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Title: Chemical studies on soils from Florida citrus groves
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Title: Chemical studies on soils from Florida citrus groves
Physical Description: Book
Creator: Peech, Michael
Publisher: University of Florida Agricultural Experiment Station
Publication Date: 1948
Copyright Date: 1948
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Table of Contents
    Title Page
        Page 1
    Front Matter
        Page 2
        Page 3
    Table of Contents
        Page 4
    Main
        Page 5
        Page 6
        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
        Page 36
        Page 37
        Page 38
        Page 39
        Page 40
        Page 41
        Page 42
        Page 43
        Page 44
        Page 45
        Page 46
        Page 47
        Page 48
        Page 49
        Page 50
        Page 51
        Page 52
        Page 53
        Page 54
        Page 55
        Page 56
    Literature cited
        Page 57
        Page 58
        Page 59
        Page 60
        Page 61
    Appendix
        Page 62
        Page 63
        Page 64
        Page 65
        Page 66
        Page 67
        Page 68
        Page 69
        Page 70
        Page 71
        Page 72
        Page 73
        Page 74
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Full Text



bulletin 448 September, 1948
(A Revision of Bulletin 340)

UNIVERSITY OF FLORIDA
AGRICULTURAL EXPERIMENT STATIONS
HAROLD MOWRY, Director
GAINESVILLE, FLORIDA














CHEMICAL STUDIES ON SOILS

FROM FLORIDA CITRUS GROVES

By MICHAEL PEECH
Revised by T. W. YOUNG


















Single copies free to Florida residents on request to
AGRICULTURAL EXPERIMENT STATION
GAINESVILLE, FLORIDA










BOARD OF CONTROL ECONOMICS, AGRICULTURAL
C. V. Noble, Ph.D., Agri. Economists
J. Thos. Gurney, Chairman, Orlando Zach Nole, hM..A., As economist
N. B. Jordan, Quincy acH. Spurlock, M.S.A., Associate
Thos. W. Bryant, Lakeland A. H. Surlock, M.S., Associate
J. Henson Markham, Jacksonville D. Brooke, M.S., Associate
Hollis Rinehart, Miami D. L. Brooke, M.S.A., Associate
W. F. Powers, Secretary, TallahasseR. E. L. Greene, Ph.D., Agri. Economist
W. F. Powers, Secretary, Tallahassee H. W. Little, M.S., Assistant
H. W. Little, M.S., Assistant

EXECUTIVE STAFF Orlando, Florida (Cooperative USDA)

J. Hillis Miller, Ph.D., President of the G. Norman Rose, B.S., Asso. Agr. Economist
University3 J. C. Townsend, Jr., B.S.A., Agr. Statistician2
H. Harold Hume, D.Sc., Provost for Agr.' J. B. Owens, B.S.A., Agr. Statistician2
Harold Mowry, M.S.A., Director J. F. Steffens, Jr., B.S.A., Agr. Statisticians
L. O. Gratz, Ph.D., Asst. Dir., Research
W. M. Fifield, M.S., Asst. Dir., Admin. ECONOMICS, HOME
J. Francis Cooper, M.S.A., Editors Ouida D. Abbott, Ph.D., Home Econ.1
Clyde Beale, A.B.J., Associate Editors R. B. French, Ph.D., Biochemist
Ida Keeling Cresap, Librarian
Ruby Newhall, Administrative Manager3 ENTOMOLOGY
Geo. F. Baughman, M.A., Business Manager' A. N. Tissot, Ph.D. Entomologist'
Claranelle Alderman, Accountant L. C. Kuitert, Ph.D., Assistant
H. E. Bratley, M.S.A., Assistant
MAIN STATION, GAINESVILLE
HORTICULTURE
AGRICULTURAL ENGINEERING G. H. Blackmon, M.S.A., Horticulturist'
Frazier Rogers, M.S.A., Agr. Engineers F. S. Jamison, Ph.D., Horticulturists
J. M. Johnson, B.S.A.E., Asso. Agr. Engineers H. M. Reed, B.S., Chem., Veg. Processing
J. M. Myers, B.S., Asso. Agr. Engineer Byron E. Janes, Ph.D., Asso. Hort.
R. E. Choate, B.S.A.E., Asst. Agr. Engineers R. A. Dennison, Ph.D., Asso. Hort.
A. M. Pettis, B.S.A.E., Asst. Agr. Engineers R. K. Showalter, M.S., Asso. Hort.
Albert P. Lorz, Ph.D., Asso. Hort.
AGRONOMY R. H. Sharpe, M.S., Asso. Hort.
Fred H. Hull, Ph.D., Agronomist1 R. J. Wilmot, M.S.A., Asst. Hort.
G. E. Ritchey, M.S., Agronomists R. D. Dickey, M.S.A., Asst. Hort.
G. B. Killinger, Ph.D., Agronomists Victor F. Nettles, M.S.A., Asst. Hort.'
H. C. Harris, Ph.D., Agronomist3 F. S. Lagasse, Ph.D., Asso. Hort.2
R. W. Bledsoe, Ph.D., Agronomist L. H. Halsey, B.S.A., Asst. Hort.
M. E. Paddick, Ph.D., Agronomist F. E. Myers, B.S.A., Asst. Hort.
S. C. Litzenberger, Ph.D., Associate
W. A. Carver, Ph.D., Associate PLANT PATHOLOGY
Frej A. Clark, B.S., Assistant W. B. Tisdale, Ph.D., Plant Pathologist'
Phares Decker, Ph.D., Asso. Plant Path.
ANIMAL INDUSTRY Erdman West, M.S., Mycologist and Botanist
A. L. Shealy, D.V.M., An. Industrialist' Howard N. Miller, Ph.D., Asso. Plant Path.
R. B. Becker, Ph.D., Dairy Husbandmans Lillian E. Arnold, M.S., Asst. Botanist
E. L. Fouts, Ph.D., Dairy Technologist3 SOILS
D. A. Sanders, D.V.M., Veterinarian
M. W. Emmel, D.V.M. Veterinarian3 F. B. Smith, Ph.D., Microbiologist 3
Gaylord M. Volk, Ph.D., Chemist
L. E. Swanson, D.V.M., Parasitologist J. R. Henderson, M.S.A., Soil Technologists
N. R. Mehrhof, M.Agr., Poultry Husb.' J. R. Neller, Ph.D., Soils Chemist
G. K. Davis, Ph.D., Animal Nutritionists Nathan Gammon, Jr., Ph.D., Soils Chemist
C. E. Bell, Ph.D., Associate Chemist
R. S. Glasscock, Ph.D., An. Husbandman3 R. Carrigan, Ph.D., Asso. Biochemists
P. T. Dix Arnold, M.S.A., Asst. Dairy Hush.8 H. W. Winsor, B.S.A., Assistant Chemist
L. E. Mull, M.S., Asst. in Dairy Tech. Geo. D. Thornton, Ph.D., Asso. Microbiologists
R. E. Caldwell, M.S.A., Asst. Chemists
Katherine Boney, B.S., Asst. Chem. J. B. Cromartie, B.S.A., Soil Surveyor
J. C. Driggers, B.S.A., Asst. Poultry Husb.3 Ralph G. Leighty, B.S., Asso. Soil Surveyor
Glenn Van Ness, D.V.M., Asso. Poultry V. W. Cyzycki, B.S., Asst. Soil Surveyor
Pathologist R. B. Forbes, M.S., Asst. Soils Chemist
S. John Folks, B.S.A., Asst. An. Hush. W. L. Prithett, M.S., Asst. Chemistyor
Jean Beem, B.S.A., Asst. Soil Surveyor
W. A. Krienke, M.S., Asso. in Dairy Mfs.3
S. P. Marshall, Ph.D., Asso. Dairy Husb.3 1Head of Department.
C. F. Simpson, D.V.M., Asso. Veterinarian In cooperation with U. S.
C. F. Winchester, Ph.D., Asso. Biochemists 3 Cooperative, other divisions, U. of F.
C. L. Comar, Ph.D., Biochemist 4 On leave.










BRANCH STATIONS C. B. Savage, M.S.A., Asst. Horticulturist
D. L. Stoddard, Ph.D., Asso. Plant Path.
NORTH FLORIDA STATION, QUINCY
J. D. Warner, M.S.. Vice-Director in Charge SUB-TROPICAL STATION, HOMESTEAD
R. R. Kincaid, Ph.D., Plant Pathologist
W. H. Chapman, M.S., Asso. Agron. Geo. D. Ruehle, Ph.D., Vice-Dir. in Charge
R. C. Bond, M.S.A., Asso. Agronomist I. O. Wolfenbarger, Ph.D., Entomologist
L. G. Thompson, Ph.D., Soils Chemist Francis B. Lincoln, Ph.D., Horticulturist
Frank S. Baker, Jr., B.S., Asst. An. Husb. Robt. A. Conover, Ph.D., Asso. Plant Path.
Kelvin Dorward, M.S., Entomologist R. W. Harkness, Ph.D., Asst. Chemist
Milton Cobin, B.S., Asso. Horticulturist
Mobile Unit, Monticello
R. W. Wallace, B.S., Associate Agronomist W. CENT. FLA. STATION, BROOKSVILLE
William Jackson, B.S.A., Animal Husband-
Mobile Unit, Marianna man in Charge2
R. W. Lipscomb, M.S., Associate Agronomist

Mobile Un, Wew a RANGE CATTLE STATION, ONA
Mobile Unit, Wewahitchka
J. B. White, B.S.A., Associate Agronomist W. G. Kirk, Ph.D., Vice-Director in Charge
E. M. Hodges, Ph.D., Associate Agronomist
Mobile Unit, DeFuniak Springs D. W. Jones, B.S., Asst. Soil Technologist
H. J. Fulford, B.S.A. Asst. Animal Husb.
R. L. Smith, M.S., Associate Agronomist

CITRUS STATION, LAKE ALFRED CENTRAL FLORIDA STATION, SANFORD
A. F. Camp, Ph.D., Vice-Director in Charge R. W. Ruprecht, Ph.D., Vice-Dir. in Charge
W. L. Thompson, B.S., Entomologist J. W. Wilson, Sc.D., Entomologist
J. T. Griffiths, Ph.D., Asso. Entomologist Ben F. Whitner, Jr., B.S.A., Asst. Hort.
R. F. Suit, Ph.D., Plant Pathologist
E. P. Ducharme, M.S., Plant Pathologist' WEST FLORIDA STATION, MILTON
R. K. Voorhees, Ph.D., Asso. Horticulturist
C. R. Stearns, Jr., B.S.A., Asso. Chemist H. W. Lundy, B.S.A., Associate Agronomist
James K. Colehour, M.S., Asst. Chemist
T. W. Young, Ph.D., Asso. Horticulturist FIELD STATIONS
J. W. Sites, M.S.A., Horticulturist
H. O. Sterling, B.S., Asst. Horticulturist Leesburg
J. A. Granger, B.S.A., Asst. Horticulturist G. K. Parris, Ph.D., Plant Path. in Charge
H. J. Reitz, M.S., Asso. Horticulturist
Francine Fisher, M.S., Asst. Plant Path. Plant City
I. W. Wander, Ph.D., Soils Chemist
A. Wilson, B.S.A., Ass. Biochemist A. N. Brooks, Ph.D., Plant Pathologist
J. W. Kesterson, M.S., Asso. Chemist
R. N. Hendrickson, B.S., Asst. Chemist Hastings
E. H. Biteover, M.A., Soils Chemist A. H. Eddins, Ph.D., Plant Path. in Charge
Joe P. Barnett, B.S.A., Asst. Horticulturist E. N. McCubbin, Ph.D., horticulturist
J. C. Bowers, B.S., Asst. Chemist
D. S. Prosser, Jr., B.S., Asst. Horticulturist Monticello
R. W. Olsen, B.S., Biochemist A. M. Phillips, B.S., Asso. Entomologist2
F. W. Wenzel, Jr., Ph.D., Supervisory Chem.
Bradenton
EVERGLADES STATION, BELLE GLADE J. R. Beckenbach, Ph.D., Hort. in Charge
E. G. Kelsheimer, Ph.D., Entomologist
R. V. Allison, Ph.I., Vice-Director in Charge ee oo
Dav:d G. Kelbert, Asso. Horticulturist
F. D. Stevens, B.S., Sugarcane Agronomist L. Spencer, Ph.D., Soils Chemist
E. L. Spencer, Ph.D., Soils Chemist
Thomas Bregger, Ph.D., Sugarcane
Physiologist Robert O. Magie, Ph.D., Gladioli Hort.
J. W. Randolph, M.S., Agricultural Engineer J. M. Walter, Ph.D., Plant Pathologist
W. T. Forsee, Jr., Ph.D., Chemist Donald S. Burgis, M.S.A., Asst. Hort.
R. W. Kidder, M.S., Asso. Animal Husb.
T. C. Erwin, Assistant Chemist Lakeland
Roy A. Bair, Ph.D., Agronomist Warren O. Johnson, B.S., Meteorologist2
C. C. Seale, Asso. Agronomist
N. C. Hayslip, B.S.A., Asso. Entomologist 1 Head of Department.
E. H. Wolf, Ph.D., Asst. Horticulturist 2 In cooperation with U. S.
W. H. Thames, M.S., Asst. Entomologist 3 Cooperative, other divisions, U. of F.
J. C. Hoffman, M.S., Asso. Horticulturist On leave.











CONTENTS

Page

DESCRIPTION OF SOILS ............... ... ..... .... .. ......... 6

COLLECTION AND PREPARATION OF SAMPLES ..................... .......--..... 10

METHODS OF ANALYSIS .-............... .................----- ------------ ---11

RESULTS OF CHEMICAL ANALYSES ................--.. ------------------... 14

EXCHANGE CAPACITY AND THE DEGREE OF BASE SATURATION .-----................... 15

EXCHANGEABLE BASES ---....-...... --.. --..-..---.--------------------------- 21

Calcium ...-............. .................. .. --- -..... ....... 21

Magnesium ............- ...-... .. ...- ..........-----..... --- 22

Potassium ....----... .--- -.... --- ..-----------. -------------- .. 25

Manganese .......--..------ ....-- .-- .... --- .--.. ---..----. ------ ---------- 27

Copper .....---- --........ ...-..-- --..- -----. .-------- ------------ 31

Zinc ........-.......-..- ..-- ------------ --------------- .- -----------. 33

ORGANIC MATTER ............... ----...-.. ..... .......- ... ------ 37

TOTAL NITROGEN, NITRATE NITROGEN, AND THE C:N RATIO ..................... 39

ACID-SOLUBLE AND WATER-SOLUBLE PHOSPHORUS ....................................... 42

COMPARISON OF SOME GROVE SOILS WITH THE ADJOINING VIRGIN SOILS.... 48

VOLUME WEIGHTS OF SOIL ......-..........---..--...----..-------.... --------- 49

GENERAL DISCUSSION -..-..-----......-..-..-----.--. --- ------..-.---------.----- 50

SUMMARY ....-----........... ............. ...... ...... ------- ------------ 53

LITERATURE CITED .- .. ......- ...- ...... ---- --. ---------- ...- ..- ..--- ---..- ....... 57

APPENDIX ..........-...--- -----------............. ----- ------------. 62

Table 1 ....- -. .... ....... .... .... .. .. ..... ..... ----- ---- -----.----.. 62

Table 2 ....-........ ......-------- --.. .... .... ------ --------- 70

Table 3 .... .-- .............--------------------- ----- ------------- 72

Table 4 .......--. .....---. -. - ........... .. .... ......-- ...... --- 84










CHEMICAL STUDIES ON SOILS FROM FLORIDA
CITRUS GROVES
By MICHAEL PEECH 1
Revised by T. W. YOUNG

Although it is generally conceded among citrus growers of
Florida that certain soils are more fertile than others, very
little systematic information is available regarding the variation
in chemical composition of the different groups of soils planted
*to citrus or the extent of the variation within a given group
or series. A knowledge of the chemical composition of grove
soils not only is of importance to proper fertilization and soil
management but such information should prove invaluable to
a better understanding of some of the important grove problems
associated with the various soils. For the interpretation and
practical application of such information it is essential that one
have an appreciation of the natural variations existing among
and within the various soil groups. The importance of the in-
fluence of such controlling factors as fertilizer applications and
rainfall or irrigation, with respect to time of sampling, on the
amounts of certain soil constituents found in a given soil at
any specific time must also be recognized.
The main purpose of this publication is to present chemical
data on representative soil types and in a general way to evalu-
ate fertility of the various groups of soils planted to citrus on
the basis of their chemical composition.
The soils included in these studies were collected in two dif-
ferent surveys. The first survey was conducted in 1937 (49).2
On this survey detailed notes were made by Walter Reuther of
the Citrus Experiment Station staff in regard to the past fertil-
izer practices and the grove condition at the time the samples
were taken. This survey included 93 groves and 4 virgin tracts
located in various Florida citrus areas. It covered a wide range
of grove conditions on different soil types, but with a large
majority of samples being taken from groves on the light sandy
soils of the interior citrus areas. The soils of the coastal citrus
areas are, in general, of a somewhat heavier texture and a larger
portion of them are influenced by calcareous materials in the

1Peech: formerly Soils Chemist, Citrus Experiment Station.
Young: Associate Horticulturist, Citrus Experiment Station.
Italic figures in parentheses refer to "Literature Cited" on page 57.







