 to
3. It has weak medium and coarse subangular blocky structure or is
massive.

Catalina series

The Catalina series consists of clayey, oxidic,
isohyperthermic Tropeptic Haplorthox. These soils are
deep, are well drained, and have a B2 horizon of dark red-
dish brown and reddish brown clay. They formed in fine
textured residuum of volcanic rocks. The Catalina soils
are on side slopes and hilltops. Slopes range from 4 to 12
percent. The mean annual precipitation is 85 inches, and
the mean annual temperature is 75 degrees F.
The Catalina soils are associated with the Humatas,
Daguey, and Consumo soils. They have a thicker solum
than the Daguey soils and have a thicker B2 horizon than
the Humatas and Consumo soils.
Typical pedon of Catalina clay, 4 to 12 percent slopes,
45 feet east of field road and 470 feet south of house at
kilometer 8.8 of Highway 152, Barranquitas, P.R.

Ap-- to 6 inches, dark reddish brown (5YR 3/3) clay, few fine distinct
reddish brown (2.5YR 4/4) pockets; weak fine granular structure;
friable, slightly sticky, slightly plastic; many fine roots; many sand
size particles; few fine pieces of charcoal; medium acid; abrupt
smooth boundary.
B21-6 to 20 inches, dark reddish brown (2.5YR 3/4) clay; moderate
medium subangular blocky structure; firm, slightly sticky, slightly
plastic; common fine roots; common fine pores; many soft black
sand size particles; very strongly acid; clear smooth boundary.
B22-20 to 34 inches, reddish brown (2.5YR 5/4) clay; few reddish
brown (2.5YR 4/4) ped faces; weak fine subangular blocky struc-
ture; firm, slightly sticky, plastic; few fine roots; few fine pores;
few fine sand size particles; few pressure faces; very strongly acid;
clear smooth boundary.
B23-34 to 84 inches, dark reddish brown (2.5YR 3/4) clay; weak fine
angular blocky structure; firm, slightly sticky, plastic; few fine
pores; common pressure faces; strongly acid; gradual wavy bounda-
ry.
B24-84 to 99 inches, variegated dusky red (10R 3/4), dark reddish
brown (2.5YR 3/4), and strong brown (7.5YR 5/8) clay; few dark
gray and white splotches; massive; firm, plastic; very strongly acid.
The solum is more than 60 inches thick. Reaction throughout is medi-
um acid to very strongly acid.
The A horizon has hue of 5YR or 2.5YR, value of 3 or 4, and chroma
of 3 or 4.
The B2 horizon has hue of 2.5YR or 10R, value of 3 or 4, and chroma
of 4 to 8. It has weak to moderate fine or medium subangular blocky
structure or is massive.

Catano series

The Catano series consists of carbonatic, isohyperther-
mic Typic Troposamments. These soils are deep and ex-
cessively drained. They have A horizons of very dark
brown sand and C horizons of dark brown and dark gray-
ish brown sand. They formed in quartz sand, shell frag-
ments, and miscellaneous volcanic rocks. The Catano soils
are on coastal plains adjacent to the sea. Slopes range


from 0 to 2 percent. The mean annual precipitation is 76
inches, and the mean annual temperature is 78 degrees F.
The Catano soils are associated with the Durados soils.
They are coarser textured than the Durados soils.
Typical pedon of Catano loamy sand, 50 feet north of
electrical transformers on east end of Punta Salinas,
Catano, P.R.
A-0 to 7 inches, very dark grayish brown (10YR 3/2) loamy sand; sin-
gle grain; loose, nonsticky, nonplastic; many fine roots; violent effer-
vescence; clear smooth boundary.
AC-7 to 23 inches, dark brown (10YR 4/3) sand; single grain; loose;
nonsticky, nonplastic; common fine roots; violent effervescence;
clear smooth boundary.
C-23 to 58 inches; dark grayish brown (10YR 4/2) sand; single grain;
loose, nonsticky, nonplastic; many fine shell fragments; violent ef-
fervescence.
Effervescence with dilute HCL ranges from slight to violent.
The A horizon has hue of 10YR and value and chroma of 2 or 3.

Cayagua series

The Cayagua series consists of fine, mixed,
isohyperthermic Aeric Tropaqualfs. These soils are deep,
are somewhat poorly drained, and have a B2tg horizon of
light olive gray clay. They formed in residuum of coarse
textured plutonic rocks. The Cayagua soils are on foot
slopes and side slopes. Slopes range from 5 to 12 percent.
The mean annual precipitation is 80 inches, and the mean
annual temperature is 78 degrees F.
The Cayagua soils are associated with the Candelero
and Humacao soils. They have a thinner solum than the
Candelero soils and finer textured B horizons than the
Humacao soils.
Typical pedon of Cayagua sandy loam, 70 feet north
from kilometer 13.75 of Highway 183, San Lorenzo, P.R.

Ap-0 to 8 inches, dark grayish brown (10YR 4/2) sandy loam; few fine
dark gray (5Y 4/1) mottles; weak fine subangular blocky structure;
friable, nonsticky, nonplastic; common fine roots; common fine
quartz grains; few fine black concretions; very strongly acid; abrupt
smooth boundary.
B21t-8 to 16 inches, yellowish brown (10YR 5/4) clay; mottles are com-
mon fine prominent dark gray (5Y 4/1), yellowish red (5YR 5/8),
and red (2.5YR 4/8); firm, slightly sticky, plastic; few fine roots; few
patchy clay films; common fine quartz grains; common dark stains
in root channels; few soft black concretions; very strongly acid;
clear smooth boundary.
B22tg-16 to 22 inches, light olive gray (5Y 6/2) clay; common fine
distinct yellowish brown (10YR 5/4) and strong brown (7.5YR 5/8)
mottles; and few fine red (2.5YR 5/8) and greenish gray (5G 6/1)
mottles; weak coarse subangular blocky structure; firm, slightly
sticky, plastic; few fine roots; common fine quartz grains; few soft
black concretions; very strongly acid; clear smooth boundary.
B3g-22 to 32 inches, light olive gray (5Y 6/2) sandy clay loam; common
medium prominent yellowish brown (10YR 5/8) mottles, and few
fine greenish gray (5BG 6/1) and light gray (2.5Y 7/2) mottles; mas-
sive; firm, slightly sticky, slightly plastic; common fine quartz
grains; few soft black concretions; strongly acid; gradual smooth
boundary.
C-32 to 43 inches, mixed yellowish brown (10YR 5/4 and 5/8), white
(2.5Y 8/2), and gray (5Y 5/1) sandy clay loam saprolite; massive; fri-
able, nonsticky, nonplastic; common fine quartz grains; common fine
dark minerals; horizon consists of 80 percent saprolite; strongly
acid.







SAN JUAN AREA, PUERTO RICO


plastic; few fine quartz grains; few sand lenses; few soft black
concretions; medium acid.

The solum is more than 60 inches thick. Reaction throughout is medi-
um acid to very strongly acid.
The A horizon has hue of 10YR, value of 3 or 4, and chroma of 2 or 3.
The B2t horizon has hue of 10YR, value of 3 or 4, and chroma of 1 to
3. It has weak medium and coarse subangular blocky structure or is
massive.

Catalina series

The Catalina series consists of clayey, oxidic,
isohyperthermic Tropeptic Haplorthox. These soils are
deep, are well drained, and have a B2 horizon of dark red-
dish brown and reddish brown clay. They formed in fine
textured residuum of volcanic rocks. The Catalina soils
are on side slopes and hilltops. Slopes range from 4 to 12
percent. The mean annual precipitation is 85 inches, and
the mean annual temperature is 75 degrees F.
The Catalina soils are associated with the Humatas,
Daguey, and Consumo soils. They have a thicker solum
than the Daguey soils and have a thicker B2 horizon than
the Humatas and Consumo soils.
Typical pedon of Catalina clay, 4 to 12 percent slopes,
45 feet east of field road and 470 feet south of house at
kilometer 8.8 of Highway 152, Barranquitas, P.R.

Ap-- to 6 inches, dark reddish brown (5YR 3/3) clay, few fine distinct
reddish brown (2.5YR 4/4) pockets; weak fine granular structure;
friable, slightly sticky, slightly plastic; many fine roots; many sand
size particles; few fine pieces of charcoal; medium acid; abrupt
smooth boundary.
B21-6 to 20 inches, dark reddish brown (2.5YR 3/4) clay; moderate
medium subangular blocky structure; firm, slightly sticky, slightly
plastic; common fine roots; common fine pores; many soft black
sand size particles; very strongly acid; clear smooth boundary.
B22-20 to 34 inches, reddish brown (2.5YR 5/4) clay; few reddish
brown (2.5YR 4/4) ped faces; weak fine subangular blocky struc-
ture; firm, slightly sticky, plastic; few fine roots; few fine pores;
few fine sand size particles; few pressure faces; very strongly acid;
clear smooth boundary.
B23-34 to 84 inches, dark reddish brown (2.5YR 3/4) clay; weak fine
angular blocky structure; firm, slightly sticky, plastic; few fine
pores; common pressure faces; strongly acid; gradual wavy bounda-
ry.
B24-84 to 99 inches, variegated dusky red (10R 3/4), dark reddish
brown (2.5YR 3/4), and strong brown (7.5YR 5/8) clay; few dark
gray and white splotches; massive; firm, plastic; very strongly acid.
The solum is more than 60 inches thick. Reaction throughout is medi-
um acid to very strongly acid.
The A horizon has hue of 5YR or 2.5YR, value of 3 or 4, and chroma
of 3 or 4.
The B2 horizon has hue of 2.5YR or 10R, value of 3 or 4, and chroma
of 4 to 8. It has weak to moderate fine or medium subangular blocky
structure or is massive.

Catano series

The Catano series consists of carbonatic, isohyperther-
mic Typic Troposamments. These soils are deep and ex-
cessively drained. They have A horizons of very dark
brown sand and C horizons of dark brown and dark gray-
ish brown sand. They formed in quartz sand, shell frag-
ments, and miscellaneous volcanic rocks. The Catano soils
are on coastal plains adjacent to the sea. Slopes range


from 0 to 2 percent. The mean annual precipitation is 76
inches, and the mean annual temperature is 78 degrees F.
The Catano soils are associated with the Durados soils.
They are coarser textured than the Durados soils.
Typical pedon of Catano loamy sand, 50 feet north of
electrical transformers on east end of Punta Salinas,
Catano, P.R.
A-0 to 7 inches, very dark grayish brown (10YR 3/2) loamy sand; sin-
gle grain; loose, nonsticky, nonplastic; many fine roots; violent effer-
vescence; clear smooth boundary.
AC-7 to 23 inches, dark brown (10YR 4/3) sand; single grain; loose;
nonsticky, nonplastic; common fine roots; violent effervescence;
clear smooth boundary.
C-23 to 58 inches; dark grayish brown (10YR 4/2) sand; single grain;
loose, nonsticky, nonplastic; many fine shell fragments; violent ef-
fervescence.
Effervescence with dilute HCL ranges from slight to violent.
The A horizon has hue of 10YR and value and chroma of 2 or 3.

Cayagua series

The Cayagua series consists of fine, mixed,
isohyperthermic Aeric Tropaqualfs. These soils are deep,
are somewhat poorly drained, and have a B2tg horizon of
light olive gray clay. They formed in residuum of coarse
textured plutonic rocks. The Cayagua soils are on foot
slopes and side slopes. Slopes range from 5 to 12 percent.
The mean annual precipitation is 80 inches, and the mean
annual temperature is 78 degrees F.
The Cayagua soils are associated with the Candelero
and Humacao soils. They have a thinner solum than the
Candelero soils and finer textured B horizons than the
Humacao soils.
Typical pedon of Cayagua sandy loam, 70 feet north
from kilometer 13.75 of Highway 183, San Lorenzo, P.R.

Ap-0 to 8 inches, dark grayish brown (10YR 4/2) sandy loam; few fine
dark gray (5Y 4/1) mottles; weak fine subangular blocky structure;
friable, nonsticky, nonplastic; common fine roots; common fine
quartz grains; few fine black concretions; very strongly acid; abrupt
smooth boundary.
B21t-8 to 16 inches, yellowish brown (10YR 5/4) clay; mottles are com-
mon fine prominent dark gray (5Y 4/1), yellowish red (5YR 5/8),
and red (2.5YR 4/8); firm, slightly sticky, plastic; few fine roots; few
patchy clay films; common fine quartz grains; common dark stains
in root channels; few soft black concretions; very strongly acid;
clear smooth boundary.
B22tg-16 to 22 inches, light olive gray (5Y 6/2) clay; common fine
distinct yellowish brown (10YR 5/4) and strong brown (7.5YR 5/8)
mottles; and few fine red (2.5YR 5/8) and greenish gray (5G 6/1)
mottles; weak coarse subangular blocky structure; firm, slightly
sticky, plastic; few fine roots; common fine quartz grains; few soft
black concretions; very strongly acid; clear smooth boundary.
B3g-22 to 32 inches, light olive gray (5Y 6/2) sandy clay loam; common
medium prominent yellowish brown (10YR 5/8) mottles, and few
fine greenish gray (5BG 6/1) and light gray (2.5Y 7/2) mottles; mas-
sive; firm, slightly sticky, slightly plastic; common fine quartz
grains; few soft black concretions; strongly acid; gradual smooth
boundary.
C-32 to 43 inches, mixed yellowish brown (10YR 5/4 and 5/8), white
(2.5Y 8/2), and gray (5Y 5/1) sandy clay loam saprolite; massive; fri-
able, nonsticky, nonplastic; common fine quartz grains; common fine
dark minerals; horizon consists of 80 percent saprolite; strongly
acid.







SAN JUAN AREA, PUERTO RICO


plastic; few fine quartz grains; few sand lenses; few soft black
concretions; medium acid.

The solum is more than 60 inches thick. Reaction throughout is medi-
um acid to very strongly acid.
The A horizon has hue of 10YR, value of 3 or 4, and chroma of 2 or 3.
The B2t horizon has hue of 10YR, value of 3 or 4, and chroma of 1 to
3. It has weak medium and coarse subangular blocky structure or is
massive.

Catalina series

The Catalina series consists of clayey, oxidic,
isohyperthermic Tropeptic Haplorthox. These soils are
deep, are well drained, and have a B2 horizon of dark red-
dish brown and reddish brown clay. They formed in fine
textured residuum of volcanic rocks. The Catalina soils
are on side slopes and hilltops. Slopes range from 4 to 12
percent. The mean annual precipitation is 85 inches, and
the mean annual temperature is 75 degrees F.
The Catalina soils are associated with the Humatas,
Daguey, and Consumo soils. They have a thicker solum
than the Daguey soils and have a thicker B2 horizon than
the Humatas and Consumo soils.
Typical pedon of Catalina clay, 4 to 12 percent slopes,
45 feet east of field road and 470 feet south of house at
kilometer 8.8 of Highway 152, Barranquitas, P.R.

Ap-- to 6 inches, dark reddish brown (5YR 3/3) clay, few fine distinct
reddish brown (2.5YR 4/4) pockets; weak fine granular structure;
friable, slightly sticky, slightly plastic; many fine roots; many sand
size particles; few fine pieces of charcoal; medium acid; abrupt
smooth boundary.
B21-6 to 20 inches, dark reddish brown (2.5YR 3/4) clay; moderate
medium subangular blocky structure; firm, slightly sticky, slightly
plastic; common fine roots; common fine pores; many soft black
sand size particles; very strongly acid; clear smooth boundary.
B22-20 to 34 inches, reddish brown (2.5YR 5/4) clay; few reddish
brown (2.5YR 4/4) ped faces; weak fine subangular blocky struc-
ture; firm, slightly sticky, plastic; few fine roots; few fine pores;
few fine sand size particles; few pressure faces; very strongly acid;
clear smooth boundary.
B23-34 to 84 inches, dark reddish brown (2.5YR 3/4) clay; weak fine
angular blocky structure; firm, slightly sticky, plastic; few fine
pores; common pressure faces; strongly acid; gradual wavy bounda-
ry.
B24-84 to 99 inches, variegated dusky red (10R 3/4), dark reddish
brown (2.5YR 3/4), and strong brown (7.5YR 5/8) clay; few dark
gray and white splotches; massive; firm, plastic; very strongly acid.
The solum is more than 60 inches thick. Reaction throughout is medi-
um acid to very strongly acid.
The A horizon has hue of 5YR or 2.5YR, value of 3 or 4, and chroma
of 3 or 4.
The B2 horizon has hue of 2.5YR or 10R, value of 3 or 4, and chroma
of 4 to 8. It has weak to moderate fine or medium subangular blocky
structure or is massive.

Catano series

The Catano series consists of carbonatic, isohyperther-
mic Typic Troposamments. These soils are deep and ex-
cessively drained. They have A horizons of very dark
brown sand and C horizons of dark brown and dark gray-
ish brown sand. They formed in quartz sand, shell frag-
ments, and miscellaneous volcanic rocks. The Catano soils
are on coastal plains adjacent to the sea. Slopes range


from 0 to 2 percent. The mean annual precipitation is 76
inches, and the mean annual temperature is 78 degrees F.
The Catano soils are associated with the Durados soils.
They are coarser textured than the Durados soils.
Typical pedon of Catano loamy sand, 50 feet north of
electrical transformers on east end of Punta Salinas,
Catano, P.R.
A-0 to 7 inches, very dark grayish brown (10YR 3/2) loamy sand; sin-
gle grain; loose, nonsticky, nonplastic; many fine roots; violent effer-
vescence; clear smooth boundary.
AC-7 to 23 inches, dark brown (10YR 4/3) sand; single grain; loose;
nonsticky, nonplastic; common fine roots; violent effervescence;
clear smooth boundary.
C-23 to 58 inches; dark grayish brown (10YR 4/2) sand; single grain;
loose, nonsticky, nonplastic; many fine shell fragments; violent ef-
fervescence.
Effervescence with dilute HCL ranges from slight to violent.
The A horizon has hue of 10YR and value and chroma of 2 or 3.

Cayagua series

The Cayagua series consists of fine, mixed,
isohyperthermic Aeric Tropaqualfs. These soils are deep,
are somewhat poorly drained, and have a B2tg horizon of
light olive gray clay. They formed in residuum of coarse
textured plutonic rocks. The Cayagua soils are on foot
slopes and side slopes. Slopes range from 5 to 12 percent.
The mean annual precipitation is 80 inches, and the mean
annual temperature is 78 degrees F.
The Cayagua soils are associated with the Candelero
and Humacao soils. They have a thinner solum than the
Candelero soils and finer textured B horizons than the
Humacao soils.
Typical pedon of Cayagua sandy loam, 70 feet north
from kilometer 13.75 of Highway 183, San Lorenzo, P.R.

Ap-0 to 8 inches, dark grayish brown (10YR 4/2) sandy loam; few fine
dark gray (5Y 4/1) mottles; weak fine subangular blocky structure;
friable, nonsticky, nonplastic; common fine roots; common fine
quartz grains; few fine black concretions; very strongly acid; abrupt
smooth boundary.
B21t-8 to 16 inches, yellowish brown (10YR 5/4) clay; mottles are com-
mon fine prominent dark gray (5Y 4/1), yellowish red (5YR 5/8),
and red (2.5YR 4/8); firm, slightly sticky, plastic; few fine roots; few
patchy clay films; common fine quartz grains; common dark stains
in root channels; few soft black concretions; very strongly acid;
clear smooth boundary.
B22tg-16 to 22 inches, light olive gray (5Y 6/2) clay; common fine
distinct yellowish brown (10YR 5/4) and strong brown (7.5YR 5/8)
mottles; and few fine red (2.5YR 5/8) and greenish gray (5G 6/1)
mottles; weak coarse subangular blocky structure; firm, slightly
sticky, plastic; few fine roots; common fine quartz grains; few soft
black concretions; very strongly acid; clear smooth boundary.
B3g-22 to 32 inches, light olive gray (5Y 6/2) sandy clay loam; common
medium prominent yellowish brown (10YR 5/8) mottles, and few
fine greenish gray (5BG 6/1) and light gray (2.5Y 7/2) mottles; mas-
sive; firm, slightly sticky, slightly plastic; common fine quartz
grains; few soft black concretions; strongly acid; gradual smooth
boundary.
C-32 to 43 inches, mixed yellowish brown (10YR 5/4 and 5/8), white
(2.5Y 8/2), and gray (5Y 5/1) sandy clay loam saprolite; massive; fri-
able, nonsticky, nonplastic; common fine quartz grains; common fine
dark minerals; horizon consists of 80 percent saprolite; strongly
acid.







SOIL SURVEY


The solum is 28 to 36 inches thick. Reaction throughout is very
strongly acid to strongly acid.
The A horizon has hue of 10YR or 2.5Y, value of 3 or 4, and chroma
of 2 or 3.
The B2 horizon has hue of 10YR to 5Y, value of 4 to 7, and chroma of
2 to 4. It has weak coarse angular blocky structure.
The C horizons are sandy clay loam and sandy loam.

Colinas series
The Colinas series consists of fine-loamy, carbonatic,
isohyperthermic Eutropeptic Rendolls. These soils are
moderately deep to soft limestone, are well drained, and
have a B horizon of brownish yellow clay loam. They
formed in moderately fine textured residuum of
limestone. The Colinas soils are on ridgetops and side
slopes. Slopes range from 12 to 60 percent, but are domi-
nantly 20 to 40 percent. The mean annual precipitation is
80 inches, and the mean annual temperature is 76 degrees
F.
The Colinas soils are associated with the Soller and
Tanama soils. They are underlain by softer limestone than
that of the Soller or Tanama soils. They are yellower than
the Tanama soils.
Typical pedon of Colinas clay loam, 40 to 60 percent
slopes, eroded, 500 feet southeast of junction of Highways
820 and 823, Bo. Quebrada Arenas, Toa Alta, P.R.

A1-0 to 11 inches, dark brown (10YR 3/3) clay loam; moderate medium
granular structure; friable, nonsticky, plastic; many fine roots; few
limestone fragments; mildly alkaline; clear smooth boundary.
B-11 to 26 inches, brownish yellow (10YR 6/6) clay loam; weak medium
subangular blocky structure; friable, nonsticky, slightly plastic; few
fine roots; few limestone fragments; mildly alkaline; clear smooth
boundary.
C1-26 to 48 inches, pale yellow (2.5Y 7/4) soft limestone crushing to
silty clay loam; massive; very friable, nonsticky, slightly plastic;
mildly alkaline.
C2-48 to 52 inches, mixture of yellow and white limestone containing
common fine and medium limestone fragments.
The solum is 15 to 30 inches thick. Reaction throughout is mildly al-
kaline.
The A horizon has hue of 10YR, value of 3 to 6, and chroma of 2 or
more.
The B2 horizon has hue of 10YR, value of 4 to 6, and chroma of 2 or
more.
The C horizon is clay loam or silty clay loam.

Coloso series
The Coloso series consists of fine, mixed, nonacid,
isohyperthermic Aeric Tropic Fluvaquents. These soils
are deep, are somewhat poorly drained, and have a C
horizon of dark grayish brown, dark brown, and dark
gray silty clay. They formed in fine textured and
moderately fine textured alluvial sediments of mixed
origin. The Coloso soils are on flood plains. Slopes range
from 0 to 2 percent. The mean annual precipitation is 80
inches, and the mean annual temperature is 78 degrees F.
The Coloso soils are associated with the Bajura, Toa,
and Dique soils. They are coarser textured and better
drained than the Bajura soils, but finer textured and
more poorly drained than the Toa and Dique soils.