6 Florida Agricultural Experiment Stations

subsoils than those of the interior. Since the 1937 survey included
only a relatively small number of coastal groves, which did not
thoroughly represent the great variety of soils in these areas, a
second survey was made during 1942-46 by T. W. Young. In
this later survey soil samples were collected from 111 groves,
as well as 4 previously farmed areas and 12 virgin tracts being
considered for citrus, in the coastal counties of Volusia, Brevard,
Indian River, St. Lucie, Martin, Palm Beach, Broward and Mon-
roe. As with the earlier survey, detailed notes were made of
grove conditions and past fertilizer practices.

DESCRIPTION OF SOILS 3
The soils planted to citrus in Florida may be divided into two
major groups: (1) well drained soils and (2) imperfectly to
poorly drained soils. According to the classification established
by the Bureau of Plant Industry, Soils and Agricultural Engi-
neering of the United States Department of Agriculture, soils are
grouped into series on the basis of origin, color, structure and
other characteristics. The series are further subdivided into
types according to the relative amounts of sand, silt and clay
in the surface layer or to the depth of the clay subsoil. Thus,
Norfolk fine sand and Norfolk sand, which differ mainly in the
texture of the surface layer, are different types belonging to
the Norfolk series.4

WELL DRAINED SOILS
The principal soils planted to citrus within the well drained
groups belong to the following series: Norfolk, Blanton, Eustis,
Lakewood, Orlando and Gainesville. The well drained and roll-
ing uplands, commonly referred to as "high pineland" in the
Ridge section and other parts of central Florida, are by far the
predominant soils used for citrus in the state, having been
planted extensively during the period of heaviest development
of citrus, and constitute at least 70 percent of the present total
acreage. Because of their excellent cold protection due to proper
air drainage they are highly prized soils for this purpose, al-
though their natural fertility is very low. In the natural state
these soils support a forest growth consisting of longleaf pine
(Pinus australis Michx. f.), live oak (Quercus virginiana Mill.),

"Prepared by J. R. Henderson, Soil Technologist, University of Florida.
SIf the soils used in this study were reclassified several new series
might be recognized and a number of the type names might be changed.







Chemical Studies on Soils from Florida Citrus Groves 7

turkey oak (Q. cinerea Michx.), and blackjack oak (Q. laevis
Walt.), the type of growth being more or less indicative of the
natural fertility of the soil. The better grades of soils in this
group (high pineland) show a preponderance of longleaf pine
and turkey oak with a few scattered live oaks, while the principal
growth on the poorer soils (commonly called "blackjack-oak
land" and "scrub land") consists of blackjack oaks or sand pine
(P. clause (Engelm.) Vasey.) and scrub oaks (Q. Chapmanii,
Q. Rolfsii, Q. myrtifolia and Q. geminata). Some of the best
soils within the group (Norfolk fine sand, hammock phase;
Eustis fine sand, dark-colored phase; Orlando fine sand and
Gainesville fine sand), locally known as "high-hammock land,"
support predominantly a rather heavy hardwood-hammock
growth, which consists principally of longleaf pine, live oak,
hickory (Hicoria spp.), magnolia (Magnolia grandiflora L.),
laurel oak (Q. laurifolia Michx.), and red oak (Q. rubra L.).
The surface layer of soil is usually thicker and darker, due to
the higher organic matter content, and consequently the fertility
of these soils is naturally higher than that of the soils of the
high pinelands.
The soils in this group are distinguished primarily by their
color characteristics. The Norfolk soils, which are dominant
in the high pine land and blackjack oak land, are characterized
by 4 to 6 inches of yellowish-gray or gray sand underlain by
pale yellow to yellow sand which extends to depths of from
2 to 20 or more feet, where friable yellow to yellowish-red
friable sandy clay is encountered. The Blanton soils, which
occupy lower areas within the Norfolk soils or knolls in the
"flatwoods," consist of 4 to 6 inches of gray sand underlain by
light gray and yellow splotched sand which passes into yellow
and gray mottled friable sandy clay at depths ranging from
3 to 20 or more feet. The Eustis soils, common in both the high
pine land and the high hammock land, consist of 5 to 7 inches
of brownish-gray to dark grayish-brown sand underlain by
reddish-yellow to yellowish-red sand which rests on friable
sandy clay at depths of 5 to 15 or more feet. The Lakewood
soils, representing the scrub land, have a surface layer of light
gray sand 2 to 4 inches in depth which gives way abruptly to
a layer of white sand 8 to 20 inches deep. This is underlain by
bright yellow sand which may extend to depths of 10 or more
feet without change. The Orlando and Gainesville soils are
found principally in the high hammocks. The former have dark







8 Florida Agricultural Experiment Stations

gray surfaces 8 to 12 inches in thickness, underlain by light
grayish-yellow to yellow sand, which may rest upon friable
yellow and gray mottled sandy clay at depths of 5 or more feet.
The latter have brownish-gray to grayish-brown surface layers
6 to 8 inches in thickness underlain by reddish-brown to brown-
ish-red sands which rest upon pebbly phosphatic brownish-red
sandy clay at depths of 3 to 5 feet.
IMPERFECTLY TO POORLY DRAINED SOILS
The important soils in this group planted to citrus occur
mainly along the East and West Coasts but also to some extent
in other areas over the Florida peninsula; and are commonly
referred to as "low hammocks," "palmetto flatwoods," "grassy
flatwoods" and "prairies," depending upon vegetative growth,
drainage conditions and topography.
The low hammocks are characterized by a heavy growth of
live oak, water oak (Q. nigra L.), cedar (Sabina silicicola
Small.), hickory, magnolia, swamp maple (Rufacer rubrum
L.), ash (Fraxinus spp.), sweet gum (Liquidambar styraciflua
L.), cabbage palmetto (Sabal palmetto (Walt.) Todd), and slash
pine (P. palustris Mill. and P. caribaea Morelet in South Flor-
ida) with an undergrowth of shrubs, the type of growth being
dependent to some extent on the soil type and the latitude.
The soils in these hammocks belong to three series: Park-
wood,5 Manatee and Bradenton. The dominant growth on the
Parkwood soils consists of live oak and cabbage palmetto, that
on the Manatee soils of maple and ash, and that on the Braden-
ton soils of live oak and slash pine. These soils are all underlain
by marl at varying depths, usually within 3 feet of the surface.
In areas where the marl substratum is so near the surface that
it becomes mixed with the surface material, deficiencies of zinc,
manganese and iron may become serious, resulting in a very
poor grove condition. The surface layer of the Parkwood soils
is gray to dark gray and may rest upon the marl or be separated
from it by a light gray sandy layer. The Manatee soils are dark
gray to black in the surface layer, which is separated from the
marl by a light gray calcareous sandy clay or clay. The Braden-
ton soils have a gray surface layer which is rather sandy. At
depths of 6 to 8 inches this passes into light sandy material
which is separated from the marl by a layer of acid gray, yellow
and brown mottled sandy clay.
5The Parkwood series, as considered in the 1937 survey, has now been
divided into three series: Parkwood, Manatee and Bradenton.








Chemical Studies on Soils from Florida Citrus Groves 9

The principal soils of the palmetto flatwoods which are planted
to citrus are included in the Leon, Immokalee, Broward and
Sunniland series. All of these soils support a forest growth of
slash and longleaf pine and an undergrowth of saw palmetto
(Serenoa repens (Bartr.) Small) and wiregrass (Aristida spp.
and Sporalulies spp.). The surface layers of all these soils are
gray but they may be distinguished easily by the subsoils. The
subsoil of the Sunniland soils is a gray and yellow mottled cal-
careous sandy clay, whereas those of Leon and Immokalee are
dark brown or black organic "hardpans." The hardpan is well
developed in the Leon soils and occurs at depths of 12 to 30
inches, while in the Immokalee soils it is poorly developed and
occurs at depths of 30 to 40 inches. The Broward soils have
a substratum of limestone beneath sandy soil material.
The soils of the grassy flatwoods that are planted to citrus
belong mainly in the Bladen and Portsmouth series. The Bladen
soils have a 6- to 8-inch surface of gray loamy sand resting
upon light gray loamy sand which in turn rests at a depth of
12 to 40 inches upon gray and yellow mottled plastic acid sandy
clay. The Portsmouth soils have dark to black sand surfaces
over light gray sand which extends to depths of 3 feet or more.
The native growth on these soils consists of longleaf and slash
pine and wiregrass.
The soils of the prairies planted to citrus are included in the
following series: Felda, Charlotte, Arzell, Delray and Davie.
With the exception of the Davie soils, on which the native growth
is sawgrass (Mariscus jamaicensis (Crantz) Britton), these
soils are naturally covered with a wide variety of grasses, sedges
and herbaceous aquatic plants.
Surface layers of Arzell and Charlotte soils are light gray,
of Felda gray, and of Delray dark gray to black. Subsoil of
Arzell soils are almost white, those of Charlotte bright yellow,
those of Felda and Delray light gray. Calcareous sandy clay
may be encountered in all of them at various depths-usually
below 3 feet in Charlotte and Arzell and less than 3 feet in
Felda and Delray. Davie soils, locally called "muck," occur
along the edges of the Everglades and were at one time covered
by a thin layer of peat. This peat layer is now in various degrees
of disappearance; remaining as a black peat layer in some in-
stances, forming a dark gray mixture of organic material and
sand in others and giving way to the underlying gray to light








10 Florida Agricultural Experiment Stations

gray sands in still others. A substratum of limestone or marl is
encountered at depths of 2 to 5 or more feet.
During the 1942-46 survey the revising author occasionally
encountered soils in the coastal areas with profiles so complex
that they cannot properly be placed in any one soil series. When
such soils were encountered in this survey, they were classified
as a complex of the two series they most nearly fitted, i.e.,
Sunniland-Charlotte complex.
In many low-lying coastal groves and in some low interior
groves the soil has been worked into beds or ridges on which
the trees are planted to improve drainage in the root zone. This
frequently causes a mixing of some subsoil with the surface
layer and considerably alters the surface soil texture and the
soil profile. Thus the profile of any particular soil in bedded
groves often may not conform well to the profile description
for that series, as given above, since these descriptions are
based on undisturbed virgin soils. Furthermore, where cal-
careous materials closely underlie the surface these are likely
to be worked into the surface layer in such quantities as to
alter greatly the reaction and chemical composition of the sur-
face layer.
This mixing and improved drainage may result in a soil
which, in actuality and for all practical purposes, is entirely
different from that under which it is classified. In fact, as a
result of fertilization, the addition of soil amendments, cover
crops and other cultural practices, the same might be said, to
a certain degree, for most Florida citrus soils after they have
been under cultivation for some time.
For a more complete description of the soils considered here,
as well as other soils not discussed in this publication, the reader
is referred to the maps and reports published by the Bureau of
Plant Industry, Soils and Agricultural Engineering and the Soil
Conservation Service of the United States Department of Agri-
culture and to Florida Agricultural Experiment Station Bulletin
334 and supplements.

COLLECTION AND PREPARATION OF SAMPLES
In the past fertilizer has been applied commonly over a cir-
cular area slightly larger than the actual spread of the tree;
however, many growers are now spreading the fertilizer in
older groves over the entire area by means of fertilizer-dis-
tributing machines. As a result, the soil is usually more acid








Chemical Studies on Soils from Florida Citrus Groves 11

in the area within the tree spread than in the middle of the
checks. From a preliminary study it was found that average
soil conditions, with respect to reaction, nutrient supply and
feeder roots, generally existed just beyond the periphery of
the tree. Therefore, the soil samples were taken immediately
outside the area of maximum leaf drip.
At least 12 borings were made in each grove for each sample,
one boring to a tree separating all well-defined soil horizons.
A stainless steel tube 11/2 inches in diameter was employed on
all soils of light texture (sands and mucks). On the heavier
soils (loams and clays) it was usually necessary to use a soil
auger. With the earlier portion of this study in most of the
light sandy soils in which the profile is quite simple, samples
were obtained at two different depths, the gray or dark surface
layer 5 to 7 inches thick being separated from the yellow,
reddish-yellow, grayish-white or light-gray subsoil. The sub-
soil samples for these were taken to an arbitrary depth of 18
inches except where there was a definite change in the soil
profile horizon within this depth. In the later survey, which
was confined to the coastal areas, more complex profiles were
encountered. Sampling was to whatever depth necessary to
secure samples from each layer within the principal root zone
of trees on the particular soil involved. Both the surface soil
and subsoil borings were composite separately in the field and
brought to the laboratory in quart glass jars where they were
air-dried, screened through a 2 mm aluminum sieve and thor-
oughly mixed.
A great variation in the weight per acre-six-inches was found
in the coastal area soils. In order to eliminate as much error
as possible in reporting certain soil constituents on a pounds-
per-acre basis, undisturbed volume weight samples were taken
from each soil horizon included in the later survey. These were
taken by means of a thin-walled steel cylinder having a volume
capacity of one two-millionth of an acre-six-inches.

METHODS OF ANALYSIS
The exchangeable bases (calcium, magnesium, potassium and
manganese) were extracted by leaching a 200-gram sample of
soil in a Buchner funnel with 800 ml. of 1 N ammonium acetate
adjusted to pH 7.0. After washing out the excess ammonium
acetate with 500 ml. of 80 percent neutral alcohol, the absorbed
ammonium was replaced by leaching with 500 ml. of 10 percent







12 Florida Agricultural Experiment Stations

solution of sodium chloride and determined by distillation in the
presence of calcium hydroxide. The ammonium acetate extract
containing the exchangeable bases was evaporated to dryness,
and the organic matter was destroyed by means of hydrogen
peroxide. After dehydrating the silica, the residue was dis-
solved in dilute HCI, filtered, and made up to a volume of 100 ml.
Calcium.-Calcium was precipitated as the oxalate in a 40
ml. aliquot, filtered, and washed with hot water, dissolved in 10
percent H2S04 and titrated with 0.05 N KMnO4. Prior to pre-
cipitation of calcium, iron and aluminum if percent were re-
moved with ammonium hydroxide.
Magnesium.-After the removal of calcium, magnesium was
precipitated as MgNH4PO4, filtered and washed with 10 percent
ammonium hydroxide. After drying, the precipitate was dis-
solved in 0.1 N H2S04 and the excess acid titrated with 0.1
N NaOH, using brom cresol green as the indicator (32).
In the analysis of the soils collected in the later (1942-46)
survey, magnesium was determined by the oxine method as
modified by Peech (50) for soil analysis.
Potassium.-An aliquot of 10 to 20 ml., depending on the
amount of potassium present, of the acid solution containing
the exchangeable bases was evaporated to dryness in the pres-
ence of a few drops of H2S04, and heated in an electric muffle
at dull redness to expel the ammonium salts and destroy the
last traces of organic matter. Potassium was then precipitated
as K2PtCl6, filtered and washed with 95 percent alcohol. The
precipitate was dissolved in hot water, and estimated colori-
mentrically (13) after developing the color by the addition of
an excess of KI and making up to a volume of 100 ml. For
analysis of the later survey samples the cobalt nitrite method
of Peech (50) was used.
Manganese.-A 20 ml. aliquot of the original solution was
evaporated to dryness in the presence of a few drops of H2S04
and ignited in an electric muffle to expell the chlorides and to
destroy the organic matter. Manganese was then extracted
with 20 ml. of 6 percent H2S04 and determined colorimentrically
(64) upon oxidation to permanganate by means of potassium
periodate. In the analysis of the later survey samples Peech's
adaptation (50) of this method to microanalysis was used.
Zinc and Copper.-Zinc and copper were determined by mak-
ing a separate extraction with 1 N NaCI solution. After pre-








Chemical Studies on Soils from Florida Citrus Groves 13

liminary work, sodium chloride was chosen as an extracting
solution for this purpose in preference to ammonium acetate
because of the greater solvent action of ammonium salts upon
the insoluble salts (phosphates and carbonates) of zinc and
copper. In view of the small amounts of zinc and copper present
in the readily exchangeable form in most Florida soils it was
thought that the use of 1 N NaCI solution as an extracting
reagent should give a better measure of the supply of available
zinc and copper.
The method finally adopted was as follows: A 100-gram
sample of soil was extracted with 200 ml. of 1 N NaCI for one
hour. The supernatant liquid was carefully poured off and
centrifuged. A 100 ml. aliquot of the clear extract was evapor-
ated to dryness after the addition of 2 ml. of 30 percent hydro-
gen peroxide to destroy the organic matter. The residue was
dissolved in 50 ml. of water containing 1.5 ml. cone. HC1. After
the addition of 5 ml. of 0.7 M ammonium citrate, the solution
was made slightly alkaline with ammonium hydroxide. Zinc
and copper were separated by repeated extraction with 0.01
precent solution of dithizone dissolved in CC4 according to the
procedure given by Sandell (55), which in turn is based on the
work of Fisher (23). Zinc was then separated from copper by
further extraction with 0.01 N HCI and determined colorimetric-
ally by means of dithizone. The colorimetric diethyldithiocar-
bamate method (21) was used in the determination of copper.
All reagents used in the determination of zinc and copper were
carefully purified. Distilled water was redistilled in Pyrex glass.
Total Nitrogen and Nitrate Nitrogen.-Total nitrogen was
determined by the Gunning-Hibbard method (2), while Harper's
(33) modification was used in the determination of the nitrate
nitrogen.
Organic Matter.-The organic matter content was determined
by loss on ignition, using the official method (2).
Acid-Soluble Phosphorus.-The amount of phosphorus dis-
solved in 0.002 N H2S04, pH 3.0, according to the method pro-
posed by Truog (62), was taken as a measure of the more
readily-soluble phosphorus in the soil. Due to the heterogeneous
nature of Florida light sandy soils, a larger sample of soil, 5
grams, was used instead of 2 grams as recommended by Truog
to 400 ml. of the extracting solution.
Water-Soluble Phosphorus.-The water-soluble phosphorus
was determined in 1:5 by weight soil-water extract.









14 Florida Agricultural Experiment Stations

Soil Reaction.-The pH value was measured by means of the
glass electrode using equal parts by volume of soil and water,
except with mucks where the volume of water was necessarily
2 to 3 times that of the soil.

RESULTS OF CHEMICAL ANALYSES
The amounts of calcium, magnesium, potassium, manganese,
zinc, copper, nitrate nitrogen, acid-soluble phosphorus and water-
soluble phosphorus are expressed in pounds per acre-six-inches
of moisture-free soil. In view of the vast amount of existing
data on the exchangeable bases on different soil groups that
have been expressed in milli-equivalents per 100 grams, the
following conversion factors are given to facilitate comparison
of the data presented here with those published in the liter-
ature.
Values given are for soils having a volume weight of 2,000,000
pounds per acre-six-inches, which was assumed for earlier
studies. Where the volume weight varies from this multiply

each value given by the relative volume weight. In Appendix Table
2
3 the relative volume weights (approximate) are given for the
soils studied in the later survey. A soil with a volume weight
of 2,000,000 pounds per acre-six-inches is arbitrarily assigned
a relative volume weight of 2.0. Thus a soil with a volume
weight of 1,000,000 pounds per acre-six-inches would have a
relative volume weight of 1.0 and a soil with a volume weight
of 2,200,000 pounds would have a relative volume weight of
2.2, etc.
One 401 pounds of calcium (Ca) per acre-six-inches of soil.
Milli- 243 pounds of magnesium (Mg) per acre-six-inches of soil.
equivalent 782 pounds of potassium (K) per acre-six-inches of soil.
is 549 pounds of manganese (Mn) per acre-six-inches of soil.
equivalent 654 pounds of zinc (Zn) per acre-six-inches of soil.
to 636 pounds of copper (Cu) per acre-six-inches of soil.
Total nitrogen and organic matter are expressed as percent-
ages of oven-dry soil. Approximate location, variety, age, and
general grove condition at time of sampling are recorded also.
To enable the reader to evaluate more critically variations
in composition, particularly with respect to such readily leach-
able constituents as nitrate nitrogen and potassium, the date
of the last fertilizer application prior to sampling, when obtain-
able, together with the date of sampling, is given in these tables
for each sample.







Chemical Studies on Soils from Florida Citrus Groves 15

The various samples within the same series have been ar-
ranged in Appendix Tables 1 and 3 in the increasing order of
their exchange capacities to show the variation in the composi-
tion among the different grove soils. Minimum, maximum and
average amounts of various constituents found in different soil
series are presented in Appendix Tables 2 and 4.

EXCHANGE CAPACITY AND DEGREE OF BASE
SATURATION
Exchange capacity may be defined as the capacity of a soil
to adsorb and retain in an exchangeable condition certain plant
nutrient elements-calcium, magnesium, potassium, ammonium-
nitrogen, manganese, zinc, copper-which are referred to as
exchangeable bases. The total quantity of the exchangeable
bases any soil can hold is a fixed quantity that can be varied
only with difficulty, and is determined by the amount of organic
matter or clay present in the soil. The organic matter, or more
correctly, the "humus," constitutes the main source of colloidal
material in many Florida citrus soils because of the small
amounts of clay present, and consequently the inorganic soil
colloids contribute very little to the exchange capacity. This
is substantiated by the ratios of the exchange capacity to the
percent of organic matter which remain quite constant despite
the great variations of the exchange capacity and the amount
of organic matter in these soils. The average value of the ratio,
exchange capacity/percent of organic matter, for all the soils
from the earlier survey shown in Appendix Table 1, with the
exception of six samples containing appreciable amounts of
clay, was found to be equal to 2.0. Hence a unit increase in
percentage of organic matter in the soil increases the exchange
capacity approximately by 2.0 milli-equivalents per 100 grams
of soil. This would give a value for the exchange capacity of
the soil organic matter approximately equal to 200 milli-equiva-
lents per 100 grams, which is in close agreement with the
values of exchange capacity of the organic matter in Coastal
Plain soils reported by Bartlett, Ruble and Thomas (6), as well
as in other soils reported by McGeorge (43), Mitchell (44) and
Olson and Bray (47). Some of the wide discrepancies noted in
the ratio, exchange capacity/percent organic matter, in samples
from the early and later surveys are due to the presence of
clay which would tend to make the ratios higher. In the later
survey (Appendix Table 3) a relatively larger number of soils







16 Florida Agricultural Experiment Stations

contained appreciable amounts of clay and this ratio was found
to average about 2.5 for the later survey samples.
It is interesting to note that five samples of marl-grove No.
84 sample No. 157, grove No. 87 samples No. 152 and 153, grove
No. 91 sample No. 146, and grove No. 92 sample No. 235-have
much lower exchange capacities than their textures would indi-
cate in the field. Three of the subsoil samples of marl, Nos.
153, 146, and 235, which had an apparent texture of a heavy
silt loam, showed an exchange capacity of only 3.0 6.6 and 4.1
m.e., respectively, per 100 grams. In most of the marl samples
the ratio, exchange capacity/percent organic matter, is below 2.0,
which would indicate that the exchange capacities of these soils
are also largely determined by their organic matter content.
However, in the case of marls containing appreciable propor-
tions of clay, the ratios are higher than 4.0.
One of the important factors affecting the exchange capacity
of the soil organic matter is its stage of decomposition, the
more humified portion of the organic matter having a higher
exchange capacity than the fraction that has not undergone
much decomposition. This is illustrated by the Davie series
(Appendix Table 3) which generally contained large amounts
of undecomposed organic matter in the surface layer. The
ratio, exchange capacity/organic matter, in the surface of these
soils averaged 1.0. In considering the individual components in
the soil that are responsible for base-exchange phenomena it
was thought that the presence of charcoal in some of the sam-
ples was the cause of some of the variations observed in the
ratios of exchange capacity to the percent of organic matter.
An examination of two samples of charcoal taken from Norfolk
fine sand showed an average exchange capacity of 117 milli-
equivalents per 100 grams of material, which is considerably
lower than average for the exchange capacity of soil organic
matter. Despite some of the above difficulties, the organic mat-
ter content affords a quick measure of the exchange capacity
in the light sandy soils, which in turn may be regarded as the
best single-value index to the relative potential fertility of the
majority of the soils planted to citrus in Florida.
The exchange capacity of the surface layer of the blackjack
oak land and the poorer grades of high pineland usually varies
from 1.5 to 2.0 m.e., while the better grades of high pineland
have an exchange capacity between 2.0 and 3.0 milli-equivalents
per 100 grams. Exchange capacity of the surface layer in high-








Chemical Studies on Soils from Florida Citrus Groves 17

hammock land is usually about 6.0, in low-hammock land about
10.0 or higher.
The surface layer of the palmetto and grassy flatwood soils
has an exchange capacity averaging around 5.5 and the prairie
soils, with the exception of the so-called mucks, about 4.5. The
muck soils, because of their high humate content, generally dis-
play a high exchange capacity. These soils are represented in
these studies by the Davie and associated series, Everglades
and Hialeah. The exchange capacity of the 26 surface samples
of Davie soils studied ranged from 11.88 to 100.80, with an
average of 39.46. Those of the associated series lay high within
this range. Three surface samples of Rockdale series soil from
Key Largo, high in organic matter, had an average exchange
capacity of 46.48 milli-equivalents per 100 grams.
It will be noted in Appendix Tables 1 and 3 that exchange
capacity of surface layers is generally considerably higher than
that of corresponding subsoils. This is because of the higher
organic matter content of the surface layers in well drained
sandy soils and most others. With imperfectly to poorly drained
sands and loams, having appreciable amounts of clay in the
subsoil, the exchange capacity of the subsoil occasionally is
higher than that of the surface layer because of the exchange
properties contributed by the clay. There are also several sub-
soils in this latter group in which the organic matter is higher
than in the corresponding surface layer, resulting in the higher
exchange capacity in the subsoil. The greater amounts of ex-
changeable bases are almost invariably present in the layer
having the higher exchange capacity. There are, however, some
exceptions to this because the total amount of exchangeable
bases such as calcium, magnesium, potassium and manganese
that a given soil may retain in a readily available form for
plant use is not wholly determined by the exchange capacity,
but the pH, or more correctly the percent of base saturation,
must also be taken into consideration.
The total sum of the exchangeable cations, excluding hydro-
gen, expressed as percent of the exchange capacity, is defined
as percent base saturation. A soil is 100 percent base-saturated
when the sum of the exchangeable calcium, magnesium, potas-
sium, manganese and other exchangeable bases is equal to the
exchange capacity. Such a soil should have a pH value of 7.0
unless free carbonates are present, in which case the -pH value
is above 7.0. At 50 percent base saturation half of the exchange









-,-



.5- ---- - --




S 10. -- .5- I -- 10




7.0 -- I
7..5- -- --- -- --- -- --- -- -- --- 7.- -- --- -- --- -- --- -- --- -- - ^ 0


6.56.5
__0 r.0 p
CURVE A 1937 data CURVE B 1942-46 data

from the 197 survey. from the 1942-46 survey.














Fig. .--Relationship between the pH value and percent of base saturation in both surface and subsoil samples


from citrus roves. Solid dot surface soil circle subsoil.
Fig.e.5-Re-ations hip betw the p vl an ectn nbth surfae and ssoil samples
f.0-rom 5.c---- ----srCe soil; circle,-subsoil.









of monobasic acid having pK 5.52, which is the aver- of monobasic acid having pK 5.41, which is the aver-
age apparent pK value found for all the soil samples age apparent pK value found for all the soil samples

from the 1937 survey, from the 1942-46 survey.

Fig. 1.-Relationship between the pH value and percent of base saturation in both surface and subsoil samples
from citrus groves. Solid dot, surface soil; circle, subsoil.








Chemical Studies on Soils from Florida Citrus Groves 19

capacity of a soil is utilized by bases like calcium, magnesium
and potassium and the other half is saturated with hydrogen,
which causes soil acidity.
The relationship between the degree of base saturation of the
various soil samples presented in Appendix Tables 1 and 3 and
their pH values is illustrated in Figure 1. Since by definition, base
saturation may be interpreted as the amount of base per unit
quantity of total potential soil acidity, it is evident that the rela-
tionship shown in Figure 1 is analogous to a titration curve
obtained by titrating a weak monobasic acid with a strong base
and the following well-known buffer equation may be applied,
(salt)
pH= pK+log .... (1)
(acid)
in which pK is the negative logarithm of the dissociation con-
stant of the acid. At the point of half-neutralization, the second
term of the equation becomes zero, and the pH value is numeri-
cally equal to the pK value of the acid. Bradfield (9) calculated
the "apparent pK values" for several colloidal clays from the
titration curves and showed that while such a treatment was
not strictly rigorous, the pK values calculated from the titration
curves were in close agreement with those obtained by other
methods. Although not all of the exchangeable hydrogen is
replaced at pH 7.0 (pH of the extracting solution used), we can
apply the above relationship to base-exchange data and evaluate
the average apparent value. Knowing the average apparent pK
value, it is possible to calculate the pH value, the total sum of the
exchangeable bases, or the exchange capacity from any two of the
three variables. Applying equation (1) to base-exchange data,
sum of exchangeable bases
pH = pK + log ... (2)
exchangeable H
or
(sum of exchangeable bases)
pH= pK + log ... (3)
(exchange capacity sum of exchangeable bases)
At 50 percent base saturation, the observed pH is equal to the
apparent pK value or the negative logarithm of the apparent
dissociation constant of the adsorbed hydrogen.
From data on exchange capacity, the sum of exchangeable
bases, and pH, apparent pK values were calculated for various
soil samples shown in Appendix Tables 1 and 3 by means of
equation (3). The average apparent pK value for the 1937








20 Florida Agricultural Experiment Stations

survey samples (Appendix Table 1) was found to be 5.52 and
that for the 1942-46 survey samples (Appendix Table 3) 5.41.
The values 5.52 and 5.41 were used in drawing the theoretical
curves in Figure 1, curves A and B respectively, showing the
relationship between the pH values and the percent base satura-
tion for each set of data. The slightly lower average apparent
pK value obtained from the 1942-46 data would indicate a
slightly higher degree of dissociation of the soil acids in the
soils examined in 1942-46 than those examined in 1937. It is
doubtful, however, if the values are significantly different be-
cause of the considerable departure from the curves of many
of the experimental points in both sets of data. This rather
wide distribution of experimental points probably results from
the difference in nature of base exchange complexes in different
soils and analytical difficulties encountered in the determination
of exchangeable bases. Presence of free fertilizer salts in the
soil and solubility of calcium, magnesium, and potassium salts
of organic acids in the extracting solution as pointed out
by Bray and DeTurk (10) would tend to give higher degrees
of base saturation than the pH values would indicate. The
majority of surface soil and subsoil samples shown in Figure 1,
curves A and B, having pH values above 5.5 showed more than
50 percent base saturation. The majority of the samples from
the 1937 survey, shown in Figure 1, curve A, having pH values
below 5.5 showed less than 50 percent base saturation, while
only approximately half of those from the 1942-46 survey, shown
in Figure 1, curve B, having pH values below 5.5 were less than
50 percent base saturated. It will be noted from both these
curves that the base saturation is increased from approximately
25 to approximately 75 percent by rasing the pH value of a
soil from 5.0 to 6.0. Regardless of the exchange capacity, a
given soil may be expected to contain approximately three times
as much exchangeable calcium at pH 6.0 as at pH 5.0.
In view of the low exchange capacity of many Florida grove
soils, it seems very desirable to maintain a high degree of base
saturation by replacing hydrogen with bases like calcium and
magnesium through applications of basic materials, but any
attempt to raise the degree of base saturation to exceed a cer-
tain pH value might render zinc and manganese unavailable,
thus inducing deficiencies of these elements (17, 19, 25). The
application of basic materials to maintain the pH value of the
soil between 5.5 to 6.0, which corresponds approximately to a







Chemical Studies on Soils from Florida Citrus Groves 21

base saturation of 50 to 75 percent, is being recommended for
best results. From the foregoing discussion it should be clear
that some caution should be exercised in estimating the lime
requirements of soils from pH values alone, without due con-
sideration to variation of exchange capacity in different soils.
For years many citrus growers in Florida were very reluctant
to make applications of any form of lime on grove soils, largely
due to over-liming injury (25) experienced prior to 1917. In
addition to this, the continuous use of acid-forming fertilizers
and the resultant increase of soil acidity below pH 5.0 prior to
about 1938 aggravated the depletion of the less abundant ele-
ments in soils-magnesium, manganese, zinc, and copper-to
the extent that these elements became the limiting factors in
production in many groves on light sandy soils. Typical ex-
amples of the analyses of light sandy grove soils very acid in
reaction are shown in Appendix Table 1 and are discussed later.
These conditions now have been largely corrected through a
more intelligent and practical pH control program.