Typical pedon of Coloso silty clay loam, 300 feet west
of road and 400 feet north of the terrace break, which is
approximately 2800 feet north of the Gurabo Experiment
Station's headquarters.
Ap-O to 7 inches, dark brown (10YR 3/3) silty clay loam; few fine
distinct dark reddish brown (2.5YR 3/4) mottles; medium coarse
granular structure; slightly hard, friable, nonsticky, slightly plastic;
many roots; medium acid; clear smooth boundary.
C1-7 to 16 inches, mixed dark brown (10YR 4/3) and dark yellowish
brown (10YR 4/4) silty clay loam; weak coarse subangular blocky
structure; friable, nonsticky, slightly plastic; many roots; organic
stains on ped surfaces; medium acid; clear smooth boundary.
C2g-16 to 32 inches, dark grayish brown (10YR 4/2) and light gray
(10YR 6/1) silty clay loam; many medium distinct dark yellowish
brown (10YR 4/4) mottles; weak coarse subangular blocky struc-
ture; firm, slightly sticky, plastic; black stains along fracture planes
and in root channels, the light gray color is more concentrated in
root channels and on fracture faces; many roots; medium acid;
gradual smooth boundary.
C3g-32 to 55 inches, greenish gray (5G 5/1) silty clay; many medium
distinct yellowish red (5YR 5/8) mottles; massive; firm, slightly
sticky, plastic; common roots; medium acid; gradual smooth bounda-
ry.
C4g-55 to 70 inches, greenish gray (5G 5/1) silty clay; many medium
distinct yellowish brown (10YR 5/6) mottles; massive; firm, slightly
sticky, plastic; few roots; medium acid.
The A horizon has hue of 10YR, value of 3 or 4, and chroma of 2 to 4.
The Cg horizon has hue of 10YR, 2.5Y, or 5G; value of 3 to 6; and
chroma of 2 or less.

Consume series
The Consumo series consists of clayey, mixed,
isohyperthermic Dystropeptic Tropudults. These soils are
deep, are well drained, and have a B2t horizon of yel-
lowish red clay. They formed in residuum of basic vol-
canic rocks. The Consumo soils are on side slopes and nar-
row ridges of strongly dissected, humid uplands. Slopes
range from 20 to 60 percent, but are dominantly 40 to 60
percent. The mean annual precipitation is 90 inches, and
the mean annual temperature is 76 degrees F.
The Consumo soils are associated with the Daguey, Hu-
matas, Morado, and Mucara soils. They are shallower to
saprolite than the Daguey and Humatas soils. They are
redder, are more acid, and have finer texture than the
Morado and Mucara soils.
Typical pedon of Consumo clay, 40 to 60 percent slopes,
0.7 mile south from kilometer 48.1 of Highway 1, along
farm road of La Mina de Oro Restaurant, then 20 feet
south.

Ap-0 to 10 inches, reddish brown (5YR 4/4) clay; moderate medium
granular structure; friable, slightly sticky, slightly plastic; many fine
roots; few small subrounded rock fragments; very strongly acid;
clear smooth boundary.
B2t-10 to 14 inches, yellowish red (5YR 5/6) clay; weak fine subangular
blocky structure; friable, slightly sticky, slightly plastic; many fine
roots; thin patchy clay films; few fine pores; few small subrounded
rock fragments; very strongly acid; clear smooth boundary.
B3-14 to 20 inches; yellowish red (5YR 5/6) clay; many medium distinct
red (2.5YR 4/6) and common fine distinct brownish yellow (10YR
6/6) mottles; weak fine subangular blocky structure; friable, slightly
sticky, slightly plastic; about 50 percent saprolite; very strongly
acid; clear smooth boundary.







SOIL SURVEY


The solum is 28 to 36 inches thick. Reaction throughout is very
strongly acid to strongly acid.
The A horizon has hue of 10YR or 2.5Y, value of 3 or 4, and chroma
of 2 or 3.
The B2 horizon has hue of 10YR to 5Y, value of 4 to 7, and chroma of
2 to 4. It has weak coarse angular blocky structure.
The C horizons are sandy clay loam and sandy loam.

Colinas series
The Colinas series consists of fine-loamy, carbonatic,
isohyperthermic Eutropeptic Rendolls. These soils are
moderately deep to soft limestone, are well drained, and
have a B horizon of brownish yellow clay loam. They
formed in moderately fine textured residuum of
limestone. The Colinas soils are on ridgetops and side
slopes. Slopes range from 12 to 60 percent, but are domi-
nantly 20 to 40 percent. The mean annual precipitation is
80 inches, and the mean annual temperature is 76 degrees
F.
The Colinas soils are associated with the Soller and
Tanama soils. They are underlain by softer limestone than
that of the Soller or Tanama soils. They are yellower than
the Tanama soils.
Typical pedon of Colinas clay loam, 40 to 60 percent
slopes, eroded, 500 feet southeast of junction of Highways
820 and 823, Bo. Quebrada Arenas, Toa Alta, P.R.

A1-0 to 11 inches, dark brown (10YR 3/3) clay loam; moderate medium
granular structure; friable, nonsticky, plastic; many fine roots; few
limestone fragments; mildly alkaline; clear smooth boundary.
B-11 to 26 inches, brownish yellow (10YR 6/6) clay loam; weak medium
subangular blocky structure; friable, nonsticky, slightly plastic; few
fine roots; few limestone fragments; mildly alkaline; clear smooth
boundary.
C1-26 to 48 inches, pale yellow (2.5Y 7/4) soft limestone crushing to
silty clay loam; massive; very friable, nonsticky, slightly plastic;
mildly alkaline.
C2-48 to 52 inches, mixture of yellow and white limestone containing
common fine and medium limestone fragments.
The solum is 15 to 30 inches thick. Reaction throughout is mildly al-
kaline.
The A horizon has hue of 10YR, value of 3 to 6, and chroma of 2 or
more.
The B2 horizon has hue of 10YR, value of 4 to 6, and chroma of 2 or
more.
The C horizon is clay loam or silty clay loam.

Coloso series
The Coloso series consists of fine, mixed, nonacid,
isohyperthermic Aeric Tropic Fluvaquents. These soils
are deep, are somewhat poorly drained, and have a C
horizon of dark grayish brown, dark brown, and dark
gray silty clay. They formed in fine textured and
moderately fine textured alluvial sediments of mixed
origin. The Coloso soils are on flood plains. Slopes range
from 0 to 2 percent. The mean annual precipitation is 80
inches, and the mean annual temperature is 78 degrees F.
The Coloso soils are associated with the Bajura, Toa,
and Dique soils. They are coarser textured and better
drained than the Bajura soils, but finer textured and
more poorly drained than the Toa and Dique soils.


Typical pedon of Coloso silty clay loam, 300 feet west
of road and 400 feet north of the terrace break, which is
approximately 2800 feet north of the Gurabo Experiment
Station's headquarters.
Ap-O to 7 inches, dark brown (10YR 3/3) silty clay loam; few fine
distinct dark reddish brown (2.5YR 3/4) mottles; medium coarse
granular structure; slightly hard, friable, nonsticky, slightly plastic;
many roots; medium acid; clear smooth boundary.
C1-7 to 16 inches, mixed dark brown (10YR 4/3) and dark yellowish
brown (10YR 4/4) silty clay loam; weak coarse subangular blocky
structure; friable, nonsticky, slightly plastic; many roots; organic
stains on ped surfaces; medium acid; clear smooth boundary.
C2g-16 to 32 inches, dark grayish brown (10YR 4/2) and light gray
(10YR 6/1) silty clay loam; many medium distinct dark yellowish
brown (10YR 4/4) mottles; weak coarse subangular blocky struc-
ture; firm, slightly sticky, plastic; black stains along fracture planes
and in root channels, the light gray color is more concentrated in
root channels and on fracture faces; many roots; medium acid;
gradual smooth boundary.
C3g-32 to 55 inches, greenish gray (5G 5/1) silty clay; many medium
distinct yellowish red (5YR 5/8) mottles; massive; firm, slightly
sticky, plastic; common roots; medium acid; gradual smooth bounda-
ry.
C4g-55 to 70 inches, greenish gray (5G 5/1) silty clay; many medium
distinct yellowish brown (10YR 5/6) mottles; massive; firm, slightly
sticky, plastic; few roots; medium acid.
The A horizon has hue of 10YR, value of 3 or 4, and chroma of 2 to 4.
The Cg horizon has hue of 10YR, 2.5Y, or 5G; value of 3 to 6; and
chroma of 2 or less.

Consume series
The Consumo series consists of clayey, mixed,
isohyperthermic Dystropeptic Tropudults. These soils are
deep, are well drained, and have a B2t horizon of yel-
lowish red clay. They formed in residuum of basic vol-
canic rocks. The Consumo soils are on side slopes and nar-
row ridges of strongly dissected, humid uplands. Slopes
range from 20 to 60 percent, but are dominantly 40 to 60
percent. The mean annual precipitation is 90 inches, and
the mean annual temperature is 76 degrees F.
The Consumo soils are associated with the Daguey, Hu-
matas, Morado, and Mucara soils. They are shallower to
saprolite than the Daguey and Humatas soils. They are
redder, are more acid, and have finer texture than the
Morado and Mucara soils.
Typical pedon of Consumo clay, 40 to 60 percent slopes,
0.7 mile south from kilometer 48.1 of Highway 1, along
farm road of La Mina de Oro Restaurant, then 20 feet
south.

Ap-0 to 10 inches, reddish brown (5YR 4/4) clay; moderate medium
granular structure; friable, slightly sticky, slightly plastic; many fine
roots; few small subrounded rock fragments; very strongly acid;
clear smooth boundary.
B2t-10 to 14 inches, yellowish red (5YR 5/6) clay; weak fine subangular
blocky structure; friable, slightly sticky, slightly plastic; many fine
roots; thin patchy clay films; few fine pores; few small subrounded
rock fragments; very strongly acid; clear smooth boundary.
B3-14 to 20 inches; yellowish red (5YR 5/6) clay; many medium distinct
red (2.5YR 4/6) and common fine distinct brownish yellow (10YR
6/6) mottles; weak fine subangular blocky structure; friable, slightly
sticky, slightly plastic; about 50 percent saprolite; very strongly
acid; clear smooth boundary.







SOIL SURVEY


The solum is 28 to 36 inches thick. Reaction throughout is very
strongly acid to strongly acid.
The A horizon has hue of 10YR or 2.5Y, value of 3 or 4, and chroma
of 2 or 3.
The B2 horizon has hue of 10YR to 5Y, value of 4 to 7, and chroma of
2 to 4. It has weak coarse angular blocky structure.
The C horizons are sandy clay loam and sandy loam.

Colinas series
The Colinas series consists of fine-loamy, carbonatic,
isohyperthermic Eutropeptic Rendolls. These soils are
moderately deep to soft limestone, are well drained, and
have a B horizon of brownish yellow clay loam. They
formed in moderately fine textured residuum of
limestone. The Colinas soils are on ridgetops and side
slopes. Slopes range from 12 to 60 percent, but are domi-
nantly 20 to 40 percent. The mean annual precipitation is
80 inches, and the mean annual temperature is 76 degrees
F.
The Colinas soils are associated with the Soller and
Tanama soils. They are underlain by softer limestone than
that of the Soller or Tanama soils. They are yellower than
the Tanama soils.
Typical pedon of Colinas clay loam, 40 to 60 percent
slopes, eroded, 500 feet southeast of junction of Highways
820 and 823, Bo. Quebrada Arenas, Toa Alta, P.R.

A1-0 to 11 inches, dark brown (10YR 3/3) clay loam; moderate medium
granular structure; friable, nonsticky, plastic; many fine roots; few
limestone fragments; mildly alkaline; clear smooth boundary.
B-11 to 26 inches, brownish yellow (10YR 6/6) clay loam; weak medium
subangular blocky structure; friable, nonsticky, slightly plastic; few
fine roots; few limestone fragments; mildly alkaline; clear smooth
boundary.
C1-26 to 48 inches, pale yellow (2.5Y 7/4) soft limestone crushing to
silty clay loam; massive; very friable, nonsticky, slightly plastic;
mildly alkaline.
C2-48 to 52 inches, mixture of yellow and white limestone containing
common fine and medium limestone fragments.
The solum is 15 to 30 inches thick. Reaction throughout is mildly al-
kaline.
The A horizon has hue of 10YR, value of 3 to 6, and chroma of 2 or
more.
The B2 horizon has hue of 10YR, value of 4 to 6, and chroma of 2 or
more.
The C horizon is clay loam or silty clay loam.