EXHANGEABLE BASES
Calcium.-Since calcium is the predominating base in the
colloidal complex, the amount of exchangeable calcium found
in the various soils is closely correlated with the exchange
capacity at approximately the same pH values. For the same
reason, the exchangeable calcium was found to increase with
the increasing pH values in soils having the same exchange
capacity. The effect of the pH value or the degree of base
saturation on the actual amounts of calcium and other exchange-
able bases that may be found in a surface layer of Norfolk fine
sand with an average exchange capacity of 2.5 is clearly illus-
trated if the analysis of grove No. 28, sample No. 134, is com-
pared with that of grove No. 29, sample No. 182. As shown in
Appendix Tables 2 and 4, calcium (Ca) in the surface layer of
Norfolk soils varied from 149 to 1,668 pounds per acre, averaging
542 pounds.
In contrast to these light acid sands with low exchange ca-
pacity were the calcareous low hammock soils of the Parkwood,
Manatee, and Bradenton series. In most cases these soils have
a high exchange capacity and a high degree of base saturation.
(See Appendix Tables 1 and 3.) The amount of exchangeable
calcium in the surface layer of these low hammock soils varied
from 464 to 7,038 pounds per acre-six-inches, with an average







22 Florida Agricultural Experiment Stations

of 2,561 pounds. The manganese, zinc and iron in these soils
have a low degree of availability and deficiency symptoms
develop readily unless special corrective measures are taken.
Magnesium deficiency is also sometimes severe on these cal-
careous hammock soils, in spite of their usually relatively high
exchangeable magnesium content, because of excess calcium
which results in an unfavorably wide Ca:Mg ratio.
Appendix Tables 3 and 4 show that muck soils of the Davie,
Everglades, and Hialeah series, generally rather closely under-
lain with calcareous rock or marl, contained large amounts of
exchangeable calcium. In the surface layer of these mucks it
varied from 886 to 11,235 pounds per acre-six-inches, with an
average of 4,121 pounds. Although well supplied with calcium,
the percentage base saturation is usually comparatively low
because the exchange capacity is generally exceedingly high.
As a result, these soils are often quite acid.
The exchangeable calcium content of the several other soil
series included in the two surveys was quite variable, the aver-
age ranging from 291 to 7,811 pounds per acre-six-inches in the
surface layer. The great majority of these, however, were
within the lower limits of this range, usually averaging some-
what less than 1,600 pounds of exchangeable calcium in the
surface layer. These averaging over 1,600 pounds per acre-
six-inches were from the coastal areas and of relatively high
exchange capacity. These were most generally rather closely
underlain with some calcareous material such as marl, lime
rock or shell.
Magnesium.-Bahrt (3), Bahrt and Hughes (5), Bryan and
DeBusk (12) and Tait (61) have reported evidence of marked
responses of citrus to applications of dolomite and magnesium
sulfate. The chlorotic leaf pattern due to magnesium deficiency
as it occurs under field conditions in Florida has been described
by Fudge (27) and Camp (16). Fudge (28) made a study of
the chemical composition of fruit and foliage and has shown
that "bronzing" of citrus is definitely associated with magnesium
deficiency. Most light well-drained upland soils which had not
received an application of dolomite or soluble forms of mag-
nesium prior to the 1937 survey were found extremely deficient
in magnesium, containing less than 10 pounds of magnesium
per acre, regardless of the exchange capacity. Symptoms of
magnesium deficiency were invariably found in groves located
on such soils. Grove soils to which considerable amounts of








Chemical Studies on Soils from Florida Citrus Groves 23

bonemeal had been applied in the past contained somewhat
higher quantities of exchangeable magnesium. It should be
noted here that by 1937 magnesium had come into such general
use that a majority of the groves sampled had received at least
one application of dolomite or soluble forms of magnesium and
upon analysis showed considerable amounts of exchangeable
magnesium. Although the response from dolomite is slower
than from soluble magnesium, severely bronzed groves that had
received either form of magnesium in the fall of 1936 or the
spring of 1937 showed much less bronzing, in general, by the
spring of 1938. Soil samples taken from groves at the Citrus
Experiment Station, groves No. 12 and 16, in which the trees
showed a very marked response to the application of dolomite
and magnesium sulfate, are typical of the light sandy soils very
acid in reaction which had never received magnesium from any
of the common sources.
While magnesium applications had only come into recent use
at the time of the 1937 survey, most groves sampled in the
1942-46 survey had received a number of magnesium applica-
tions over a period of at least several years prior to sampling.
Various sources of magnesium were used and it was being ap-
plied as a separate material and in mixed fertilizers in rather
substantial amounts. A comparison of the magnesium content
of soil samples taken in the 1942-46 survey with that of samples
from the same soil series and of approximately equal exchange
capacity, taken in 1937, did not indicate that an appreciable
increase in the exchangeable magnesium content had occurred
in those particular soils as a result of this continued use of
magnesium. Because of the widely different soil types covered
in the major portions of the two surveys there were relatively
few truly comparable samples and little significance can be given
the comparison.
A more valid index of results of increased and continued use
of magnesium was the incidence of magnesium deficiency symp-
toms at the times of the two surveys. Bronzing was occasionally
observed on practically all soil types covered in 1942-46, but it
was not nearly so generally widespread as reported for trees
that had not received magnesium applications within a year or
so prior to sampling in 1937. The condition on calcareous low
hammock soils in 1942-46, however, was somewhat different.
The earlier study revealed that many of these calcareous soils
were inherently well supplied with magnesium. Trees growing








24 Florida Agricultural Experiment Stations

on these soils seldom showed symptoms of magnesium deficiency
at that time. Several years later, during the 1942-46 survey,
however, magnesium deficiency symptoms were not uncommon
on these calcareous soils. In some cases this was no doubt due
to gradual "cropping out" of the native magnesium in groves
where magnesium was not applied, or applied in insufficient
quantities as a neutral salt. Jamison (37) found the retention
of magnesium from neutral salts to be relatively poor in soils
at high pH values in the presence of unrestricted lime residues.
In other groves, on these calcareous soils, magnesium deficiency
symptoms had increased in recent years, even though magnesium
fertilizers had been rather consistently used for several ap-
plications, and the soils were found to contain rather large
quantities of exchangeable magnesium. However, the calcium
content of these soils was exceedingly high. Grove 114, sample
353, was an example of this condition. The surface soil here
contained 3,300 pounds of exchangeable calcium per acre and
110 pounds per acre of exchangeable magnesium; a ratio of
30:1. A Ca:Mg ratio of between about 8 or 10:1 has been
found desirable and necessary to prevent magnesium deficiency.
Fudge (29, 30) has shown that a high content in the soil of any
one base, in relation to other bases, will inhibit the absorption
and/or utilization within the plant of those bases present in
lesser amounts. This interrelation between bases, calcium and
magnesium here, would seem to account, at least in part, for
the increased bronzing found on this and some other similar
soils in spite of the fact that they contained relatively large
amounts of magnesium. Recently, increased bronzing noted on
calcareous soils can likely be attributed to the greater use during
the "war years" of magnesium sources low in quickly available
magnesium or low in reactivity on calcareous soils. Such ma-
terials as calcined magnesite and Brucite give unsatisfactory
results on soils with a reaction above about pH 6.0, but they
have been used frequently during the past few years as sub-
stitutes for the scarce magnesium sulfate (Emjeo) and sulfate
of potash-magnesia.
The acid soils, sometimes rather closely associated with these
calcareous series, generally contained much less and varying
amounts of both magnesium and calcium, depending upon the
exchange capacity and fertilizer practice. During the 1942-46
survey magnesium deficiency symptoms were observed no more
frequently on these acid soils than on the calcareous soils.








Chemical Studies on Soils from Florida Citrus Groves 25

The amount of magnesium (Mg) in the surface layer of Nor-
folk soils of the 1937 survey varied from 5 to 121 pounds per
acre, averaging 39 pounds. That in calcareous hammock soils
of the Parkwood series varied from 16 to 465 pounds, with an
average of 194 pounds. The average magnesium content found
for the different soil series in this earlier survey varied from
13 to 194 pounds per acre in the surface layer. At least partly
because of their usually higher exchange capacity, and perhaps
in some cases because of an actual increase in exchangeable
magnesium content, somewhat larger quantities of magnesium
were generally found in the several soil series in the 1942-46
survey than in 1937. This is exemplified by the samples from
the calcareous low hammock soils, now including the Parkwood,
Manatee and Bradenton series. The magnesium content in the
surface layers of these three series ranged from 9 to 940 pounds,
with an average of 277, 327 and 149 pounds per acre-six-inches,
respectively.
The average exchangeable magnesium content found in the
surface layer for the different soil series in the 1942-46 survey
varied from 14 to 358 pounds per acre.
It is now definitely established that the maintenance of an
adequate level of magnesium in the tree is essential to satis-
factory performance. On acid soils where sufficient dolomite
is applied for pH control at the recommended level (pH 5.5 to
6.0), a ratio of nitrogen to water-soluble magnesium (MgO) of
approximately 4:3 in the fertilizer has been found to accomplish
this satisfactorily. Where dolomite is not used for pH control
in acid soils this ratio should be 1:1, although in some such
cases it has been found advisable to use even more water-soluble
magnesium than this. On calcareous soils with a wide Ca:Mg
ratio it would not be feasible to narrow this ratio by applica-
tions of magnesium. The requirements of the tree can best be
met by rather frequent and relatively heavy applications of
water-soluble magnesium. On such soils a ratio of nitrogen
to water-soluble magnesium of at least 1:1 in the fertilizer is
recommended. Where magnesium deficiency symptoms persist
this ratio may profitably be increased to 2:3, or even 1:2, at
least until deficiency symptoms have disappeared.
Potassium.-Although considerable variation in amounts of
exchangeable potassium was found in soils having the same
exchange capacity, there is a general increase in amounts of
exchangeable potassium with increasing exchange capacity of








26 Florida Agricultural Experiment Stations

various soils included in the 1937 survey. It should be noted
also that the exchangeable potassium content of soils having
about the same exchange capacity usually was found to increase
with increasing pH values or degree of base saturation, even
where the same amounts of potash had been previously applied.
The effect of soil reaction (pH) or degree of base saturation
on the adsorption of potassium from salts such as muriate or
sulfate of potash can be readily explained on the basis of the
position of hydrogen, calcium and potassium in the lyotropic
series. Potassium replaces calcium more readily than it does
hydrogen and consequently the efficiency of the exchange com-
plex in adsorbing potassium applied in the form of salts of
strong acids is greatly increased at higher pH values because
of the greater amounts of exchangeable calcium present under
such conditions. Peech and Bradfield (52) have shown that the
amount of potassium adsorbed in exchangeable form by colloidal
clay was greatly increased by increasing the degree of calcium
saturation. The above considerations would further emphasize
the importance of maintaining proper soil reaction (pH) and
degree of base saturation in reducing losses by leaching, not
only of the common salts of potassium but of other fertilizer
materials generally applied in the form of salts of strong acids,
such as magnesium sulfate, manganese sulfate, copper sulfate,
zinc sulfate and ammonium sulfate. If comparison is made of
the small amounts of potassium found in acid sandy soils low in
exchange capacity, with an average annual application of potash
commonly used, it would seem that the loss of potassium through
leaching in such soils has been much greater than is usually
assumed. The amount of potassium (K) in the surface layer
of the Norfolk soils varied from 21 to 270 pounds per acre, aver-
aging 73 pounds. The average potassium content in the surface
layer of the different soil series of the 1937 study varied from
72 to 275 pounds per acre.
With the soils included in the 1942-46 study even wider vari-
ations in the amounts of exchangeable potassium were found
in soils having the same exchange capacity than were found
in the 1937 study. Moreover, only in an extremely general way
was the amount of exchangeable potassium found to increase
with the increasing exchange capacity of the various soils, and
there were many notable exceptions to this.
This would, at first, seem entirely inconsistent with the above
discussion based on the results of the earlier study. With a







Chemical Studies on Soils from Florida Citrus Groves 27

full consideration of the difference in the principal soil types
included in the two studies and other factors involved, this
seeming incongruity can be at least partly explained. Many
soils in the later survey contained relatively large amounts of
soluble calcium in addition to exchangeable calcium. As reported
by Peech and Bradfield (53), Kime (39), and Jamison (37),
potassium would be displaced by excessive amounts of calcium
in the soil solution. Thus, while potassium might be adsorbed
more readily by an exchange complex highly saturated with
calcium than by one saturated with hydrogen, the high concen-
tration of calcium ions in these soils would tend to displace this
exchangeable potassium and result in its ultimate leaching.
Consequently, the amount of exchangeable potassium found in
such soils, regardless of the exchange capacity, would be partly
dependent upon how soon after potash fertilization soil samples
were taken, and the amount of leaching by rainfall or irrigation
occurring during this interval. It is pertinent here to point out
that methods employed in these studies in extracting bases for
chemical analyses removed the water-soluble, as well as the ex-
changeable, fraction of these soil constituents. In reality, there-
fore, these data on exchangeable potassium contents, as well as
those for all other bases, are the sums of the exchangeable and
water-soluble fractions for the respective components.
Another influencing factor would be the age of the grove.
From the foregoing discussion it is apparent that most Florida
soils are inherently low in exchangeable potassium. A large
portion of that found upon analysis is from potash fertilizers.
Normally fertilizers are applied in proportion to tree size, older
groves receiving more than young groves. In some instances
the considerably higher exchangeable potassium content found
in one grove over another, on the same soil series with approxi-
mately the same exchange capacity, can reasonably be accounted
for in this manner. Also, some growers are inclined towards
heavier potash fertilization than others. Thus differences in
fertilizer practices can well account for rather wide differences
found in any fertilizer element in different groves of the same
age and on practically identical soils.
The average potassium content of all the different soil series
in the 1942-46 survey varied from 17 to 350 pounds per acre
in the surface layer, as shown in Appendix Table 4.
Manganese.-Skinner and Bahrt (57), Skinner, Bahrt and
Hughes (58), Bahrt and Hughes (4), and Roy (54) have re-







28 Florida Agricultural Experiment Stations

ported beneficial effects from applications of manganese to grove
soils in Florida. The leaf symptoms of manganese deficiency
were described by Camp and Reuther (19). Some of the con-
ditions under which the deficiency of manganese has been ag-
gravated in both acid and alkaline citrus soils in Florida were
discussed by Camp and Peech (17), who showed that manganese
deficiency in citrus occurred throughout the Florida growing
areas on both acid and alkaline soils. In the 1937 study most
soils examined were found to contain only small amounts of
exhangeable manganese, usually less than 3 pounds per acre
in the surface layer, regardless of exchange capacity; although
a few soils contained considerably more, bringing the average
for all surface soils studied to 3.39 pounds. From the limited
number of groves examined at that time it was impossible to
say whether such small amounts of manganese were adequate
to meet the requirements of citrus, but it should be pointed out
that distinct leaf symptoms of manganese deficiency were ob-
served in a large number of groves on soils containing around
3 pounds of exchangeable manganese in the susface layer.
It is interesting to note that the grove soil (sample No. 251,
grove No. 47) to which manganese sulfate had been applied
represents one of the few samples containing a larger amount
(17 pounds) of exchangeable manganese. There is no relation
between the exchangeable manganese content and the pH values
in the case of light sandy soils, although it should be noted that
two of the grove soils (groves No. 43 and 67) which had pre-
viously received large applications of lime contained only 0.3
and 1.2 pounds of manganese per acre, respectively. However,
the exchangeable manganese content of calcareous low hammock
soils was generally found to be closely correlated with the pH
value, regardless of previous manganese treatments. Soil sam-
ples taken from groves No. 84, 87, 91 and 92 are typical of the
so-called "marl spots" usually found in the cabbage-palmetto
hammock soils where the marl layer lies close to the surface or
has been mixed with the surface layer in ridging or mounding
the trees. Frenching due to zinc deficiency and pronounced
symptoms of manganese deficiency usually are associated with
these soils, or the combination of the two symptoms sometimes
locally referred to as "marl frenching."
Samples No. 142-4 and No. 145-6 were taken from two ad-
joining groves, Nos. 85 and 91, planted at the same time and
under the same management. The surface layer (sample No.








Chemical Studies on Soils from Florida Citrus Groves 29

142) of the profile in grove No. 85 consisted of 8 inches of dark
loamy fine sand, underlain by 10 inches of dingy brown fine
sand (sample No. 143) which changed abruptly into a very
plastic, slightly mottled yellowish clay (sample No. 144) about
6 inches in thickness resting upon marl and calcareous rock.
The trees in this grove were in excellent condition and some of
the finest groves in the low hammock areas were found on soils
having similar profiles. The surface layer (sample No. 145)
taken from adjoining grove No. 91, in which the trees showed
symptoms of both zinc and manganese dificiences, consisted of
6 inches of very dark to almost black sandy loam, underlain
immediately by a grayish to creamy white layer of marl (sample
No. 146). Although the surface layer in this type of porfile
as found in many other groves is strongly alkaline, about pH
8.0, the reaction of the surface layer in similar undisturbed pro-
files is somewhat acid, usually about pH 6.0. The higher pH
value of the surface layer in grove soils immediately underlain
by marl at a depth of 8 to 10 inches is undoubtedly due to mixing
of the marl layer in the process of ridging or mounding for the
trees. The reaction of the surface layer of grove soils having
a profile similar to that found in grove No. 85 is seldom above
pH 6.0 and in some cases may be as low as 4.88, as shown by
sample No. 272, grove No. 82, in which case the marl layer was
3 feet below the surface. The marl and calcareous rock in this
type of profile is usually 2 feet below the surface, underlying
a heavy plastic layer of clay, the lower part of which contains
some marl. It should be noted that although considerably more
manganese sulfate had been applied to the soil in grove No. 91
than in the adjoining grove No. 85, the surface layer (sample
No. 142) in grove No. 85 with a pH value of 5.46 showed upon
analysis about 12 times as much exchangeable manganese as
the surface layer (sample No. 145) in grove No. 91 having a
pH value of 7.86. Manganese is subject to oxidation and pre-
cipitation into non-exchangeable forms in soils having pH values
higher than about 6.5. That this "fixation" is quite rapid at
about pH 8.0 is borne out by the fact that the soil (sample
No. 157, grove No. 84) which had received an application of
manganese sulfate at the rate of 300 pounds per acre for three
consecutive years prior to sampling showed only 0.4 pound of
manganese in the exchangeable form at the time of sampling.
Since the manganese applications were made over a circular area
around the tree, the material was actually concentrated in this








30 Florida Agricultural Experiment Stations

area probably at the rate of 1,000 pounds per acre. While some
of this fixed manganese is no doubt at least slowly available,
it is evident that little or no increase in the exchangeable man-
ganese content of marl and other soils of high pH can be secured
through economically feasible applications of manganese salts.
A much larger portion of the soils in the later survey was
within the pH range where manganese is oxidized to a non-
exchangeable form. Less exchangeable manganese was found,
on the average, in these soils than those covered by the earlier
survey. A larger majority of the soils examined at the later
date contained less than 3 pounds of exchangeable manganese
per acre-six-inches in the surface layer, the average of all grove
surface soils being 2.57 pounds. Manganese deficiency symp-
toms, however, were not widespread in the groves of the later
survey. Many groves containing less than 3 pounds of ex-
changeable manganese per acre-six-inches showed no evidence
of manganese deficiency. Most of the deficiency symptoms ob-
served were on the marl spots.
In view of the comparatively infrequent occurrence of man-
ganese deficiency symptoms found in the later survey, even on
soils of high pH where the amounts of exchangeable manganese
were generally quite low, it is obvious that little correlation
existed with these soils between the exhangebale manganese
content, as determined here, and the incidence of manganese
deficiency symptoms. This low incidence of manganese deficiency
can be accounted for to a major degree by the greatly increased
use of manganese in recent years, with perhaps some slight
benefit in this respect through the increased use of certain other
elements, which resulted in a more vigorous tree better able to
secure small amounts of manganese present in the soil. It is
now customary to employ manganese sprays on trees on soils
having a reaction above about pH 6.5, with manganese some-
times also being used in the fertilizer. On the more acid soils
excellent results are obtained with manganese in the fertilizer
where pH control is practiced so as to maintain the soil reaction
between about pH 5.0 and 6.0, leaching of manganese not be-
coming appreciable until the soil reaction drops to about pH 4.8.
The inclusion of manganese in the fertilizer at the rate of about
0.5 to 1.0 percent, as MnO, applied once to three times a year
or/and in the spray at the rate of about 2 or 3 pounds of Mn SO4
(65%) per 100 gallons of water applied once a year, has served
to maintain the trees in good condition with respect to man-








Chemical Studies on Soils from Florida Citrus Groves 31

ganese. On alkaline soils, where the trees are more subject to
manganese deficiency, it is sometimes necessary to apply man-
ganese sprays more often for satisfactory results. From this
it seems evident that only relatively small applications of man-
ganese are necessary in order to avoid a deficiency if made fre-
quently enough and in the most advantageous manner for the
particular soil type concerned. It is pertinent to point out here
that, in addition to the better response secured, it is more eco-
nomical to resort to manganese spray on alkaline soils because
of the cost of the large amounts of manganese that would be
necessary on such soils.
Copper.-Although the use of copper in the correction of
exanthema of citrus, also known in Florida as diebackk" and
ammoniationn", dates back to 1910 (24), no attempt has been
made to correlate the occurrence of this physiological disorder
with the available copper content of the soil. Dieback and am-
moniation are often induced by excessive fertilization with nitro-
gen and both soil applications of bluestone and copper sprays
are used as corrective treatments.
As shown in Appendix Table 1, in the earlier survey, the
amount of copper found in the different soils regardless of the
exchange capacity was usually less than 0.4 pound per acre
in the surface layer where no copper had been recently applied.
Grove soils that had received an application of copper sulfate
during the few years prior to sampling invariably showed a
higher content of exchangeable copper. The soil in grove No.
17, sample No. 158, showing 4.0 pounds of copper per acre in
the surface layer had been treated with copper sulfate at the
rate of 2.5 pounds per tree one year before the samples were
taken. Copper sulfate was also applied to the soil in grove
No. 44 at the rate of 4 pounds per tree during the year before
the samples were taken and this is reflected in the higher copper
content, 2.6 pounds per acre-six-inches of the surface layer.
Peech (51) found that both copper and zinc were irreversibly
adsorbed, i.e., fixed in forms that are not exchangeable, in these
light sandy soils. Good evidence that copper is strongly fixed
into non-exchangeable forms by soil organic matter was pre-
sented by Jamison (35, 36). The trees in grove No. 62, which
showed at one time severe symptoms of dieback and ammoni-
ation, had received 3 applications of bluestone at the rate of 2
pounds per tree for each application during the 3-year period
prior to sampling but only 0.04 pound per acre of exchangeable








32 Florida Agricultural Experiment Stations

copper was found in the surface layer when the samples were
taken. A noteworthy observation in this case is that the trees
did not respond to the soil application of copper, which is rather
unusual since both soil applications and copper sprays usually
are equally effective on acid sandy soils. According to informa-
tion obtained from the grower, the trees in grove No. 22 had
never been treated with copper (sprays or soil applications),
yet when the samples were taken the trees in this grove were
in excellent condition, apparently free from the usual symptoms
of copper deficiency. The amount of copper found in the surface
soil was only 0.36 pound per acre, which would indicate that
under proper management and fertilization, especially with re-
gard to the use of nitrogen, the amount of copper necessary for
the proper growth of citrus is probably less than one pound per
acre, according to the method of analysis used here.
In the interval between the two surveys the use of copper
sulfate at the rate of about 0.5 to 1.5 percent, as CuO, in citrus
fertilizers had become so general that all but a few of the grove
soils included in the 1942-46 survey had received some copper
treatments. Those few groves which had not received some
copper in the fertilizer usually received some on the soil from
time to time as a separate application of bluestone.
Copper sprays for melanose and/or scab control also had be-
come the rule in most sections. Although the amount added
would not be great, doubtless some sprayed copper eventually
reaches the soil where it contributes to the exchangeable copper
content. Most soils examined in 1942-46 contained over 0.5
pound per acre of exchangeable copper in the surface layer,
which was somewhat higher than that in the soils studied in
1937. The soils examined in 1942-46 were generally of higher
exchange capacity than were those examined in 1937. One
would normally expect to find more exchangeable copper as well
as other exchangeable bases in soils having higher exchange
capacity. Thus it appears that the higher copper content found
in the soils of the later survey was not only due to the higher
exchange capacity of these soils but was also partly due to an
actual increase in their exchangeable copper content because of
the increased use of copper fertilizers and sprays. Symptoms
of copper deficiency were rarely encountered during this survey,
except in groves on the Davie series. The use of copper fertil-
izers on these soils generally had not been as consistent, nor in
as large amounts in comparison to the soil nitrogen content, as








Chemical Studies on Soils from Florida Citrus Groves 33

in most other soils surveyed. This becomes more evident after
an inspection of the data in Appendix Tables 3 and 4. Copper
sprays were also less frequently used in most groves on these
soils than in other sections. Ammoniation was found in several
of the groves surveyed on the Davie soils, and was more preva-
lent in groves about 12 years of age and over. It appeared to be
associated more with a low level of copper than with a high
nitrogen level, or the copper: nitrogen ratio. For example,
grove No. 195, sample No. 532, with 0.28 pound of exchangeable
copper and 1.06 percent total nitrogen, produced a high percent-
age of ammoniated fruit for at least two or three years prior
to sampling. These trees had been treated with a few applica-
tions of copper sulfate at the rate of about 0.75 pound per tree
per application several years before sampling, but had not re-
ceived any copper for at least two years before sampling. On
the other hand, several other groves on these soils, of which
grove No. 200, sample No. 542, was representative, with some-
what more copper (0.59 pound) and considerably more nitrogen
(2.50% total nitrogen), giving a slightly wider Cu: N ratio,
showed no evidence of copper deficiency. Occasionally groves
which do not respond as readily as could be desired to soil appli-
cations of copper are encountered on these soils. It has been
demonstrated (65) that one copper spray, using 3 pounds of
copper sulfate per 100 gallons of water, will entirely eliminate
a severe case of ammoniation in one season on these soils.
In view of the present widespread use of copper as a fungicide
in the control of melanose and scab in all areas, much of the
necessary copper is probably supplied in this form. Therefore,
no further attempt will be made to correlate the copper content
of the soils examined in these surveys with the occurrence of
symptoms of copper deficiency.
Zinc.-Camp (14, 15), Camp and Reuther (18, 19), and others
(20, 42, 45, 48, 60) have shown that zinc can be used effectively
in the control of "frenching" or "mottle-leaf" in citrus. During
the past decade many of the groves that had been severely
affected with frenching have been brought back into production
following a zinc spray. As shown by Camp and Reuther (19),
frenching of citrus occurs in Florida most commonly on acid
sandy soils (below pH 5.0) very low in exchange capacity, as
well as on calcareous or over-limed soils. They concluded that
zinc has been depleted in acid sandy soils as a result of leaching
and fixed into unavailable form in alkaline soils. However, no








34 Florida Agricultural Experiment Stations

studies were made of the amount of available zinc present in
the various soils.
It is evident from Appendix Table 1 that the majority of the
surface soils examined in 1937 contained 3 to 5 times as much
zinc as copper, although there was considerable variation in the
amounts of zinc ranging from 0.16 to 1.6 pounds per acre in
the surface layer in groves which had not received any soil ap-
plications of zinc materials. There was no significant difference
in the exchangeable zinc content among the various soil series
regardless of the exchange capacity or the organic matter con-
tent. However, the poorer grades of well-drained upland soils
having exchange capacities below 2.0 and which had been main-
tained very acid in reaction, below pH 5.0, over a period of time
almost invariably contained less than 0.5 pound of zinc per
acre in the surface layer. Typical chemical analyses of such
grove soils are illustrated by samples taken from groves No.
1, 2, 3, 26 and 30, in which trees showed symptoms of zinc de-
ficiency at time of sampling. It has been reported previously
by Floyd (25) and Camp and Reuther (19) that frenching may
be readily induced by over-liming, and in view of the fact that
trees growing on calcareous soils are frequently affected with
frenching, it would appear that zinc is fixed and rendered un-
available in soils by lime above a certain pH value. These
observations are further substantiated by the investigations of
Lott (41), who showed that the toxicity of large applications
of zinc oxide to the soils could be inhibited by liming to raise
the pH values to 6.2. It is interesting to note that soils (groves
No. 43, 56 and 67) which had been heavily limed at one time
contained less than 0.2 pound of zinc per acre in the surface
layer. Trees in these groves showed pronounced symptoms of
zinc deficiency at time of sampling. It will be noted also that
11 out of 15 surface samples of Parkwood soils, in the 1937
survey, with a reaction of pH 6.0 to 8.3, with only 2 exceptions,
showed less than 0.2 pound of zinc per acre. On the other hand,
4 of the remaining Parkwood soils, in this same survey, having
pH values below 6.0 in the surface layer contained a higher
amount of zinc, ranging from 0.3 to 2.2 pounds per acre. It has
been stated already that trees on these soils were commonly
affected by zinc and manganese deficiencies. Apparently zinc
is fixed at pH values above 6.0, whereas the oxidation and pre-
cipitation of manganese begins above pH 6.5 and proceeds very
rapidly in soils at pH 8.0.








Chemical Studies on Soils from Florida Citrus Groves 35

The trees in groves No. 21, 29 and 32 were treated with zinc
sulfate at the rate of 50 pounds per acre one year prior to
sampling. It will be noted that the surface samples from these
groves contained the highest amounts of zinc found in the survey,
ranging from about 2 to 6 pounds per acre. Since an application
of 50 pounds of zinc sulfate (36 percent metallic zinc) is equiva-
lent to 18 pounds of metallic zinc, the above recovery after one
year is as good as might be expected on this type of soil. More-
over, Peech (51) has shown that zinc is irreversibly adsorbed
in light sandy soils. Jamison (36) points out that the soil or-
ganic matter is involved in the mechanism of this reversion
of zinc to non-exchangeable forms. Jones, Gall and Barnette
(38) have reported studies on the fixation of zinc in several
different Florida soils. Their results, however, showing re-
coveries of zinc applied as zinc sulfate to a Norfolk sand at
different periods of time during the year following the applica-
tion, as well as the amounts of exchangeable zinc found in the
untreated soils, are much higher than those presented here.
It would appear, therefore, that the ineffectiveness of soil ap-
plications of zinc sulfate as compared to the zinc spray method
of treatment in the correction of frenching on light sandy soils
as reported by Camp (14, 15) and Camp and Reuther (18, 19)
could well be attributed to fixation of zinc into non-exchange-
able forms. In their experiments on the correction of frenching
in citrus, they found that, in the case of light sandy soils, soil
applications even at the rates of 5 to 10 pounds per tree were
not so effective as the zinc spray method of treatment. The
failure of soil applications of zinc sulfate to correct frenching
may be due, in some cases at least, to the inability of the trees
to utilize zinc added to the soil because of the poor root system
of the affected trees, an explanation that has been advanced
by Chandler (20).
Zinc deficiency symptoms were not found to be widespread on
a majority of the soils covered in the later survey. On soils
with a reaction below pH 6.0 zinc deficiency symptoms were
rarely encountered. On the more alkaline soils this deficiency
became somewhat more prevalent and was not uncommon on
marl spots, which have a pH of about 7.5 or higher. This rela-
tively low incidence of zinc deficiency doubtless was primarily
due to the greatly increased use of zinc sprays within the past
10 years. While not nearly so universally used as zinc sprays,
zinc fertilizer applications have increased considerably in the







36 Florida Agricultural Experiment Stations

past few years on a few soil series and probably accounted for
improvement in some instances. The Davie, Leon and Norfolk
series were the coastal soils most generally receiving soil treat-
ments of zinc.
As in the earlier survey, there was little or no correlation
between the exchangeable zinc content of various soils and their
exchange capacity or organic matter content. There did appear
to be, however, some relationship between the soil pH and its
exchangeable zinc content in the later survey samples. The
average zinc content of the surface layer of the 30 soils with
pH below 5.00, in the 1942-46 study, was 3.27 pounds, that of
the 42 soils with pH 5.00 to 5.99 was 1.41 pounds, while the 55
soils with pH 6.00 or higher averaged only 0.31 pound per acre.
The high zinc content of the most acid group may be accounted
for by the low degree of zinc fixation accurring in these soils,
plus the fact that included in this group were a number of soils
on which zinc fertilizers had been used within a year or so
prior to sampling. Many of these groves also had received
zinc sprays. As with copper, some of the zinc applied as a spray
reaches the soil eventually and would add further to the ex-
changeable zinc content. A few of the soils in the other two
pH groups had received zinc fertilizers, but such treatments
are not common on these less acid soils. Zinc sprays have been
resorted to almost entirely, especially on soils above pH 6.0.
It was pointed out earlier that zinc is fixed in a non-exchange-
able form in soils above about pH 6.0; which accounts for the
low zinc content in this pH group. Few of the groves on soils
with a pH range from 5.0 to 6.0 had received zinc fertilizers,
but most of them had received zinc sprays. Although only small
amounts of zinc were added, to these soils directly in the fertil-
izer, or indirectly through the spray, it was sufficient to increase
the amount of exchangeable zinc, especially because of the rela-
tively low capacity of the soils in this pH range to fix zinc.
The recent increased use of zinc, in both spray and fertilizer,
apparently is reflected in the exchangeable zinc content of some
grove soils. A comparison of the zinc content of soils taken
in the earlier survey (Appendix Table 1) with that of soils from
the same series and of approximately the same pH taken in the
later survey (Appendix Table 3) indicates that an increase in
zinc has occurred at least in these particular soils. The average
exchangeable zinc content of the soils surveyed in 1937 was 0.72
pound per acre in the surface layer. The average for the surface
soils in the 1942-46 survey was 1.37 pounds.