Coloso series
The Coloso series consists of fine, mixed, nonacid,
isohyperthermic Aeric Tropic Fluvaquents. These soils
are deep, are somewhat poorly drained, and have a C
horizon of dark grayish brown, dark brown, and dark
gray silty clay. They formed in fine textured and
moderately fine textured alluvial sediments of mixed
origin. The Coloso soils are on flood plains. Slopes range
from 0 to 2 percent. The mean annual precipitation is 80
inches, and the mean annual temperature is 78 degrees F.
The Coloso soils are associated with the Bajura, Toa,
and Dique soils. They are coarser textured and better
drained than the Bajura soils, but finer textured and
more poorly drained than the Toa and Dique soils.


Typical pedon of Coloso silty clay loam, 300 feet west
of road and 400 feet north of the terrace break, which is
approximately 2800 feet north of the Gurabo Experiment
Station's headquarters.
Ap-O to 7 inches, dark brown (10YR 3/3) silty clay loam; few fine
distinct dark reddish brown (2.5YR 3/4) mottles; medium coarse
granular structure; slightly hard, friable, nonsticky, slightly plastic;
many roots; medium acid; clear smooth boundary.
C1-7 to 16 inches, mixed dark brown (10YR 4/3) and dark yellowish
brown (10YR 4/4) silty clay loam; weak coarse subangular blocky
structure; friable, nonsticky, slightly plastic; many roots; organic
stains on ped surfaces; medium acid; clear smooth boundary.
C2g-16 to 32 inches, dark grayish brown (10YR 4/2) and light gray
(10YR 6/1) silty clay loam; many medium distinct dark yellowish
brown (10YR 4/4) mottles; weak coarse subangular blocky struc-
ture; firm, slightly sticky, plastic; black stains along fracture planes
and in root channels, the light gray color is more concentrated in
root channels and on fracture faces; many roots; medium acid;
gradual smooth boundary.
C3g-32 to 55 inches, greenish gray (5G 5/1) silty clay; many medium
distinct yellowish red (5YR 5/8) mottles; massive; firm, slightly
sticky, plastic; common roots; medium acid; gradual smooth bounda-
ry.
C4g-55 to 70 inches, greenish gray (5G 5/1) silty clay; many medium
distinct yellowish brown (10YR 5/6) mottles; massive; firm, slightly
sticky, plastic; few roots; medium acid.
The A horizon has hue of 10YR, value of 3 or 4, and chroma of 2 to 4.
The Cg horizon has hue of 10YR, 2.5Y, or 5G; value of 3 to 6; and
chroma of 2 or less.

Consume series
The Consumo series consists of clayey, mixed,
isohyperthermic Dystropeptic Tropudults. These soils are
deep, are well drained, and have a B2t horizon of yel-
lowish red clay. They formed in residuum of basic vol-
canic rocks. The Consumo soils are on side slopes and nar-
row ridges of strongly dissected, humid uplands. Slopes
range from 20 to 60 percent, but are dominantly 40 to 60
percent. The mean annual precipitation is 90 inches, and
the mean annual temperature is 76 degrees F.
The Consumo soils are associated with the Daguey, Hu-
matas, Morado, and Mucara soils. They are shallower to
saprolite than the Daguey and Humatas soils. They are
redder, are more acid, and have finer texture than the
Morado and Mucara soils.
Typical pedon of Consumo clay, 40 to 60 percent slopes,
0.7 mile south from kilometer 48.1 of Highway 1, along
farm road of La Mina de Oro Restaurant, then 20 feet
south.

Ap-0 to 10 inches, reddish brown (5YR 4/4) clay; moderate medium
granular structure; friable, slightly sticky, slightly plastic; many fine
roots; few small subrounded rock fragments; very strongly acid;
clear smooth boundary.
B2t-10 to 14 inches, yellowish red (5YR 5/6) clay; weak fine subangular
blocky structure; friable, slightly sticky, slightly plastic; many fine
roots; thin patchy clay films; few fine pores; few small subrounded
rock fragments; very strongly acid; clear smooth boundary.
B3-14 to 20 inches; yellowish red (5YR 5/6) clay; many medium distinct
red (2.5YR 4/6) and common fine distinct brownish yellow (10YR
6/6) mottles; weak fine subangular blocky structure; friable, slightly
sticky, slightly plastic; about 50 percent saprolite; very strongly
acid; clear smooth boundary.







SAN JUAN AREA, PUERTO RICO


C-20 to 46 inches, variegated red (2.5YR 4/6 and 5/6), brownish yellow
(10YR 6/6), and yellowish red (5YR 5/6), silty clay loam saprolite;
massive; very friable, slightly sticky, slightly plastic; original rock
structure visible; can be crushed with fingers; very strongly acid.
The solum is 14 to 24 inches thick. Reaction throughout is very
strongly acid.
The A horizon has hue of 5YR or 2.5YR, value of 3 to 5, and chroma
of 4 to 6.
The B2 horizon has hue of 5YR or 2.5YR, value of 4 or 5, and chroma
of 6 or more.

Corozal series

The Corozal series consists of clayey, mixed,
isohyperthermic Aquic Tropudults. These soils are deep,
are somewhat poorly drained, and have a B2 horizon of
red clay. They formed in residuum of volcanic rocks. The
sloping Corozal soils are on interfluves of strongly dis-
sected low volcanic hills. Slopes range from 5 to 12 per-
cent. The mean annual precipitation is 80 inches, and the
mean annual temperature is 75 degrees F.
The Corozal soils are associated with the Consumo and
Humatas soils. They have a thicker solum and are more
poorly drained than the Consumo and Humatas soils.
Typical pedon of Corozal clay, 5 to 12 percent slopes, 3
miles southwest of the town of Corozal on the Corozal
Experiment Station farm, 60 feet east of cattle weighing
pen.

Ap-0 to 7 inches, dark reddish brown (5YR 3/4) clay; moderate fine su-
bangular blocky structure; firm, slightly sticky, slightly plastic;
many fine roots; very strongly acid; clear wavy boundary.
B1-7 to 9 inches, mixed dark red (2.5YR 3/6) and grayish brown (10YR
5/2) clay; moderate fine subangular blocky structure; firm, slightly
sticky, plastic; thick continuous clay films; many fine roots; very
strongly acid; clear wavy boundary.
B21t-9 to 13 inches, red (2.5YR 4/6) clay; reddish brown (5YR 4/4) on
ped surfaces and root channels; moderate medium prismatic struc-
ture parting to moderate medium subangular blocky; firm, slightly
sticky, plastic; thick continuous clay films; many fine roots; very
strongly acid; gradual wavy boundary.
B22t-13 to 24 inches, red (2.5YR 4/6) clay; yellowish brown (10YR 5/6)
coatings on ped surfaces and in root channels; moderate medium su-
bangular blocky structure; firm, slightly sticky, plastic; thin continu-
ous clay films on ped faces and in root channels; common fine roots;
very strongly acid; gradual wavy boundary.
B23t-24 to 32 inches, red (2.5YR 5/6) clay; yellowish brown (10YR 5/6)
coatings on ped surfaces and in root channels; moderate medium su-
bangular blocky structure parting to weak fine subangular blocky;
friable, slightly sticky, slightly plastic; very few patchy clay films on
vertical ped faces; few fine roots; very strongly acid; gradual wavy
boundary.
B3-32 to 40 inches, yellowish red (5YR 5/6) clay; weak fine subangular
blocky structure; friable, slightly sticky, slightly plastic; very few
patchy clay films on vertical ped faces; about 30 percent by volume
is saprolite; pseudomorphs of feldspars easily crushed to shiny faces
(kaolin books); very strongly acid; gradual irregular boundary.
C-40 to 60 inches; variegated yellowish red (5YR 5/6), light gray (5YR
7/1), and strong brown (7.5YR 5/6) clay loam saprolite; massive; fri-
able, slightly sticky, slightly plastic; saprolite is easily crushed with
fingers; rock structure visible; pseudomorphs of feldspars easily
crushed to shiny faces (kaolin books); very strongly acid.
The solum is 40 to 50 inches thick. Reaction is very strongly acid.
The A horizon has hue of 5YR or 7.5YR, value of 3 or 4, and chroma


The B2 horizon has hue of 2.5YR or 5YR, value of 4 or 5, and chroma
of 6 to 8. It has strong to moderate subangular blocky structure or
prismatic structure parting to subangular blocky.

Daguey series
The Daguey series consists of clayey, oxidic,
isohyperthermic Orthoxic Tropohumults. These soils are
deep, are well drained, and have a B horizon of reddish
clay. They formed in the residuum of basic volcanic rocks.
The Daguey soils are on the more stable side slopes,
ridgetops, and foot slopes of the humid volcanic uplands.
Slopes range from 2 to 20 percent, but are dominantly 12
to 20 percent. The mean annual precipitation is 75 inches,
and the mean annual temperature is 78 degrees F.
The Daguey soils are associated with the Humatas and
Consumo soils. The Daguey soils are more leached and
have a thicker solum than the Humatas and Consumo
soils.
Typical pedon of Daguey clay, 12 to 20 percent slopes,
40 feet west of Highway 813, then 80 feet south of road
junction to house, Cibuco SCD, P.R.

Ap-0 to 10 inches, dark brown (7.5YR 4/4) clay; weak medium suban-
gular blocky structure parting to moderate fine granular; firm,
slightly sticky, slightly plastic; very strongly acid; abrupt wavy
boundary.
BI-10 to 14 inches, reddish brown (5YR 5/4) clay; weak medium suban-
gular blocky structure; firm, slightly sticky, slightly plastic; thin
patchy clay films; very strongly acid; clear smooth boundary.
B21t-14 to 23 inches, yellowish red (5YR 4/6) clay; few medium distinct
yellowish brown (10YR 5/4) mottles; weak coarse prismatic struc-
ture parting to moderate medium subangular and angular blocky;
firm, slightly sticky, slightly plastic; thin patchy clay films; very
strongly acid; clear smooth boundary.
B22t-23 to 31 inches, red (2.5YR 4/6) clay; strong medium and fine sub-
angular blocky structure; firm, slightly sticky, slightly plastic; thin
continuous clay films on ped faces; very strongly acid; gradual
smooth boundary.
B23t-31 to 43 inches, red (2.5YR 4/6) clay; strong medium and fine sub-
angular blocky structure; firm, slightly sticky, slightly plastic; thin
patchy clay films; very strongly acid; gradual smooth boundary.
B24t-43 to 59 inches, red (2.5YR 4/6) clay; moderate fine subangular
blocky structure; firm, slightly sticky, slightly plastic; thin patchy
clay films; very strongly acid; gradual smooth boundary.
B3-59 to 72 inches, red (2.5YR 4/6) clay; weak medium and fine suban-
gular blocky structure; firm, slightly sticky, slightly plastic; very
thin patchy clay films; few small angular fragments of rock; very
strongly acid; clear smooth boundary.
C1-72 to 86 inches, yellowish red (5YR 4/6) silty clay loam; common
fine distinct strong brown (7.5YR 5/6) and reddish yellow (7.5YR
6/6) mottles; massive but with some evidence of original rock struc-
ture; friable, slightly sticky, slightly plastic; very strongly acid;
gradual smooth boundary.
C2-86 to 90 inches, yellowish red (5YR 4/6) silty clay loam saprolite
with well defined rock structure; common fine distinct strong brown
(7.5YR 5/6) and reddish yellow (7.5YR 6/6) mottles; very strongly
acid.

The solum is 50 to 80 inches thick. Reaction throughout is very
strongly acid.
The A horizon has hue of 7.5YR or 5YR, value of 3 to 5, and chroma
of 2 to 4.
The B2 horizon has hue of 10R or 2.5YR, value of 4 or 5, and chroma
of 6 to 8. It has moderate to strong medium and fine subangular blocky
structure.







SAN JUAN AREA, PUERTO RICO


C-20 to 46 inches, variegated red (2.5YR 4/6 and 5/6), brownish yellow
(10YR 6/6), and yellowish red (5YR 5/6), silty clay loam saprolite;
massive; very friable, slightly sticky, slightly plastic; original rock
structure visible; can be crushed with fingers; very strongly acid.
The solum is 14 to 24 inches thick. Reaction throughout is very
strongly acid.
The A horizon has hue of 5YR or 2.5YR, value of 3 to 5, and chroma
of 4 to 6.
The B2 horizon has hue of 5YR or 2.5YR, value of 4 or 5, and chroma
of 6 or more.

Corozal series

The Corozal series consists of clayey, mixed,
isohyperthermic Aquic Tropudults. These soils are deep,
are somewhat poorly drained, and have a B2 horizon of
red clay. They formed in residuum of volcanic rocks. The
sloping Corozal soils are on interfluves of strongly dis-
sected low volcanic hills. Slopes range from 5 to 12 per-
cent. The mean annual precipitation is 80 inches, and the
mean annual temperature is 75 degrees F.
The Corozal soils are associated with the Consumo and
Humatas soils. They have a thicker solum and are more
poorly drained than the Consumo and Humatas soils.
Typical pedon of Corozal clay, 5 to 12 percent slopes, 3
miles southwest of the town of Corozal on the Corozal
Experiment Station farm, 60 feet east of cattle weighing
pen.

Ap-0 to 7 inches, dark reddish brown (5YR 3/4) clay; moderate fine su-
bangular blocky structure; firm, slightly sticky, slightly plastic;
many fine roots; very strongly acid; clear wavy boundary.
B1-7 to 9 inches, mixed dark red (2.5YR 3/6) and grayish brown (10YR
5/2) clay; moderate fine subangular blocky structure; firm, slightly
sticky, plastic; thick continuous clay films; many fine roots; very
strongly acid; clear wavy boundary.
B21t-9 to 13 inches, red (2.5YR 4/6) clay; reddish brown (5YR 4/4) on
ped surfaces and root channels; moderate medium prismatic struc-
ture parting to moderate medium subangular blocky; firm, slightly
sticky, plastic; thick continuous clay films; many fine roots; very
strongly acid; gradual wavy boundary.
B22t-13 to 24 inches, red (2.5YR 4/6) clay; yellowish brown (10YR 5/6)
coatings on ped surfaces and in root channels; moderate medium su-
bangular blocky structure; firm, slightly sticky, plastic; thin continu-
ous clay films on ped faces and in root channels; common fine roots;
very strongly acid; gradual wavy boundary.
B23t-24 to 32 inches, red (2.5YR 5/6) clay; yellowish brown (10YR 5/6)
coatings on ped surfaces and in root channels; moderate medium su-
bangular blocky structure parting to weak fine subangular blocky;
friable, slightly sticky, slightly plastic; very few patchy clay films on
vertical ped faces; few fine roots; very strongly acid; gradual wavy
boundary.
B3-32 to 40 inches, yellowish red (5YR 5/6) clay; weak fine subangular
blocky structure; friable, slightly sticky, slightly plastic; very few
patchy clay films on vertical ped faces; about 30 percent by volume
is saprolite; pseudomorphs of feldspars easily crushed to shiny faces
(kaolin books); very strongly acid; gradual irregular boundary.
C-40 to 60 inches; variegated yellowish red (5YR 5/6), light gray (5YR
7/1), and strong brown (7.5YR 5/6) clay loam saprolite; massive; fri-
able, slightly sticky, slightly plastic; saprolite is easily crushed with
fingers; rock structure visible; pseudomorphs of feldspars easily
crushed to shiny faces (kaolin books); very strongly acid.
The solum is 40 to 50 inches thick. Reaction is very strongly acid.
The A horizon has hue of 5YR or 7.5YR, value of 3 or 4, and chroma


The B2 horizon has hue of 2.5YR or 5YR, value of 4 or 5, and chroma
of 6 to 8. It has strong to moderate subangular blocky structure or
prismatic structure parting to subangular blocky.

Daguey series
The Daguey series consists of clayey, oxidic,
isohyperthermic Orthoxic Tropohumults. These soils are
deep, are well drained, and have a B horizon of reddish
clay. They formed in the residuum of basic volcanic rocks.
The Daguey soils are on the more stable side slopes,
ridgetops, and foot slopes of the humid volcanic uplands.
Slopes range from 2 to 20 percent, but are dominantly 12
to 20 percent. The mean annual precipitation is 75 inches,
and the mean annual temperature is 78 degrees F.
The Daguey soils are associated with the Humatas and
Consumo soils. The Daguey soils are more leached and
have a thicker solum than the Humatas and Consumo
soils.
Typical pedon of Daguey clay, 12 to 20 percent slopes,
40 feet west of Highway 813, then 80 feet south of road
junction to house, Cibuco SCD, P.R.

Ap-0 to 10 inches, dark brown (7.5YR 4/4) clay; weak medium suban-
gular blocky structure parting to moderate fine granular; firm,
slightly sticky, slightly plastic; very strongly acid; abrupt wavy
boundary.
BI-10 to 14 inches, reddish brown (5YR 5/4) clay; weak medium suban-
gular blocky structure; firm, slightly sticky, slightly plastic; thin
patchy clay films; very strongly acid; clear smooth boundary.
B21t-14 to 23 inches, yellowish red (5YR 4/6) clay; few medium distinct
yellowish brown (10YR 5/4) mottles; weak coarse prismatic struc-
ture parting to moderate medium subangular and angular blocky;
firm, slightly sticky, slightly plastic; thin patchy clay films; very
strongly acid; clear smooth boundary.
B22t-23 to 31 inches, red (2.5YR 4/6) clay; strong medium and fine sub-
angular blocky structure; firm, slightly sticky, slightly plastic; thin
continuous clay films on ped faces; very strongly acid; gradual
smooth boundary.
B23t-31 to 43 inches, red (2.5YR 4/6) clay; strong medium and fine sub-
angular blocky structure; firm, slightly sticky, slightly plastic; thin
patchy clay films; very strongly acid; gradual smooth boundary.
B24t-43 to 59 inches, red (2.5YR 4/6) clay; moderate fine subangular
blocky structure; firm, slightly sticky, slightly plastic; thin patchy
clay films; very strongly acid; gradual smooth boundary.
B3-59 to 72 inches, red (2.5YR 4/6) clay; weak medium and fine suban-
gular blocky structure; firm, slightly sticky, slightly plastic; very
thin patchy clay films; few small angular fragments of rock; very
strongly acid; clear smooth boundary.
C1-72 to 86 inches, yellowish red (5YR 4/6) silty clay loam; common
fine distinct strong brown (7.5YR 5/6) and reddish yellow (7.5YR
6/6) mottles; massive but with some evidence of original rock struc-
ture; friable, slightly sticky, slightly plastic; very strongly acid;
gradual smooth boundary.
C2-86 to 90 inches, yellowish red (5YR 4/6) silty clay loam saprolite
with well defined rock structure; common fine distinct strong brown
(7.5YR 5/6) and reddish yellow (7.5YR 6/6) mottles; very strongly
acid.

The solum is 50 to 80 inches thick. Reaction throughout is very
strongly acid.
The A horizon has hue of 7.5YR or 5YR, value of 3 to 5, and chroma
of 2 to 4.
The B2 horizon has hue of 10R or 2.5YR, value of 4 or 5, and chroma
of 6 to 8. It has moderate to strong medium and fine subangular blocky
structure.






SOIL SURVEY


Descalabrado series
The Descalabrado series consists of clayey, mixed,
isohyperthermic Lithic Vertic Ustropepts. These soils are
shallow, are well drained, and have a B horizon of dark
brown gravelly clay. They formed in residuum of basic
volcanic rocks. The Descalabrado soils are on foot slopes,
long and short side slopes, and ridgetops of semiarid vol-
canic uplands. Slopes range from 40 to 60 percent. The
mean annual precipitation is 40 inches, and the mean an-
nual temperature is 80 degrees F.
The Descalabrado soils are associated with the
Guayama soils. The Descalabrado soils have colors with
yellower hues and lack the argillic horizons of the
Guayama soils.
Typical pedon of Descalabrado clay loam, 40 to 60 per-
cent slopes, 1250 feet south from elementary school of Bo.
Cercadillo, Cayey, P.R.
A1-0 to 5 inches, very dark grayish brown (10YR 3/2) clay loam;
moderate fine granular structure; friable, nonsticky, slightly plastic,
few fine roots; few fine pores; few rock fragments 2 millimeters to
25 millimeters in diameter; neutral; clear smooth boundary.
B-5 to 11 inches, dark brown (10YR 3/3) gravelly clay; weak fine sub-
angular blocky structure; firm, slightly sticky, slightly plastic; few
fine roots; few fine pores; 20 percent rock fragments 2 millimeters
to 25 millimeters in diameter; neutral; clear smooth boundary.
C-11 to 17 inches, mixed dark yellowish brown (10YR 3/4 and 10YR
4/4) and olive (5Y 5/3) gravelly sandy clay loam weathered rock;
massive; friable, nonsticky, slightly plastic; 25 percent rock frag-
ments 1 to 3 inches in diameter; neutral; clear abrupt boundary.
R-17 inches, hard semiconsolidated volcanic rock.
The solum is 8 to 14 inches thick. Reaction throughout is neutral.
The A horizon has hue of 10YR and 7.5YR, value of 2 or 3, and
chroma of 2 or 3.
The B horizon has hue of 10YR or 7.5YR, value of 3 or 4, and chroma
of 2 to 4.

Dique series
The Dique series consists of fine-loamy, mixed,
isohyperthermic Fluventic Eutropepts. These soils are
deep, are well drained, and have a B2 horizon of dark yel-
lowish brown loam. They formed in medium textured allu-
vial sediments of mixed origin. The Dique soils are on
river flood plains. Slopes range from 0 to 2 percent. The
mean annual precipitation is 72 inches, and the mean an-
nual temperature is 77 degrees F.
The Dique soils are associated with the Toa, Bajura,
Coloso, and Reilly soils. They are better drained and have
coarser textures than the Bajura and Coloso soils. They
are thicker and lack the gravelly layers of the Reilly soils.
They are coarser textured and better drained than the
Toa soils.
Typical pedon of Dique loam, 100 feet west from en-
trance of Gurabo Experiment Station, then 75 feet north
of Highway 941.
Ap-0 to 6 inches, dark brown (10YR 4/3) loam; weak fine granular
structure; friable, nonsticky, slightly plastic; many fine roots; medi-
um acid; clear smooth boundary.
Bl-6 to 16 inches, dark brown (10YR 4/3) loam; weak medium suban-
gular blocky structure; friable, nonsticky, slightly plastic; common
fine roots; few fine black concretions; medium acid; abrupt wavy
boundary.


B2-16 to 20 inches, dark yellowish brown (10YR 4/4) loam; weak fine
subangular blocky structure; friable, slightly sticky, slightly plastic;
common fine roots; medium acid; gradual smooth boundary.
B3-20 to 36 inches, dark brown (10YR 4/3) loam; weak fine subangular
blocky structure; friable; medium acid; abrupt smooth boundary.
C-36 to 54 inches, dark yellowish brown (10YR 4/4) loam; friable, non-
sticky, nonplastic; medium acid.
The solum is 20 to 40 inches thick. Reaction throughout is medium
acid.
The A and B horizons have hue of 10YR, value of 4 or 5, and chroma
of 2 to 4.