Chemical Studies on Soils from Florida Citrus Groves 37

In the later study considerable variation in the zinc content
of soils, even within the same series, was found, depending to
a great extent upon the recency of a zinc treatment. For
example, in the Davie series the zinc content ranged from 0.06
to 21.0 pounds per acre in the surface layer. With this series,
where zinc was above 4 pounds, a supplemental application of
zinc sulfate at the rate of approximately 0.7 pound per tree
had been given a short time prior to sampling.
From the above considerations it is obvious that any recent
soil applications of zinc made prior to the date of sampling would
be reflected in the analysis and would tend to obscure any rela-
tionship between the amounts of zinc found in the grove soils
examined and the occurrence of frenching. In some instances
it was difficult to ascertain whether zinc had been used in the
spray program or included in the mixed fertilizer; hence, any
further correlation of the zinc content of the soils examined with
the occurrence of frenching will be dispensed with in this pub-
lication. It is now established, however, that frenching is caused
by a deficiency of available zinc in the soil and that the range
between what may be considered an adequate amount and a
deficiency is probably very narrow.

ORGANIC MATTER
The organic matter content was determined by loss on ignition.
In loams containing appreciable amounts of clay this method
is not quite so satisfactory because the loss on ignition included
water of hydration of the clay minerals.
Since the majority of the sandy soils of Florida contain frag-
ments of charcoal, especially at lower depths, the more tedious
dry and wet combustion methods are likely to give high results,
especially if the conventional factor, 1.724, is used in converting
the organic carbon to organic matter. The samples that were
known to contain free carbonates were treated with ammonium
carbonate after the ignition in order to correct for the loss in
weight due to decomposition of carbonates.
Results of determinations of the organic matter content are
shown in Appendix Tables 1 and 3, expressed as percent of the
oven-dry soil. For purposes of comparison, 1 percent of organic
matter, or any soil constituent, is equivalent to 20,000 pounds
per acre-six-inches where the weight of an acre-six-inches of
soil is 2,000,000 pounds, which was assumed for the 1937 data.
With the 1942-46 data, in which the actual volume weight of








38 Florida Agricultural Experiment Stations

the soil was used, percent can be converted to pounds per acre-
six-inches by using the following equation:
Percent x relative volume weight of soil (shown in Appendix
Table 3) x 1,000,000 --= pounds per acre-six-inches
It will be noted that there is considerable variation in the or-
ganic matter content among the various soil groups, or within
the same soil series in both surveys. The organic matter con-
tent of the Norfolk soils varied from 0.8 to 2.6 percent for the
surface soils and from 0.4 to 1.4 percent for the subsoils, al-
though the amounts of organic matter found in the subsoils
were more or less constant (about 0.6 percent) in the majority
of the Norfolk soils examined. Organic matter content of the
Eustis soils varied in the same manner. Blanton soils contained
somewhat higher amounts of organic matter than Norfolk soils.
In general, the organic matter content of poorly drained soils
was higher than that of the well drained group. One surface
sample of Parkwood loam, grove No. 91, contained as much as
10 percent organic matter. The surface layer of the muck soils,
including the Davie, Everglades and Hialeah series, were, with
but few exceptions, much higher in organic matter than any of
the other series examined, averaging around 50 percent. The
organic matter in the subsoils of these mucks was much lower,
averaging slightly less than 3 percent.
The relationship between exchange capacity and organic mat-
ter content has been discussed already. Exchange capacity, as
well as total amount of exchangeable bases, was found directly
related to organic matter content in the majority of soils exam-
ined. The higher exchange capacity and consequently the larger
amounts of exchangeable bases of the surface soils as compared
with the corresponding subsoils, found in a large majority of
soils examined, can be attributed also to the differences in the
relative amounts of organic matter. In a few cases (see Ap-
pendix Tables 1 and 3) in Parkwood, Manatee, Bradenton,
Portsmouth, Bladen, Felda, Charlotte, Arzell, Delray, Leon, Im-
mokalee and Sunniland series some of the subsoils had a higher
exchange capacity and larger amounts of exchangeable bases
than the corresponding surface layers. With all these, except
the last three, this was caused by more clay in the subsoil than
in the surface. In the last three series the higher exchange
capacity, and consequently the higher exchangeable base con-
tent, in the subsoil resulted from organic matter present as
precipitated humates in stained or "hard-pan" layers. In addi-








Chemical Studies on Soils from Florida Citrus Groves 39

tion to its base-exchange properties and moisture-holding ca-
pacity, the organic matter upon decomposition liberates nitrogen,
calcium, magnesium, potassium, phosphorus and other plant
nutrient elements. The carbonic acid formed resulting from
the decomposition of the organic matter increases the hydrolysis
of the exchangeable bases and helps to bring into solution the
more insoluble minerals and compounds in the soil.

TOTAL NITROGEN, NITRATE NITROGEN, AND
THE C:N RATIO
As might be expected, total nitrogen content was found
closely related to the amount of organic matter, as shown in
Appendix Tables 1 and 3. It has been reported by many investi-
gators that the carbon:nitrogen ratio of the soil organic matter
is about 10 within narrow limits, depending upon climatic con-
ditions and soil type. However, Anderson and Byers (1) reported
a wide divergence among the C:N ratios of different great soil
groups. They also showed considerable variation of the C:N
ratio with depth. Hosking (34), working with Australian soils,
found that the C:N ratio is a specific property of a soil under
natural and undisturbed conditions, but that upon cultivation
there is a greater loss of carbon than nitrogen, which results
in a narrowing of the ratio. The C:N ratio, therefore, may be
considered an important characteristic of the soil organic matter
and is more or less indicative of its stage of decomposition.
In calculating the C:N ratios given in Appendix Tables 1 and
3 the organic carbon was obtained by dividing the organic mat-
ter content as determined by loss on ignition by the conventional
factor 1.724. While this procedure may not give the absolute
values for the C:N ratios, as obtained by the direct determina-
tion of the organic carbon, because of the uncertainty of the
conversion factor, the C:N ratios calculated in this manner can
be used as an index to the relative decomposition of the organic
matter in the various soils examined. It will be noted that there
is a wide variation in the C:N ratios among the various samples
shown in Appendix Tables 1 and 3. Within a given series,
however, the ratios usually remain fairly constant for the surface
samples of the 1937 survey. They were much less constant for
the surface samples of the 1942-46 survey, probably because
of greater variation in intensity of cultivation practiced in the
coastal areas in different groves on the same soil series. The
subsoil samples from both surveys generally showed higher and








40 Florida Agricultural Experiment Stations

more variable ratios. This apparently was due to fragments
of charcoal which were usually found at lower depths in many
of the light sandy soils and to undecomposed organic matter
in some coastal subsoils examined. As shown in Appendix
Tables 2 and 4, the average C:N ratio in the surface samples
ranged from 11 to 103. Leighty and Shorey (40) also have re-
ported a wide variation in the C:N ratio in a number of Coastal
Plain soils, even within the same series. The 10 Norfolk pro-
files taken from Florida, South Carolina and Virginia gave vari-
able C:N ratios ranging from 7 to 26 in the surface layer. The
soils reported on here, especially those of the Orlando and
Gainesville series of the 1937 survey and the Blanton and Rock-
dale series of the 1942-46 survey, seem to have a higher C:N
ratio than is usually found in the cultivated soils of the great
soil groups. The high C:N ratio of the Rockdale series is due
to the presence of large quantities of undecomposed organic
matter which had accumulated in the limerock "pot-holes"
where Key lime trees were planted and maintained under a non-
cultivation system. Whether the high C:N ratio of the other
three series may be interpreted as denoting the presence of a
large quantity of decomposable organic matter or other highly
carbonaceous material such as charcoal, remains to be investi-
gated. There is no consistent relationship between the C:N ratio
of the organic matter and its exchange capacity (per unit
weight) as given by the ratio, exchange capacity/percent or-
ganic matter.
As shown in Appendix Tables 1 and 3, there is no apparent
relationship between amount of organic matter, C:N ratio and
nitrate nitrogen content. For example, the surface layer of the
Parkwood soil in grove No. 91, with a C:N ratio of 12, contained
10.6 percent organic matter and 375 pounds of nitrate nitrogen
per acre, while the Parkwood surface soil in grove No. 89, with
a C:N ratio of 13, contained 3.80 percent organic matter and 7
pounds of nitrate nitrogen. The surface layer of the Davie soil
in grove No. 192, with a C:N ratio of 89, contained 10.72 percent
organic matter and 130 pounds of nitrate nitrogen. Grove No.
206, on this same soil, had a C:N ratio of 15, with 48.25 percent
organic matter and 114 pounds of nitrate nitrogen in the surface
layer, while grove No. 202, also on Davie soil, with practically
the same C:N ratio and organic matter percentage, contained
but 46 pounds of nitrate nitrogen per acre-six-inches. The
amount of nitrate nitrogen is subject to wide seasonal fluctua-








Chemical Studies on Soils from Florida Citrus Groves 41

tions because it is so readily affected by leaching following
heavy rains and by fertilization. It is obvious that a single de-
termination of the nitrate nitrogen, as in this case, does not
justify drawing any conclusions.
The decomposition of the plant material and the formation
of ammonia and nitrate nitrogen following, for example, the
plowing under of summer cover crops is also intimately asso-
ciated with the C:N ratio of the plant material incorporated
with the soil. Bell (7) has made a study of the comparative
rate of decomposition of several leguminous and non-leguminous
cover crops in Norfolk sand with and without the addition of
inorganic fertilizers in which he found a striking difference in
the rate of nitrate accumulation from the various organic ma-
terials. It is generally accepted that if the C:N ratio is low,
as in the case of leguminous crops, ammonia and nitrate nitrogen
will appear in the soil in excess of that required by the soil
microorganisms for body synthesis. On the other hand, if the
C:N ratio of the plant material is high the oxidation of the
carbon will likely take place at the expense of the available
nitrogen so that there may be actually a temporary depression
in the amount of ammoniacal and nitrate nitrogen in the soil
following the incorporation of plant material low in nitrogen.
In either case the C:N ratio of the material will be narrowed
and will tend to approach the C:N ratio of the soil, the value of
which is more or less constant for a given set of climatic and
soil conditions.
It is obvious, therefore, that the decomposition of the plant
material and its subsequent effect on the accumulation of the
organic matter and nitrates in the soil is influenced by the C:N
ratio of the plant material. Upon decomposition only a small
portion of the total plant material added goes to increase the
organic matter or the humus content of the soil. In addition
to climatic factors favoring rapid decomposition of the soil or-
ganic matter in Florida soils, the practice of intensive fertil-
ization with complete fertilizers has, no doubt, expedited the
rate of depletion of the soil organic matter. Despite the diffi-
culties attendant in building up the amount of organic matter,
particularly in well-drained light sandy soils under Florida con-
ditions, the practice of growing and turning under of summer
cover crops should at least help to maintain the initial content
of organic matter as shown by Stokes, Barnette, Jones and Jef-
feries (59). In their studies of the effects of summer cover crops








42 Florida Agricultural Experiment Stations

(Crotalaria striata, velvet beans, beggarweed and cowpeas) on
the soil organic matter as well as on tree growth and fruit yield,
they found that the organic matter content in the clean-culture
plot decreased by one-third during the seven-year period of the
experiment. There was also a definite correlation between the
quantity of cover crops grown and growth and fruit yield of
the trees.

ACID-SOLUBLE AND WATER-SOLUBLE PHOSPHORUS
In contrast to the determination of exchangeable bases,
methods that have been proposed for determining the readily
available phosphorus in soils are much more empirical. Al-
though phosphate is adsorbed to some extent through anionic
exchange by some inorganic soil colloids (56), it is unlikely
that much of the available soil phosphorus exists in this form
in the light sandy soils of Florida. Various acids-nitric, hydro-
chloric, sulfuric, acetic, citric, carbonic-of different strengths
as well as alkaline salts, such as potassium carbonate, have been
used to determine the nature and the availability of phosphorus
in soils. Although a considerable amount of information has
been gained regarding the availability of different forms of
phosphorus in soils, the results obtained by such empirical
methods are only relative and their use in predicting the need
for phosphate fertilization must necessarily be established upon
proper correlation with plant response. Among the methods
proposed for the determination of the readily available phos-
phorus in soils, the 0.002 N H2S04 method developed by Truog
(62) has been widely used in this country. Davis and Scarseth
(22) found a high degree of correlation between the amount of
readily soluble phosphorus as obtained by Truog's method and
the crop yields in a number of Alabama soils, including 22 rep-
resentative Norfolk soils. Bryan (11) has reported that there
is an accumulation of available phosphorus in old citrus groves
on light sandy soils of Florida as measured by the method of
Truog. The amount of water-soluble phosphorus dissolved in
1:5 aqueous extracts was also higher in the surface soil in old
seedling and budded groves than in young trees.
Truog's method slightly modified was used to determine that
amount of readily soluble phosphorus in both studies. Because
of the heterogeneous nature of Florida soils, it is difficult to
weigh out a representative 2-gram sample of soil as recommended
by Truog. For this reason, a larger sample, 5 grams, was ex-








Chemical Studies on Soils from Florida Citrus Groves 43

tracted with 400 ml. of the extracting solution. Upon careful
checking it was found that this deviation did not affect results
except in cases where the amount of phosphorus was unusually
high (over 2,500 pounds P per acre).
The amount of readily soluble phosphorus as determined by
this method is designated as "acid-soluble" P in Appendix Tables
1, 2, 3 and 4. From Appendix Tables 2 and 4 it will be noted
that the acid-soluble phosphorus of the surface samples varied
between wide limits, ranging from 3 to 1,840 pounds per acre.

TABLE 1.-VARIATION IN AMOUNT OF ACID-SOLUBLE PHOSPHORUS IN THE
SURFACE SAMPLES OF 204 CITRUS GROVE SOILS.

Phosphorus
Lbs. per Acre- 0- 50- 100- 200- 300- 400- 600- 800- 1000- 1500-
six-inches 49 99 199 299 399 599 799 999 1499 2000

Number of groves 8 7 14 17 13 17 9 1 1
(1937 Study)

Number of Groves 39 16 16 14 7 10 3 2 4 0
(1942-46 Study)

Total (1937 and 47 23 30 31 20 27 12 3 10 1
1942-46 Studies)

Percent of
Total Groves 23.0 11.3 14.7 15.2 9.8 13.2 5.9 1.5 4.9 0.5


As shown in Table 1, in which the groves have been arbi-
trarily grouped into 10 classes in accordance with the amount
of phosphorus found in the surface soil, the acid-soluble phos-
phorus content was less than 100 pounds in 70 grove soils, be-
tween 100 and 600 pounds in 108, and over 600 pounds in 26
grove soils. The amount of acid-soluble phosphorus was usually
much higher in the surface-soil samples than in the correspond-
ing subsoil samples, but there is generally an increase in the
amount of phosphorus in the subsoils with the increasing amount
of phosphorus in the corresponding surface soils. It is interest-
ing to note that in three different soils-Portsmouth, Parkwood
and Bladen (groves No. 74, 81 and 93)-collected in the vicinity
of Bradenton, the amount of phosphorus was found to increase
with depth, the average of the acid-soluble phosphorus in the







44 Florida Agricultural Experiment Stations

subsoil of the three groves being approximately a ton more
per acre than in the surface soil. The high phosphorus content
of these soils was found to be associated with a highly mottled
bluish clay in the subsoil containing a large amount of acid-
soluble and water-soluble phosphorus. Apparently a highly
phosphatic material had been deposited with the clay and had
now become more or less distributed throughout the profile.
With the exception of the above soils, and a few others with
variations of much less magnitude, the amount of acid-soluble
phosphorus was higher in the surface layer than in the corre-
sponding subsoil, which would indicate that the readily soluble
phosphorus content has been increased by fertilization.
It should be noted here that while the Truog method has been
used successfully in evaluating the amount of readily soluble phos-
phorus in acid soils it is not adapted to calcareous soils because
of the poor buffer capacity of the extracting solution. Lower
results are obtained with calcareous soils, somewhat in propor-
tion to the amount of excess calcium carbonate present. This
should be borne in mind in the interpretation of the data pre-
sented for soils containing excess amounts of calcium carbonate,
particularly those containing a large excess. Such soils are 100
percent base-saturated and have a pH value above 7.0. By
reference to Appendix Tables 1 and 3 it is found that a large
portion of either the surface or subsoil samples from the Park-
wood, Manatee and Davie series, as well as a few surface or sub-
soil samples from several other series fall in this category. In
Figure 2 the amounts of acid-soluble phosphorus in the surface
samples were plotted against the age of the respective groves
for all groves in both surveys. In a general way the acid-soluble
phosphorus content of the surface samples is related to the age
of the grove, regardless of soil type. However, several notable
exceptions are apparent in Figure 2, which would indicate that
the rate of accumulation of phosphorus in different grove soils
is not constant but probably varies with soil type and other
factors. That the capacity of different soils to fix phosphate
varies greatly, depending upon chemical composition (calcium,
iron and aluminum content) and soil reaction is well known.
The exact nature of the phosphorus, soluble in 0.002 N H2SO4
according to the Truog method, that has apparently accumulated
in some grove soils, as well as the soil conditions under which
phosphorus is "fixed" into comparatively readily soluble form,
are not known at present. It has been shown by Gaarder (31),








Chemical Studies on Soils from Florida Citrus Groves 45

2000

1800 -- --

1600 1

1400 -i -


S'
1200

1000
o ,





400

o 0 !_
200 o


0 5 10 15 20 25 30 35 40 45 50 55 60
Age Years
Fig. 2.-Relation of amounts of acid-soluble phosphorus found in sur-
face soils to ages of citrus groves. Circle, 1937 data; solid dot, 1942-46
data.

Benne, Perkins and King (8) and others that the reversion of
phosphate to tri-calcium phosphate proceeds in soils only at
high pH values, starting at about pH 5.5 but not reaching a
maximum until pH 7.5 is approached. Since about half the
grove soils examined had been maintained probably below pH
5.5 and comparatively few above pH 7.0, it is reasonable to
assume that reversion of soluble phosphate applied as super-
phosphate would have occurred in appreciable amounts only in
relatively few soils. Hence, it is not likely that the acid-soluble
phosphate represents the reverted tri-calcium phosphate. This
apparent accumulation of phosphorus in readily soluble form
in some of the grove soils can hardly be attributed to fixation
by iron or aluminum, inasmuch as iron and aluminum phosphates
are only slightly soluble in 0.002 N H2S04 (63). In fact, re-
peated tests showed only traces of soluble iron in the 0.002
N H2S04 extracts. Some of the preliminary studies of factors
affecting the accumulation of readily soluble phosphorus in
grove soils have shown that different sources of phosphate have
different residual effects as determined by Truog's method.








46 Florida Agricultural Experiment Stations

The water-soluble phosphorus was determined in 1:5 soil-water
extracts. It was necessary to flocculate some suspensions of
subsoils containing appreciable amounts of clay with sodium
sulfate in order to obtain clear aqueous extracts. The amount
of water-soluble phosphorus varied from about 0 to 42 pounds
per acre in the surface layer. As shown in Figure 3, there is
an apparent relationship between the water-soluble and the acid-
soluble phosphorus in the surface samples. On the other hand,
the amount of water-soluble phosphorus bears no relation to
the amount of acid-soluble phosphorus in the case of subsoils.
It should be noted, however, that the amount of water-soluble
phosphorus in the subsoil is usually higher in groves showing
a high content of acid-soluble and water-soluble phosphorus in
the surface layer. It is obvious, therefore, that there is gen-
erally a downward movement of water-soluble phosphorus in
soils showing a large amount of acid-soluble phosphorus in the
surface layer. The amounts of phosphorus dissolved in 1:5

45


40


35


30


250
25 __ __o o _


3 20 --------_---
Io 0.0 0- 0----
0o o

o oo
)0 P 0 0




O0*
5 *60 0 0 0

0 e 0




0 200 400 600 800 000 1200 400 1600 800 2000
Acid Soluble Phosphorus Pounds Per Acre
Fig. 3.-Relation of water-soluble phosphorus to acid-soluble phos-
phorus in the surface samples of citrus grove soils. Circle, 1937 data;
"solid dot, 1942-46 data.








Chemical Studies on Soils from Florida Citrus Groves 47

soil-water extracts are not related to the pH values of the soils,
except in the case of calcareous samples which frequently showed
only traces or small amounts of water-soluble phosphorus.
It is evident from the foregoing discussion that the supply
of readily soluble phosphorus in the grove soils of Florida has
been appreciably increased in some cases by use of phosphatic
fertilizers. While the exact nature and the availability of the
phosphorus as measured by the 0.002 N H2S04 method has not
been established, the large amounts of water-soluble phosphorus
found in some of the groves showing a high acid-soluble phos-
phorus content would indicate that it should be readily available.
Reasons for wide differences in the amounts of acid-soluble
phosphorus found among the different grove soils are obscure
but probably involve a number of factors such as soil type,
soil reaction and chemical composition of the soil, as well as
the sources of phosphorus used.
It should be mentioned here that the various experimental
plots at the Citrus Experiment Station now containing widely
different amounts of acid-soluble phosphorus in the soil throw
little or no light as to the significance of the varying amounts
of phosphorus found in these sandy soils. In fact, with the ex-
ception of a limited amount of such information for the Davie
series, there are as yet no systematic field plot experimental
data showing the response of citrus to varying amounts of phos-
phorus for any Florida soils. The Davie series soils are inher-
ently low in phosphorus, as evidenced by virgin soil samples
Nos. 198V, 207V, and 208V in Appendix Table 3. Results from
experimental field plots with Lue Gim Gong oranges on these
soils (26, 46) indicate that trees which received no phosphate
fertilizer after they were five years old yielded less fruit and
fruit of poorer quality than did phosphate-fertilized trees. This
difference in quantity and quality became evident when the trees
were about 10 years old and had been under experimental treat-
ment for four or five years. It continued until the experiment
was terminated after about 11 years. Available records on the
grove where these plots were located show that prior to the
establishment of the experiment all trees received 1/ to 21/
pounds per tree semi-annually of an N-P-K fertilizer containing
8 to 12 percent P205. After about seven or eight years under
the no-phosphate treatment the trees were, on the average,
slightly smaller and apparently of less vigor than the phosphate-
fertilized trees. Samples Nos. 536 and 544 (Appendix Table 3)







48 Florida Agricultural Experiment Stations

were taken from no-phosphate treatment plots at that time.
They contained 25 and 26 pounds, respectively, of acid-soluble
phosphorus per acre-six-inches. Sample No. 530 was from plots
which had received 6 percent P205 fertilizer since the inception
of the experiment. It contained 50 pounds of acid-soluble phos-
phorus. The significance of these differences in acid-soluble
phosphate contents seem doubtful, however. There was equally
as much or more difference in the acid-soluble phosphorus con-
tent of samples from nearby commercial grove of the same age
and on the same soil which had received regular commercial
applications of phosphate for eight years or more. The date
of the last fertilizer application before sampling and date of
sampling was practically the same on the experimental plots
and these particular commercial groves. Some of the commer-
cial grove soils contained considerably more acid-soluble phos-
phorus than that from the 6 percent P205 treated plots. Others
contained little more than the no-phosphate treatment plots.
Yield records were not available for these commercial groves,
but the tree condition was in all cases equal to that of the phos-
phate-treated experimental plots. Thus it is apparent that
there was little or no correlation between the acid-soluble phos-
phorus of the soil, as determined here, and tree condition on
these soils.
Symptoms of phosphorus deficiency on citrus in the field have
never been reported elsewhere in Florida, and there are no re-
ports of phosphorus toxicity. Until symptoms of phosphorus
deficiency and toxicity, if the latter condition actually exists,
are identified on a wide variety of soils and the specific effects
of phosphorus on the growth of the tree, as well as on yield
and fruit quality, are more thoroughly understood for citrus,
it will be impossible to attach much practical significance to the
wide differences in the amounts of acid-soluble phosphorus found
in different grove soils.

COMPARISON OF SOME GROVE SOILS WITH
ADJOINING VIRGIN SOILS
Seven samples of virgin soils adjoining groves on the same
soil series were taken for comparison. These are designated
as 2V, 19V, 54V, 72V, 173V, 198V and 208V and the correspond-
ing groves as 2, 19, 54, 72, 174, 205 and 203, in Appendix Tables
1 and 3. The first five of these are on light sandy soils and it
will be noted, with the exception of grove No. 2, that both or-








Chemical Studies on Soils from Florida Citrus Groves 49

ganic matter content and exchange capacity are higher in grove
soils than in corresponding virgin soils. Although the total
nitrogen content had been increased in these four grove soils,
the values of the C:N ratios had decreased as a result of fertil-
ization and cultivation in all except grove No. 174 (corresponding
virgin soil No. 173V). This latter was a young grove in which
cultural practices would have had little time to influence the
C:N ratio. The amounts of calcium, potassium, acid-soluble
phosphorus, water-soluble phosphorus and nitrate nitrogen also
had been increased by fertilization. Groves No. 205 and 203
(corresponding virgin soils No. 198V and 208V) were on the
Davie soil series. The general fertility of both of these appar-
ently had been increased by fertilization. However, the great
variations found within a short distance in these soils in their
inherent high organic matter and calcium contents would tend
to obscure any effects cultivation and fertilization may have
had on these constituents, as well as on those influenced by or-
ganic matter, such as total nitrogen and the C:N ratio. The
significance of the difference in the chemical composition ob-
served between these grove soils and the adjoining virgin soils
cannot be ascertained from the limited number of comparisons
available for this study.
Samples were taken for study from several other virgin soils
and a few previously farmed areas being considered for citrus,
but not adjoining citrus plantings on the same soil series. These
virgin soils are listed in Appendix Table 3 as 117V, 123V, 125V,
149V, 150V, 156V, 176V, 207V and 217V. The previously farmed
soils are listed in this table as 104F, 126F, 172F and 177F. In
general, all these were found to be considerably lower in fertility
than the average grove soil of the same series and texture.

VOLUME WEIGHTS OF SOIL
The volume weight of a soil is dependent on its texture, struc-
ture and composition. Coarse-textured soils such as sands have
little or no structure. The pore space in such soils is low.
They are composed of relatively dense materials. As a result
of all these factors, sands have a high volume weight (apparent
specific gravity). On the other extreme are the organic soils
with a high degree of porosity and with a great portion of their
volume composed of humus of low density. These organic soils,
or mucks, are generally of low volume weight. Intermediate
between these extremes are the clays, calcareous clays or marls,







50 Florida Agricultural Experiment Stations

and loams. The clays and marls are less dense than the sands
and more dense than humus. Organic matter, clay and marl
each tend to increase soil porosity. The volume weight of a
loam soil consisting of a mixture of any or all of these materials
with sand obviously will be governed somewhat by the propor-
tions in which these various components are present.
Citrus grove soils of roughly the same texture, structure and
composition have approximately the same volume weight. The
great majority of the soils included in the 1937 survey were
light sands relatively low in organic matter. Only a few con-
tained appreciable amounts of clay or marl. Consequently, a
volume weight of 2,000,000 pounds per acre-six-inches was as-
sumed for all the soils of the earlier survey. As a rule, the
soils included in the 1942-46 survey contained more organic
matter than those of the 1937 survey and many of them also
contained appreciable amounts of clay or marl, but there was
much variation in texture, structure and composition. This
resulted in considerable variation in volume weights of the dif-
ferent soils examined in the later survey. Somewhat more
variation was found in the surface layer of these soils than in
the corresponding subsoil. As shown in Appendix Table 3, the
relative volume weight in the surface layer ranged from 0.6
to 2.3. In the subsoil the range was from 1.4 to 2.4. Because
of the higher organic matter content and more porous nature
of the surface soil, its volume weight was usually less than that
of the corresponding subsoil. This difference was particularly
pronounced in the Davie and associated muck series. The sur-
face layer of these muck soils generally contains large amounts
of organic matter and is quite porous. On the other hand, their
subsoils are composed of sands or mixtures of marl and sand
with little organic matter. As a result, they are relatively more
dense. In a few instances the volume weight of a sandy surface
soil was greater than the corresponding subsoil because of large
amounts of organic matter, clay or marl in the subsoil.

GENERAL DISCUSSION
It has been shown previously that the base-exchange property
of the majority of Florida grove soils is largely due to organic
matter, with clay also playing an important role in this respect
in some soils, particularly in a number of the coastal soils. Hence
the problem of building up and maintaining the organic matter
in soils should be of primary importance in any program of soil








Chemical Studies on Soils from Florida Citrus Groves 51

management, especially in the light sandy soils. Not only is
the exchange capacity the best single-value index to the fer-
tility of the various soil types planted to citrus but it determines,
within narrow limits, the total amount of exchangeable bases
(calcium, magnesium, potassium) that can be maintained in the
soil with a given fertilizer practice and management. This
is well illustrated by the samples of Norfolk sand taken from
groves No. 1, 2, 3 and 4 (Appendix Table 1), which represent
the poorest grade Norfolk soils and are typical of what is locally
called blackjack-oak land. One of the surface samples, No. 292,
grove No. 2, showing 64 percent base saturation and a pH value
of 6.2, actually contains smaller amounts of exchangeable bases
than the better grade of Norfolk soils having an exchange ca-
pacity about 3.0 and much lower pH values. In many instances,
abrupt variations in the exchange capacity were observed within
the same soil type in the same grove. Such variations were
often markedly reflected in the tree conditions, especially where
no adjustment had been made in the fertilizer practice. The
effect of variation of exchange capacity upon the content of
exchangeable bases is clearly depicted if we compare the analyses
of samples taken from two adjoining groves, Nos. 5 and 53, at
approximately the same pH values. The general appearance
of the trees in grove No. 5 was very poor, while those in the
adjacent grove No. 53 were in excellent condition and appar-
ently free from any of the common deficiency symptoms, al-
though both groves had received identical fertilizer treatment
under the same management. It would be futile to attempt to
maintain the same amounts of calcium, potassium and mag-
nesium, for example, in both of these grove soils because simple
calculations show that the sum total of the exchangeable bases
in the surface sample No. 200, grove No. 53, exceeds the total
exchange capacity of the surface sample No. 198, grove No. 5,
by 1.9 milli-equivalents per 100 grams. In order to minimize
losses through leaching following heavy rainfalls in soils having
such low exchange capacities (from 1.5 to 2.0 m.e.) it would
seem necessary to make smaller but more frequent applications
of fertilizers. The effect of exchange capacity on general grove
condition, as shown in Appendix Table 1, was rather accentuated
in the 1937 study by a number of limiting factors such as mag-
nesium, manganese, zinc and copper deficiencies, which of course
were especially pronounced in groves on soils having low ex-
change capacities and low pH values (below 5.0). With the in-








52 Florida Agricultural Experiment Stations

creasing use of these elements and the maintenance of a higher
degree of base saturation by a careful control of the pH value
of the soil, differences in grove conditions due to variations in
exchange capacity now have been largely overcome.
Importance of the maintenance of organic matter content in
light sandy soils is further emphasized if we compare exchange
capacities and amounts of exchangeable bases in surface sam-
ples with those found in corresponding subsoil samples. During
the course of sampling it was observed that most of the fine
fibrous roots were present in the surface layer, usually from
4 to 6 inches in depth, and that only a few fibrous roots pene-
trated into the yellow, gray or grayish-white subsoil imme-
diately below the surface layer. This limited distribution of
the fibrous roots, probably due to great differences in chemical
composition, between the surface layer and the subsoil, is a
serious drawback during periods of drouth when the trees suffer
severely from lack of moisture.
In addition to exchange capacity, variation in depth to clay
beds in the case of light sandy soils has a very decided influence
on grove condition, other factors remaining constant. It was
observed in several instances on such soils that in places where
the clay was within 3 to 4 feet of the surface the trees appeared
to be in much better condition than where the depth to clay
was more than 7 feet. With sandy soils the beneficial effect
of the clay at a depth of 3 to 4 feet is probably due to better
moisture conditions and the greater efficiency of the fertilizer
materials applied, since losses by leaching may be expected to
be somewhat reduced under.such conditions.
Problems associated with poorly drained soils along the East
and West Coasts are somewhat more variable. Groves on low
hammock soils in which the marl layer lies either near the sur-
face or has been mixed with the surface layer in the process
of mounding or ridging the trees cause considerable trouble be-
cause of manganese and zinc deficiencies. The lack of proper water
control and effective irrigation, salt injury arising from salt
water overflow and high salt content of irrigation waters
(artesian wells) present some of the other important problems
in the East and West Coast areas.
In several instances during the course of the discussion of the
chemical data on the various soils, reference has been made to
the general grove condition as well as to the specific deficiency
symptoms. It should be noted in this connection that no con-








Chemical Studies on Soils from Florida Citrus Groves 53

sistent relationship between the chemical composition of a soil
and the general condition of the grove on that soil, as shown
in Appendix Tables 1 and 3, seems to exist. Many of the better
groves were on what would appear to be the poorer soils from
a fertility standpoint, while the converse is equally apparent in
many other cases. Other factors, soil moisture for example, no
doubt frequently control the general grove condition more, at
least temporarily, than does the chemical composition of the
soil. Thus the influence of soil fertility may be masked at times.
Since the information compiled thus far is obviously inadequate
for the purpose of establishing correlations between the chemical
composition of the soil and the general grove condition, no con-
clusions are being drawn regarding the optimum amounts or
ratios of the various nutrient elements in the soil necessary for
the best growth of citrus in the most economical manner. Fur-
ther and more specific investigations along these lines in regard
to some of the elements are now being carried on.