Durados series
The Durados series consists of sandy, mixed,
isohyperthermic Fluventic Hapludolls. These soils are
deep, are excessively drained, and have dark grayish
brown sandy loam Ap horizons over dark grayish brown
loamy sand and sand C horizons. They formed in coarse
textured materials which consist of sand size shell frag-
ments and miscellaneous volcanic subrounded fragments.
The Durados soils are on the coast at elevations close to
sea level. Slope ranges from 0 to 2 percent. The mean an-
nual precipitation is 70 inches, and the mean annual tem-
perature is 80 degrees F.
The Durados soils are associated with the Coloso, Toa,
and Catano soils. They are coarser textured and more
permeable than the Coloso and Toa soils. They are finer
textured than the Catano soils.
Typical pedon of Durados sandy loam, 0.2 mile
northwest of kilometer 19.9, Highway 165, following a
farm road, then 150 feet north.
Ap-0 to 14 inches, very dark grayish brown (10YR 3/2) sandy loam;
massive; very friable, nonsticky, nonplastic; few fine roots; few
medium coconut roots; few quartz grains; neutral; abrupt smooth
boundary.
C1-14 to 23 inches, very dark grayish brown (10YR 3/2) loamy sand;
single grain; loose; few fine cemented sandy concretions; neutral;
abrupt smooth boundary.
C2-23 to 38 inches, very pale brown (10YR 7/3) and very dark grayish
brown (10YR 3/2) sand; single grain; loose; about 25 percent of
horizon is light gray (5Y 7/1) cemented sand that is strongly cal-
careous; moderately alkaline; abrupt smooth boundary.
C3-38 to 60 inches; sand that is mixed dark yellowish brown (10YR
4/4), black (10YR 2/1), brownish yellow (10YR 6/6), and yellowish
brown (10YR 6/4); single grain; loose; this horizon has a thick layer
of cemented sand that could be penetrated with an auger; few sea
shells; common quartz grains; strongly alkaline, calcareous.
The mollic epipedon is 10 to 30 inches thick. Reaction throughout is
neutral to strongly alkaline.
The A horizon has hue of 10YR or 7.5YR, value and chroma of 2 or 3.

Estacion series
The Estacion series consists of fine loamy over sandy
or sandy-skeletal, mixed, isohyperthermic Fluventic
Hapludolls. These soils are shallow, are well drained, and
have an Ap horizon of dark brown silty clay loam and a C
horizon of very dark grayish brown gravelly clay loam
and sand. They formed in stratified moderately fine tex-
tured sediments over gravelly layers of mixed origin. The
Estacion soils are on river flood plains. Slopes range from
0 to 2 percent. The mean annual precipitation is 70 inches,
and the mean annual temperature is 80 degrees F.






SOIL SURVEY


Descalabrado series
The Descalabrado series consists of clayey, mixed,
isohyperthermic Lithic Vertic Ustropepts. These soils are
shallow, are well drained, and have a B horizon of dark
brown gravelly clay. They formed in residuum of basic
volcanic rocks. The Descalabrado soils are on foot slopes,
long and short side slopes, and ridgetops of semiarid vol-
canic uplands. Slopes range from 40 to 60 percent. The
mean annual precipitation is 40 inches, and the mean an-
nual temperature is 80 degrees F.
The Descalabrado soils are associated with the
Guayama soils. The Descalabrado soils have colors with
yellower hues and lack the argillic horizons of the
Guayama soils.
Typical pedon of Descalabrado clay loam, 40 to 60 per-
cent slopes, 1250 feet south from elementary school of Bo.
Cercadillo, Cayey, P.R.
A1-0 to 5 inches, very dark grayish brown (10YR 3/2) clay loam;
moderate fine granular structure; friable, nonsticky, slightly plastic,
few fine roots; few fine pores; few rock fragments 2 millimeters to
25 millimeters in diameter; neutral; clear smooth boundary.
B-5 to 11 inches, dark brown (10YR 3/3) gravelly clay; weak fine sub-
angular blocky structure; firm, slightly sticky, slightly plastic; few
fine roots; few fine pores; 20 percent rock fragments 2 millimeters
to 25 millimeters in diameter; neutral; clear smooth boundary.
C-11 to 17 inches, mixed dark yellowish brown (10YR 3/4 and 10YR
4/4) and olive (5Y 5/3) gravelly sandy clay loam weathered rock;
massive; friable, nonsticky, slightly plastic; 25 percent rock frag-
ments 1 to 3 inches in diameter; neutral; clear abrupt boundary.
R-17 inches, hard semiconsolidated volcanic rock.
The solum is 8 to 14 inches thick. Reaction throughout is neutral.
The A horizon has hue of 10YR and 7.5YR, value of 2 or 3, and
chroma of 2 or 3.
The B horizon has hue of 10YR or 7.5YR, value of 3 or 4, and chroma
of 2 to 4.

Dique series
The Dique series consists of fine-loamy, mixed,
isohyperthermic Fluventic Eutropepts. These soils are
deep, are well drained, and have a B2 horizon of dark yel-
lowish brown loam. They formed in medium textured allu-
vial sediments of mixed origin. The Dique soils are on
river flood plains. Slopes range from 0 to 2 percent. The
mean annual precipitation is 72 inches, and the mean an-
nual temperature is 77 degrees F.
The Dique soils are associated with the Toa, Bajura,
Coloso, and Reilly soils. They are better drained and have
coarser textures than the Bajura and Coloso soils. They
are thicker and lack the gravelly layers of the Reilly soils.
They are coarser textured and better drained than the
Toa soils.
Typical pedon of Dique loam, 100 feet west from en-
trance of Gurabo Experiment Station, then 75 feet north
of Highway 941.
Ap-0 to 6 inches, dark brown (10YR 4/3) loam; weak fine granular
structure; friable, nonsticky, slightly plastic; many fine roots; medi-
um acid; clear smooth boundary.
Bl-6 to 16 inches, dark brown (10YR 4/3) loam; weak medium suban-
gular blocky structure; friable, nonsticky, slightly plastic; common
fine roots; few fine black concretions; medium acid; abrupt wavy
boundary.


B2-16 to 20 inches, dark yellowish brown (10YR 4/4) loam; weak fine
subangular blocky structure; friable, slightly sticky, slightly plastic;
common fine roots; medium acid; gradual smooth boundary.
B3-20 to 36 inches, dark brown (10YR 4/3) loam; weak fine subangular
blocky structure; friable; medium acid; abrupt smooth boundary.
C-36 to 54 inches, dark yellowish brown (10YR 4/4) loam; friable, non-
sticky, nonplastic; medium acid.
The solum is 20 to 40 inches thick. Reaction throughout is medium
acid.
The A and B horizons have hue of 10YR, value of 4 or 5, and chroma
of 2 to 4.

Durados series
The Durados series consists of sandy, mixed,
isohyperthermic Fluventic Hapludolls. These soils are
deep, are excessively drained, and have dark grayish
brown sandy loam Ap horizons over dark grayish brown
loamy sand and sand C horizons. They formed in coarse
textured materials which consist of sand size shell frag-
ments and miscellaneous volcanic subrounded fragments.
The Durados soils are on the coast at elevations close to
sea level. Slope ranges from 0 to 2 percent. The mean an-
nual precipitation is 70 inches, and the mean annual tem-
perature is 80 degrees F.
The Durados soils are associated with the Coloso, Toa,
and Catano soils. They are coarser textured and more
permeable than the Coloso and Toa soils. They are finer
textured than the Catano soils.
Typical pedon of Durados sandy loam, 0.2 mile
northwest of kilometer 19.9, Highway 165, following a
farm road, then 150 feet north.
Ap-0 to 14 inches, very dark grayish brown (10YR 3/2) sandy loam;
massive; very friable, nonsticky, nonplastic; few fine roots; few
medium coconut roots; few quartz grains; neutral; abrupt smooth
boundary.
C1-14 to 23 inches, very dark grayish brown (10YR 3/2) loamy sand;
single grain; loose; few fine cemented sandy concretions; neutral;
abrupt smooth boundary.
C2-23 to 38 inches, very pale brown (10YR 7/3) and very dark grayish
brown (10YR 3/2) sand; single grain; loose; about 25 percent of
horizon is light gray (5Y 7/1) cemented sand that is strongly cal-
careous; moderately alkaline; abrupt smooth boundary.
C3-38 to 60 inches; sand that is mixed dark yellowish brown (10YR
4/4), black (10YR 2/1), brownish yellow (10YR 6/6), and yellowish
brown (10YR 6/4); single grain; loose; this horizon has a thick layer
of cemented sand that could be penetrated with an auger; few sea
shells; common quartz grains; strongly alkaline, calcareous.
The mollic epipedon is 10 to 30 inches thick. Reaction throughout is
neutral to strongly alkaline.
The A horizon has hue of 10YR or 7.5YR, value and chroma of 2 or 3.

Estacion series
The Estacion series consists of fine loamy over sandy
or sandy-skeletal, mixed, isohyperthermic Fluventic
Hapludolls. These soils are shallow, are well drained, and
have an Ap horizon of dark brown silty clay loam and a C
horizon of very dark grayish brown gravelly clay loam
and sand. They formed in stratified moderately fine tex-
tured sediments over gravelly layers of mixed origin. The
Estacion soils are on river flood plains. Slopes range from
0 to 2 percent. The mean annual precipitation is 70 inches,
and the mean annual temperature is 80 degrees F.






SAN JUAN AREA, PUERTO RICO


The Estacion soils are associated with the Reilly, Toa,
Coloso, Bajura, and Dique soils. They are finer textured
in the upper horizons than the Reilly soils. They are
coarser textured than the Bajura soils. They have
gravelly subhorizons that the Toa, Coloso, and Dique soils
lack.
Typical pedon of Estacion silty clay loam, 0.5 mile
northwest from kilometer 32.8 of Highway 1, Caguas,
P.R.
Ap-O to 8 inches, dark brown (10YR 3/3) silty clay loam; moderate
medium granular structure; friable, slightly sticky, slightly plastic;
many fine roots; few subrounded gravel 1/2 to 2 inches in diameter;
medium acid; clear smooth boundary.
C1-8 to 20 inches, very dark grayish brown (10YR 3/2) gravelly clay
loam; weak fine subangular blocky structure; friable, slightly sticky,
slightly plastic; few fine roots; many fine and coarse gravel-size
subrounded fragments; medium acid; gradual smooth boundary.
C2-20 to 50 inches; dark brown (10YR 4/3) gravelly sand; single grain;
loose, nonsticky, nonplastic; about 50 percent coarse gravel; many
rounded cobbles 3 to 7 inches in diameter; slightly acid.
Reaction throughout is slightly acid to medium acid.
The A horizon has hue of 10YR or 7.5YR, value of 3, and chroma of 2
or 3.
The C horizons are gravelly clay loam and gravelly sand.

Guayama series
The Guayama series consists of clayey, mixed,
isohyperthermic Lithic Haplustalfs. These soils are shal-
low, are well drained, and have a B horizon of red
gravelly clay. They formed in residuum of volcanic rocks.
The Guayama soils are on side slopes and narrow
ridgetops of dissected uplands. Slopes range from 20 to 60
percent. The mean annual precipitation is 35 inches, and
the mean annual temperature is 80 degrees F.
The Guayama soils are associated with the
Descalabrado soils. The Guayama soils have a redder B
horizon than the Descalabrado soils.
Typical pedon of Guayama clay loam, 20 to 60 percent
slopes, 0.5 mile west from Jajome Bajo School, then 25
feet north from dirt road, Cayey, P.R.

A-0 to 4 inches, dark reddish brown (5YR 3/4) clay loam; weak fine
granular structure; slightly hard, friable, slightly sticky, slightly
plastic; common fine roots; common angular rock fragments 1/8 to 1
inch in diameter; neutral; clear smooth boundary.
B-4 to 12 inches, red (2.5YR 4/6) gravelly clay; weak fine and medium
subangular blocky structure; friable, slightly sticky, slightly plastic;
common fine roots; about 25 percent angular rock fragments 1/4 to
2 inches in diameter; neutral; clear smooth boundary.
C-12 to 20 inches, red (2.5YR 5/8) gravelly silty clay loam; massive; fri-
able, slightly sticky, slightly plastic; horizon consists of about 60
percent light yellowish brown (2.5Y 6/4) saprolite; about 25 percent
weathered rock fragments; neutral; clear smooth boundary.
R-20 inches; greenish colored consolidated volcanic rock.
The solum is 10 to 14 inches thick. Depth to consolidated rock is 20
inches or less. Reaction throughout is neutral to mildly alkaline.
The A horizon has hue of 7.5YR or 5YR, value of 3 or 4, and chroma
of 3 or 4.
The B horizon has hue of 5YR or 2.5YR, value of 3 or 4, and chroma
of 4 to 6.


Humacao series
The Humacao series consists of fine-loamy, mixed,
isohyperthermic Fluventic Eutropepts. These soils are
deep, are moderately well drained, and have a B horizon
of dark yellowish brown sandy clay loam. They formed in
medium and moderately fine textured sediments derived
from plutonic rocks. The Humacao soils are on terraces
above the river flood plains. Slopes range from 0 to 2 per-
cent. The mean annual precipitation is 85 inches, and the
mean annual temperature is 75 degrees F.
The Humacao soils are associated with the Candelero
and Vivi soils. The Humacao soils have a thinner and
coarser textured solum than the Candelero soils, but are
finer textured throughout than the Vivi soils.
Typical pedon of Humacao loam, 0.4 mile west from
kilometer 1.5 of Highway 912, then 18 feet north from
rectangular cattle drinking tank, Bo. Cerro Gordo, San
Lorenzo, P.R.
A-0 to 8 inches, dark brown (10YR 4/3) loam; weak fine granular struc-
ture; friable, nonsticky, nonplastic; many fine roots; common fine
quartz grains; few dark minerals; strongly acid; clear smooth boun-
dary.
B-8 to 15 inches, dark yellowish brown (10YR 4/4) sandy clay loam;
weak fine subangular blocky structure; friable, nonsticky, non-
plastic; few fine roots; common fine quartz grains; few dark concre-
tions; strongly acid; clear smooth boundary.
C1-15 to 26 inches, brown (7.5YR 5/4) clay loam; weak fine subangular
blocky structure; friable, nonsticky, slightly plastic; few fine roots;
common fine quartz grains; common fine dark minerals; few dark
concretions; strongly acid; clear smooth boundary.
C2-26 to 44 inches, strong brown (7.5YR 5/6) clay loam; weak fine sub-
angular blocky structure; friable, nonsticky, slightly plastic; few fine
roots; common fine quartz grains; common fine dark minerals; few
dark concretions; strongly acid; clear smooth boundary.
C3-44 to 60 inches, redddish yellow (7.5YR 6/6) sandy clay loam; mas-
sive; very friable, nonsticky, nonplastic; many quartz grains; few
dark minerals; strongly acid.
The solum is 13 to 24 inches thick. Reaction throughout is strongly
acid to medium acid.
The A horizon has hue of 10YR or 7.5YR, value of 2 to 4, and chroma
of 2 or 3.
The B horizon has hue of 10YR or 5YR, value of 4 to 6, and chroma of
3 to 8.
The C horizons are clay loam and sandy clay loam.

Humatas series
The Humatas series consists of clayey, kaolinitic,
isohyperthermic Typic Tropohumults. These soils are
deep, are well drained, and have a B2 horizon of red clay.
They formed in residuum of basic volcanic rocks. The Hu-
matas soils are on narrow ridgetops and side slopes.
Slopes range from 20 to 60 percent, but are dominantly 40
to 60 percent. The mean annual precipitation is 86 inches,
and the mean annual temperature is 76 degrees F.
The Humatas soils are associated with the Catalina,
Consumo, and Daguey soils. They have a thinner solum
than the Catalina and Daguey soils and a thicker B2
horizon than the Consumo soils. They are also associated
with the Naranjito soils, but are deeper than the Naran-
jito soils.






SAN JUAN AREA, PUERTO RICO


The Estacion soils are associated with the Reilly, Toa,
Coloso, Bajura, and Dique soils. They are finer textured
in the upper horizons than the Reilly soils. They are
coarser textured than the Bajura soils. They have
gravelly subhorizons that the Toa, Coloso, and Dique soils
lack.
Typical pedon of Estacion silty clay loam, 0.5 mile
northwest from kilometer 32.8 of Highway 1, Caguas,
P.R.
Ap-O to 8 inches, dark brown (10YR 3/3) silty clay loam; moderate
medium granular structure; friable, slightly sticky, slightly plastic;
many fine roots; few subrounded gravel 1/2 to 2 inches in diameter;
medium acid; clear smooth boundary.
C1-8 to 20 inches, very dark grayish brown (10YR 3/2) gravelly clay
loam; weak fine subangular blocky structure; friable, slightly sticky,
slightly plastic; few fine roots; many fine and coarse gravel-size
subrounded fragments; medium acid; gradual smooth boundary.
C2-20 to 50 inches; dark brown (10YR 4/3) gravelly sand; single grain;
loose, nonsticky, nonplastic; about 50 percent coarse gravel; many
rounded cobbles 3 to 7 inches in diameter; slightly acid.
Reaction throughout is slightly acid to medium acid.
The A horizon has hue of 10YR or 7.5YR, value of 3, and chroma of 2
or 3.
The C horizons are gravelly clay loam and gravelly sand.

Guayama series
The Guayama series consists of clayey, mixed,
isohyperthermic Lithic Haplustalfs. These soils are shal-
low, are well drained, and have a B horizon of red
gravelly clay. They formed in residuum of volcanic rocks.
The Guayama soils are on side slopes and narrow
ridgetops of dissected uplands. Slopes range from 20 to 60
percent. The mean annual precipitation is 35 inches, and
the mean annual temperature is 80 degrees F.
The Guayama soils are associated with the
Descalabrado soils. The Guayama soils have a redder B
horizon than the Descalabrado soils.
Typical pedon of Guayama clay loam, 20 to 60 percent
slopes, 0.5 mile west from Jajome Bajo School, then 25
feet north from dirt road, Cayey, P.R.

A-0 to 4 inches, dark reddish brown (5YR 3/4) clay loam; weak fine
granular structure; slightly hard, friable, slightly sticky, slightly
plastic; common fine roots; common angular rock fragments 1/8 to 1
inch in diameter; neutral; clear smooth boundary.
B-4 to 12 inches, red (2.5YR 4/6) gravelly clay; weak fine and medium
subangular blocky structure; friable, slightly sticky, slightly plastic;
common fine roots; about 25 percent angular rock fragments 1/4 to
2 inches in diameter; neutral; clear smooth boundary.
C-12 to 20 inches, red (2.5YR 5/8) gravelly silty clay loam; massive; fri-
able, slightly sticky, slightly plastic; horizon consists of about 60
percent light yellowish brown (2.5Y 6/4) saprolite; about 25 percent
weathered rock fragments; neutral; clear smooth boundary.
R-20 inches; greenish colored consolidated volcanic rock.
The solum is 10 to 14 inches thick. Depth to consolidated rock is 20
inches or less. Reaction throughout is neutral to mildly alkaline.
The A horizon has hue of 7.5YR or 5YR, value of 3 or 4, and chroma
of 3 or 4.
The B horizon has hue of 5YR or 2.5YR, value of 3 or 4, and chroma
of 4 to 6.


Humacao series
The Humacao series consists of fine-loamy, mixed,
isohyperthermic Fluventic Eutropepts. These soils are
deep, are moderately well drained, and have a B horizon
of dark yellowish brown sandy clay loam. They formed in
medium and moderately fine textured sediments derived
from plutonic rocks. The Humacao soils are on terraces
above the river flood plains. Slopes range from 0 to 2 per-
cent. The mean annual precipitation is 85 inches, and the
mean annual temperature is 75 degrees F.
The Humacao soils are associated with the Candelero
and Vivi soils. The Humacao soils have a thinner and
coarser textured solum than the Candelero soils, but are
finer textured throughout than the Vivi soils.
Typical pedon of Humacao loam, 0.4 mile west from
kilometer 1.5 of Highway 912, then 18 feet north from
rectangular cattle drinking tank, Bo. Cerro Gordo, San
Lorenzo, P.R.
A-0 to 8 inches, dark brown (10YR 4/3) loam; weak fine granular struc-
ture; friable, nonsticky, nonplastic; many fine roots; common fine
quartz grains; few dark minerals; strongly acid; clear smooth boun-
dary.
B-8 to 15 inches, dark yellowish brown (10YR 4/4) sandy clay loam;
weak fine subangular blocky structure; friable, nonsticky, non-
plastic; few fine roots; common fine quartz grains; few dark concre-
tions; strongly acid; clear smooth boundary.
C1-15 to 26 inches, brown (7.5YR 5/4) clay loam; weak fine subangular
blocky structure; friable, nonsticky, slightly plastic; few fine roots;
common fine quartz grains; common fine dark minerals; few dark
concretions; strongly acid; clear smooth boundary.
C2-26 to 44 inches, strong brown (7.5YR 5/6) clay loam; weak fine sub-
angular blocky structure; friable, nonsticky, slightly plastic; few fine
roots; common fine quartz grains; common fine dark minerals; few
dark concretions; strongly acid; clear smooth boundary.
C3-44 to 60 inches, redddish yellow (7.5YR 6/6) sandy clay loam; mas-
sive; very friable, nonsticky, nonplastic; many quartz grains; few
dark minerals; strongly acid.
The solum is 13 to 24 inches thick. Reaction throughout is strongly
acid to medium acid.
The A horizon has hue of 10YR or 7.5YR, value of 2 to 4, and chroma
of 2 or 3.
The B horizon has hue of 10YR or 5YR, value of 4 to 6, and chroma of
3 to 8.
The C horizons are clay loam and sandy clay loam.

Humatas series
The Humatas series consists of clayey, kaolinitic,
isohyperthermic Typic Tropohumults. These soils are
deep, are well drained, and have a B2 horizon of red clay.
They formed in residuum of basic volcanic rocks. The Hu-
matas soils are on narrow ridgetops and side slopes.
Slopes range from 20 to 60 percent, but are dominantly 40
to 60 percent. The mean annual precipitation is 86 inches,
and the mean annual temperature is 76 degrees F.
The Humatas soils are associated with the Catalina,
Consumo, and Daguey soils. They have a thinner solum
than the Catalina and Daguey soils and a thicker B2
horizon than the Consumo soils. They are also associated
with the Naranjito soils, but are deeper than the Naran-
jito soils.






SAN JUAN AREA, PUERTO RICO


The Estacion soils are associated with the Reilly, Toa,
Coloso, Bajura, and Dique soils. They are finer textured
in the upper horizons than the Reilly soils. They are
coarser textured than the Bajura soils. They have
gravelly subhorizons that the Toa, Coloso, and Dique soils
lack.
Typical pedon of Estacion silty clay loam, 0.5 mile
northwest from kilometer 32.8 of Highway 1, Caguas,
P.R.
Ap-O to 8 inches, dark brown (10YR 3/3) silty clay loam; moderate
medium granular structure; friable, slightly sticky, slightly plastic;
many fine roots; few subrounded gravel 1/2 to 2 inches in diameter;
medium acid; clear smooth boundary.
C1-8 to 20 inches, very dark grayish brown (10YR 3/2) gravelly clay
loam; weak fine subangular blocky structure; friable, slightly sticky,
slightly plastic; few fine roots; many fine and coarse gravel-size
subrounded fragments; medium acid; gradual smooth boundary.
C2-20 to 50 inches; dark brown (10YR 4/3) gravelly sand; single grain;
loose, nonsticky, nonplastic; about 50 percent coarse gravel; many
rounded cobbles 3 to 7 inches in diameter; slightly acid.
Reaction throughout is slightly acid to medium acid.
The A horizon has hue of 10YR or 7.5YR, value of 3, and chroma of 2
or 3.
The C horizons are gravelly clay loam and gravelly sand.

Guayama series
The Guayama series consists of clayey, mixed,
isohyperthermic Lithic Haplustalfs. These soils are shal-
low, are well drained, and have a B horizon of red
gravelly clay. They formed in residuum of volcanic rocks.
The Guayama soils are on side slopes and narrow
ridgetops of dissected uplands. Slopes range from 20 to 60
percent. The mean annual precipitation is 35 inches, and
the mean annual temperature is 80 degrees F.
The Guayama soils are associated with the
Descalabrado soils. The Guayama soils have a redder B
horizon than the Descalabrado soils.
Typical pedon of Guayama clay loam, 20 to 60 percent
slopes, 0.5 mile west from Jajome Bajo School, then 25
feet north from dirt road, Cayey, P.R.

A-0 to 4 inches, dark reddish brown (5YR 3/4) clay loam; weak fine
granular structure; slightly hard, friable, slightly sticky, slightly
plastic; common fine roots; common angular rock fragments 1/8 to 1
inch in diameter; neutral; clear smooth boundary.
B-4 to 12 inches, red (2.5YR 4/6) gravelly clay; weak fine and medium
subangular blocky structure; friable, slightly sticky, slightly plastic;
common fine roots; about 25 percent angular rock fragments 1/4 to
2 inches in diameter; neutral; clear smooth boundary.
C-12 to 20 inches, red (2.5YR 5/8) gravelly silty clay loam; massive; fri-
able, slightly sticky, slightly plastic; horizon consists of about 60
percent light yellowish brown (2.5Y 6/4) saprolite; about 25 percent
weathered rock fragments; neutral; clear smooth boundary.
R-20 inches; greenish colored consolidated volcanic rock.
The solum is 10 to 14 inches thick. Depth to consolidated rock is 20
inches or less. Reaction throughout is neutral to mildly alkaline.
The A horizon has hue of 7.5YR or 5YR, value of 3 or 4, and chroma
of 3 or 4.
The B horizon has hue of 5YR or 2.5YR, value of 3 or 4, and chroma
of 4 to 6.


Humacao series
The Humacao series consists of fine-loamy, mixed,
isohyperthermic Fluventic Eutropepts. These soils are
deep, are moderately well drained, and have a B horizon
of dark yellowish brown sandy clay loam. They formed in
medium and moderately fine textured sediments derived
from plutonic rocks. The Humacao soils are on terraces
above the river flood plains. Slopes range from 0 to 2 per-
cent. The mean annual precipitation is 85 inches, and the
mean annual temperature is 75 degrees F.
The Humacao soils are associated with the Candelero
and Vivi soils. The Humacao soils have a thinner and
coarser textured solum than the Candelero soils, but are
finer textured throughout than the Vivi soils.
Typical pedon of Humacao loam, 0.4 mile west from
kilometer 1.5 of Highway 912, then 18 feet north from
rectangular cattle drinking tank, Bo. Cerro Gordo, San
Lorenzo, P.R.
A-0 to 8 inches, dark brown (10YR 4/3) loam; weak fine granular struc-
ture; friable, nonsticky, nonplastic; many fine roots; common fine
quartz grains; few dark minerals; strongly acid; clear smooth boun-
dary.
B-8 to 15 inches, dark yellowish brown (10YR 4/4) sandy clay loam;
weak fine subangular blocky structure; friable, nonsticky, non-
plastic; few fine roots; common fine quartz grains; few dark concre-
tions; strongly acid; clear smooth boundary.
C1-15 to 26 inches, brown (7.5YR 5/4) clay loam; weak fine subangular
blocky structure; friable, nonsticky, slightly plastic; few fine roots;
common fine quartz grains; common fine dark minerals; few dark
concretions; strongly acid; clear smooth boundary.
C2-26 to 44 inches, strong brown (7.5YR 5/6) clay loam; weak fine sub-
angular blocky structure; friable, nonsticky, slightly plastic; few fine
roots; common fine quartz grains; common fine dark minerals; few
dark concretions; strongly acid; clear smooth boundary.
C3-44 to 60 inches, redddish yellow (7.5YR 6/6) sandy clay loam; mas-
sive; very friable, nonsticky, nonplastic; many quartz grains; few
dark minerals; strongly acid.
The solum is 13 to 24 inches thick. Reaction throughout is strongly
acid to medium acid.
The A horizon has hue of 10YR or 7.5YR, value of 2 to 4, and chroma
of 2 or 3.
The B horizon has hue of 10YR or 5YR, value of 4 to 6, and chroma of
3 to 8.
The C horizons are clay loam and sandy clay loam.

Humatas series
The Humatas series consists of clayey, kaolinitic,
isohyperthermic Typic Tropohumults. These soils are
deep, are well drained, and have a B2 horizon of red clay.
They formed in residuum of basic volcanic rocks. The Hu-
matas soils are on narrow ridgetops and side slopes.
Slopes range from 20 to 60 percent, but are dominantly 40
to 60 percent. The mean annual precipitation is 86 inches,
and the mean annual temperature is 76 degrees F.
The Humatas soils are associated with the Catalina,
Consumo, and Daguey soils. They have a thinner solum
than the Catalina and Daguey soils and a thicker B2
horizon than the Consumo soils. They are also associated
with the Naranjito soils, but are deeper than the Naran-
jito soils.







SOIL SURVEY


Typical pedon of Humatas clay, 40 to 60 percent slopes,
0.9 mile from kilometer 9.8 of Highway 765 and 200 feet
northwest from dirt road, San Lorenzo, P.R.
Ap-0 to 5 inches, dark brown (7.5YR 4/4) clay; weak fine subangular
blocky structure; friable, slightly sticky, slightly plastic; common
fine roots; few fine pores; few fine black concretions; few
krotovinas; very strongly acid; clear smooth boundary.
B21t-5 to 14 inches; red (2.5YR 4/6) clay; moderate medium subangular
blocky structure; friable, slightly sticky, plastic; few fine roots; few
fine pores; few fine black concretions; common thin clay films on
surfaces of peds and in pores; very strongly acid; clear smooth
boundary.
B22t-14 to 24 inches, red (2.5YR 4/6) clay, few yellowish brown (10YR
5/4) mottles; moderate medium subangular blocky structure; friable,
slightly sticky, plastic; few fine pores; common thin clay films on
surfaces of peds and in pores; very strongly acid; gradual smooth
boundary.
B3-24 to 34 inches, yellowish red (5YR 5/6) silty clay, few fine dark
yellowish brown (10YR 4/4), red (10R 4/6), yellowish brown (10YR
5/6), and dusky red (2.5YR 3/4) mottles; weak fine and medium sub-
angular blocky structure; friable, nonsticky, slightly plastic; few thin
clay films; 2 percent weathered rock fragments; very strongly acid;
clear smooth boundary.
C1-34 to 45 inches, red (10R 4/8), yellowish red (5YR 5/6), and strong
brown (7.5YR 5/6) silty clay; massive; very friable, nonsticky,
slightly plastic; few fine pores; 2 percent weathered rock frag-
ments; 75 percent of horizon is saprolite; strongly acid; gradual
smooth boundary.
C2-45 to 60 inches, dark red (10R 3/6), red (10R 4/6), reddish brown
(5YR 5/4), olive yellow (2.5Y 6/8), and white (N 8/0) silty clay
saprolite; massive; very friable, nonsticky, slightly plastic; few fine
pores; 2 percent weathered rock fragments; strongly acid.
The solum is 23 to 41 inches thick. Reaction throughout is very
strongly acid or strongly acid.
The A horizon has hue of 5YR or 7.5YR, value of 3 to 5, and chroma
of 4 to 6.
The B2t horizon has hue of 2.5YR or 5YR, value of 4 to 6, and chroma
of 3 to 6. It has weak to moderate fine and medium subangular blocky
structure.
The C horizon is silty clay, clay, or clay loam.

Jagueyes series

The Jagueyes series consists of fine-loamy, mixed,
isohyperthermic Orthoxic Tropudults. These soils are
deep, are well drained, and have a B2t horizon of red clay
loam. They formed in residuum of plutonic rocks. The
Jagueyes soils are on side slopes and narrow ridgetops of
humid uplands. Slopes range from 20 to 40 percent. The
mean annual precipitation is 80 inches, and the mean an-
nual temperature is 80 degrees F.
The Jagueyes soils are associated with the Lirios,
Limones, and Pandura soils. The Jagueyes have thicker
and redder B2 horizons than the Pandura soils. They are
coarser textured than Limones soils and have a thicker
solum than Lirios soils.
Typical pedon of Jagueyes loam, 20 to 40 percent
slopes, eroded, 2.8 miles southeast of kilometer 11.4 of
Highway 181, then 350 feet southwest from dirt road,
then 50 feet west, San Lorenzo, P.R.
Ap-0 to 5 inches, dark yellowish brown (10YR 4/4) loam; few fine gray-
ish brown (2.5Y 5/2) mottles; weak fine subangular blocky structure
parting to granular; friable, nonsticky, nonplastic; few fine roots;
common fine quartz grains; few fine black concretions; few
krotovinas; very strongly acid; clear smooth boundary.


B21t-5 to 14 inches, yellowish red (5YR 4/6) and yellowish brown
(10YR 5/6) clay loam; weak fine and medium subangular blocky
structure; friable, slightly sticky, slightly plastic; few fine roots; few
fine pores; few patchy clay films; common quartz grains; few fine
black concretions; few krotovinas; very strongly acid; clear smooth
boundary.
B22t-14 to 24 inches, red (2.5YR 4/6) clay loam; common medium
distinct light yellowish brown (10YR 6/4) mottles; moderate medium
subangular blocky structure; firm, slightly sticky, slightly plastic;
few fine roots; few fine pores; common patchy clay films; common
fine quartz grains; few dark concretions; very strongly acid; gradual
smooth boundary.
B23t-24 to 41 inches; red (2.5YR 4/6) clay loam; few medium distinct
light yellowish brown (10YR 6/4) mottles; moderate meeedium suban-
gular blocky structure; firm, slightly sticky, slightly plastic; few fine
pores; common patchy clay films, many fine quartz grains; few
black concretions; very strongly acid; gradual smooth boundary.
B3-41 to 54 inches, red (2.5YR 4/8) sandy clay loam; common medium
distinct brownish yellow (10YR 6/6) and few medium distinct light
gray (10YR 7/2) mottles; weak fine subangular blocky structure; fri-
able, nonsticky, slightly plastic; few fine pores; many fine quartz
grains; few fine black minerals; very strongly acid; clear smooth
boundary.
C-54 to 62 inches, yellowish red (5YR 5/8) sandy clay loam; mottles are
many fine distinct pink (7.5YR 7/4), common fine distinct very pale
brown (10YR 7/4), and few fine red (2.5YR 4/8); weak fine subangu-
lar blocky structure; friable, nonsticky, slightly plastic; many fine
quartz grains; few fine black minerals; about 75 percent of horizon
is saprolite; very strongly acid.
The solum is 48 to 60 inches thick. Reaction throughout is very
strongly acid.
The A horizon has hue of 10YR or 7.5YR, value of 2 to 4, and chroma
of 2 to 4.
The B2t horizon has hue of 5YR or 2.5YR, value of 4 to 7, and chroma
of 6 to 8. It has weak to moderate fine to medium subangular blocky
structure.

Juncal series

The Juncal series consists of fine, mixed, isohyperther-
mic Typic Tropudalfs. These soils are deep, are moderate-
ly well drained, and have B2t horizons of dark yellowish
brown, brownish yellow, and yellowish brown clay. They
formed in residuum of limestone. The Juncal soils are on
foot slopes and low rounded hills. Slopes range from 5 to
20 percent. The mean annual precipitation is 85 inches,
and the mean annual temperature is 77 degrees F.
The Juncal soils are associated with the Colinas soils.
They are thicker and have yellower and lighter colors
than the Colinas soils.
Typical pedon of Juncal clay, 5 to 20 percent slopes,
eroded, 1.9 kilometers south of junction of Highways 2
and 677, 2.5 kilometers east of junction of Highways 823
and 677, 1700 feet northeast of a dairy barn, 800 feet
northeast of a farm pond, Barrio Rio Lajas, Toa Alta,
P.R.

Ap-0 to 10 inches, dark grayish brown (10YR 4/2) clay; weak coarse
subangular blocky structure; firm, slightly sticky, plastic; many fine
roots; medium acid; clear wavy boundary.
B21t-10 to 14 inches, dark yellowish brown (10YR 4/4) clay; moderate
medium subangular blocky structure; firm, slightly sticky, plastic;
thin patchy clay films; common fine roots; mildly alkaline; clear
wavy boundary.
B22t-14 to 20 inches, yellowish brown (10YR 5/6) clay; moderate medi-
um subangular blocky structure; firm, slightly sticky, plastic; thin
discontinuous patchy clay films; few fine roots; mildly alkaline; clear
wavy boundary.




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