SUMMARY
A chemical study was made of 204 soils collected from groves
in the important citrus areas of the state and covering a wide
range of grove conditions on representative soil types. The
chemical analyses included the determination of exchange ca-
pacity; percent base saturation; exchangeable calcium, mag-
nesium, potassium, manganese, zinc and copper; acid (0.002
N H2SO4)-soluble phosphorus; water-soluble phosphorus; total
nitrogen; nitrate nitrogen; organic matter (loss on ignition);
and soil reaction (pH). The chemical data presented show the
variations in composition among the different soil samples
within the same series as well as minimum, maximum and aver-
age amounts of the various constituents found in the different
soil series. Results of analyses and some of the inferences drawn
are briefly summarized below.
The well-drained upland soils of the state that are most ex-
tensively planted to citrus, commonly known as a blackjack lands
and high pinelands, including Norfolk, Blanton, Eustis and Lake-
wood series, have a very low exchange capacity, usually between
2 and 3 milli-equivalents per 100 grams. The base-exchange
property of these soils is largely determined by their organic
matter content, as shown by the constancy of the ratios, ex-
change capacity/percent organic matter. In these soils the ex-
change capacity increased approximately by 2.0 m.e. per unit








54 Florida Agricultural Experiment Stations

increase in the percentage of organic matter. The high hammock
soils-which include Norfolk fine sand, hammock phase; Eustis
fine sand, dark colored phase; Orlando fine sand and Gainesville
fine sand-are somewhat better citrus soils than the blackjack
and high pineland soils. The exchange capacity of these high
hammock soils was found to vary between about 3.5 and 8.5
m.e., with the ratio, exchange capacity/percent organic matter,
ranging from about 1.5 to 2.2.
The base exchange property is also influenced by the clay frac-
tion of the soil. In some of the soils examined, particularly those
in coastal groves, clay was present in appreciable amounts. With
such soils the exchange capacity and the ratio, exchange ca-
pacity/percent organic matter, is somewhat higher than in the
average upland soil. The low hammock soils, including the
Parkwood, Manatee and Bradenton series, were probably the
first and are still among the soils most extensively planted to
citrus in the coastal areas. The exchange capacity of these
was found to range from 3.80 to 24.04 m.e., with the ratio of
exchange capacity/percent organic matter ranging from 1.38
to 4.90. Leon has been one of the most commonly planted coastal
flatwoods soils. The Leon soils examined in these studies varied
in exchange capacity from 4.58 to 7.44 m.e. Clay was not
present in these and the ratio, exchange capacity/percent or-
ganic matter, varied from 1.40 to 2.06. The Felda series is
fairly representative of the coastal prairie soils planted to citrus.
The exchange capacity of the Felda soils studied ranged from
2.74 to 10.30 m.e., with the ratio, exchange capacity/percent
organic matter, varying from 0.27 to 3.13. Within recent years
the organic prairie soils, or so-called mucks, have been increas-
ingly utilized for citrus. These are represented here by the
Davie series soils which, because of their high content of humus,
had high exchange capacities; varying from 11.88 to 100.80 m.e.
Large quantities of undecomposed organic matter still present
in these muck soils, however, result in low exchange capacity/
percent organic matter ratios, ranging from 0.26 to 2.51.
It was found that the exchange capacity affords the best
single-value index to the relative potential fertility of the various
soils planted to citrus. The average value for the exchange
capacity of the different soil series varied from 1.67 to 77.85
milli-equivalents per 100 grams in the surface layer.
A fair general relationship was found between the degree of
base saturation and the pH values in both surface and subsoil








Chemical Studies on Soils from Florida Citrus Groves 55

samples showing a wide variation in exchange capacity. The
average apparent pK value was calculated separately for the
earlier and for the later survey samples from their respective
data on the exchange capacity, total sum of exchangeable bases,
and the pH of all the samples examined in each survey. It was
found to be 5.52 for the 1937 samples and 5.41 for the 1942-46
samples. Each is closely equal to the pH value at 50 percent
base saturation. In order to provide an adequate supply of
exchangeable bases in soils of low exchange capacity, and to
minimize losses by leaching of fertilizer materials applied in
the form of salts of strong acids, it is highly desirable to main-
tain a high degree of base saturation by the addition of some
form of basic material. The use of sufficient basic materials to
maintain the soil reaction between pH 5.5 and 6.0, which cor-
responds approximately to a base saturation of 50 to 75 percent,
is being recommended for best results.
During the past decade the use of dolomite for pH control
and as a source of calcium and magnesium has increased greatly.
The 1942-46 survey did not include a sufficient number of sam-
ples from the same acid soil series covered by the 1937 survey,
and on which dolomite applications are normally made, to permit
sweeping conclusions as to the influence dolomite has on the soil
reaction and the calcium and magnesium contents of such soils.
The few data of this nature available, however, indicate that
soils thus treated are now generally less acid and contain more
calcium and magnesium than at the time of the earlier survey.
While in a general way there was an increase in the amount
of exchangeable potassium with increasing exchange capacity
of the various soils there were notable exceptions to this. Excess
amounts of unattached calcium ions in some soils, amount of
rainfall between potash fertilization and date of sampling, and
amount of potash fertilizer applied may each, or in various com-
binations, be factors influencing the exchangeable potassium
content more, in some cases, than does the exchange capacity.
Most of the light sandy soils examined in 1937 were found
very deficient in magnesium, manganese, zinc and copper. The
small amounts of these elements found may be attributed to the
low levels existing in the virgin soils and to the fact that up
to that time they had been added in insufficient amounts to
meet grove needs. These deficiencies had been further aggra-
vated by the excessive losses due to'leaching as a result of con-








56 Florida Agricultural Experiment Stations

tinuous use of acid-forming fertilizers without the correction
of the resultant increase of soil acidity. As a result, these ele-
ments had become limiting factors in production in many groves.
Magnesium applications had only recently come into fairly
general use at the time of the 1937 survey. In many instances
the amount of exchangeable magnesium found in 1937 was
less than 10 pounds per acre where this element had not been
applied. Approximately half the soils surveyed then contained
less than 50 pounds of exchangeable magnesium per acre. Mag-
nesium deficiency symptoms were common. By 1942-46 mag-
nesium fertilizers and dolomite were in common use. Magnesium
deficiency symptoms were not widespread, except on soils with
an unfavorably wide Ca :Mg ratio or where a slow-acting water-
insoluble material had been used as the principal source of mag-
nesium. Widely different soil types were covered in the major
portions of the earlier and later surveys. Thus, a comparison
of the magnesium contents found in the soils at these two differ-
ent dates is of little significance. However, comparatively few
of the groves surveyed in 1942-46 contained less than 50 pounds
of exchangeable magnesium per acre-six-inches and approxi-
mately half of them contained over 100 pounds in the surface
layer.
The average manganese content of the surface soils in the
1937 survey was 3.39 pounds per acre-six-inches. The 1942-46
survey, made for the most part on different soil series, showed
an average of 2.57 pounds of exchangeable manganese per acre
in the surface soil. The lesser amount of manganese found by
the later survey probably can be accounted for by the differences
in soil types covered by the two surveys, since manganese fer-
tilizers and sprays had been in common use for several years
at the later date. Because of the rather general use of man-
ganese at regular intervals, either in the fertilizer or as a spray,
manganese deficiency symptoms were confined mostly to soils
where some unfavorable circumstances prevailed, such as ex-
ceedingly high soil reaction or water damage to the root system.
The average zinc content of the surface soils studied in 1937
was 0.72 pound per acre-six-inches and the copper was 0.43
pound. In the interval between the two surveys zinc and copper
sprays had become the rule. Copper had became a constituent
in most fertilizers and zinc also was being included in some.
The increased use of these elements appeared to be reflected by
a considerable reduction in their deficiency symptoms, and,








Chemical Studies on Soils from Florida Citrus Groves 57

with some soils, by more or less evidence of an increase in the
amounts of these elements in the soil. The surface layer of the
soils in the 1942-46 study contained an average of 1.51 pounds
of exchangeable zinc and 0.72 pound of exchangeable copper
per acre-six-inches.
The use of phosphatic fertilizers has, in some cases, definitely
increased the amount of readily soluble phosphorus in the soil.
Most grove soils were found to contain from 100 to 600 pounds
of readily soluble phosphorus as determined by Truog's method.
In a general way, the acid-soluble phosphorus content in surface
soil samples was related to the age of the grove. The amount
of water-soluble phosphorus was found to increase with the in-
creasing amount of acid-soluble phosphorus in the surface layer.
Although the exact nature and the availability of the accumu-
lated phosphorus have not been established, the large amounts
of water-soluble phosphorus found in some of the grove soils
showing a high content of acid-soluble phosphorus would indicate
that it should be readily available.
A wide variation in C:N ratio was found to exist among the
different series with average values varying from 11 to 103 in
the surface soils. Within any given series of the well-drained,
sandy, upland soils the ratios were usually fairly constant.
There was considerably more variation in the ratios within a
given series for most of the coastal soils. Whether the high
C:N ratio of many of these soils may be interpreted to denote
the presence of a large quantity of decomposable organic matter
or other highly carbonaceous material such as charcoal which
was often found, especially at lower depths, remains to be in-
vestigated.

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58 Florida Agricultural Experiment Stations

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178-188. 1938.









Chemical Studies on Soils from Florida Citrus Groves 59

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60 Florida Agricultural Experiment Stations

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State Hort. Soc. 50: 29-37. 1937.








Chemical Studies on Soils from Florida Citrus Groves 61

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State Hort. Soc. 49: 9-14. 1936.

62. TRUOG, E. The determination of the readily available phosphorus of
soils. Jour. Amer. Soc. Agron. 22: 974-882. 1930.
63. TRUOG, E. Present status and future of soil testing and soil analysis.
Proc. Soil Sci. Soc. Amer. 2: 181-183. 1937.

64. WILLARD, H. H., and L. GREATHOUSE. Colorimetric determination of
manganese by oxidation with periodate. Jour. Amer. Chem. Soc.
39: 2366-2377. 1917.

65. YOUNG, T. W. Citrus investigations in the coastal regions-production
studies. Fla. Agr. Exp. Sta. Ann. Rept. 1945: 183-184. 1945.










APPENDIX

TABLE 1.-CHEMICAL ANALYSES OF THE MAJOR CITRUS GROVE SOILS OF FLORIDA (1937 SURVEY).

SPounds per Acre-Six-Inches of Soil2
Exchangeable Bases P F i




Norfolk 1 290 0-5 6.06 53.0 1.39 246 21 29 0.3 0.16 0.10 88 7 5 0.023 0.91 1.53 23 Babson Seedy 18 P 4-19-37
s. 291 5-18 5.30 13.0 0.74 28 2 16 0.0 0.24 0.10 22 3 0 0.010 0.53 1.40 31 Park Gft.
Norfolk 2 292 0-5 6.25 64.0 1.41 290 37 21 0.0 0.16 0.12 160 7 2 0.022 0.93 1.52 2 Frost- Valencia 15 P ........ 4-19-37
s. 293 5-18 4.96 13.5 0.80 28 5 13 0.0 0.16 0.06 32 2 0 0.008 0.63 1.27 46 proof 0.
Norfolk 2V 294 0-5 5.21 11.5 1.51 56 5 11 0.4 0.32 0.06 0 1 4 0.021 1.32 1.15 36 Frost- Virgin ........ 4-19-37
s. 295 5-18 5.31 10.8 0.60 13 5 10 0.1 0.16 0.06 0 0 0.008 0.60 1.00 44 proof ISoil
Norfolk 3 296 0- 5.86 44.8 1.45 193 30 33 1.2 0.16 0.12 307 8 3 0.025 0.92 1.58 21 Frost- Valencia 18? P 4-19-37
s. 297 6-18 4.96 16.7 0.81 40 3 17 0.3 0.24 0.10 32 3 0 0.011 0.59 1.37 31 proof O.
Norfolk 4 300 0-6 4.96 32.8 1.54 150 19 40 1.5 1.10 0.30 227 9 20.028 0.99 1.56 21 Daven- Pineapple 13 P 2- ?-37 4-21-37
s. 301 6-18 4.38 12.2 0.94 28 3 25 0.0 0.32 0.30 32 1 0 0.012 0.65 1.45 31 port O.
Norfolk 5 198 0-6 6.25 86.0 1.54 484 10 62 0.5 0.16 0.30 229 6 100.020 0.89 1.73 26 Apopka Pineapple 18 P 1-?-37 3-2-37
f. a. 199 6-1 5.10 16.5 1.02 48 2 33 0.3 0.16 0.06 58 2 0.008 0.56 1.82 41 0.
Norfolk 6 306 0-6 6.25 77.5 1.64 415 43 40 1.6 0.56 0.92 227 9 2 0.028 0.98 1.68 20 Wav- Valencia 20 E 4-22-37
s. 307 6-1 5.01 15.2 0.77 28 6 17 0.1 0.24 0.92 48 7 2 0.007 0.42 1.88 35 early 0.
Norfolk 7 140 0-5 5.39 51.5 1.67 300 14 41 2.3 0.96 0.14 176 9 6 0.024 0.93 1.80 22 Lake Valencia 14 P 2-5-37
f. s. 141 5-18 5.09 15.5 0.76 32 4 18 0.5 0.32 0.12 32 2 20.008 0.53 1.43 38 Wales O.
Norfolk 8 298 0-6 5.25 42.5 1.70 216 29 50 1.0 4.4 0.30 480 14 4 0.028 1.06 1.60 22 Daven- Seedy 23 P 2- -37 4-21-37
s. 299 6-18 4.29 13.5 0.96 33 27 0.1 0.32 0.14 80 6 2 0.010 0.57 1.69 33 port Gft.
Norfolk 9 124 0-6 6.30 92.5 1.71 532 0 35 2.1 0.64 0.20 272 10 1110.032 1.25 1.37 23 Avon Pineapple 20? G .2-4-37
f. s. 125 6-1 4.85 15.0 0.80 32 6 11 0.5 0.32 0.16 32 2 0 0.009 0.63 1.27 41 Park O.

1 The following abbreviations are used in soil type: s.-sand, f.-fine, v.-very.
Based on 2 million pounds per acre-six-inches of soil.
The following abbreviations are used in evaluating the general grove condition: (P)-poor, (F)-fair, (G)-good, (E)-excellent.
N.D.-not determined.








TABLE 1.-CHEMICAL ANALYSES OF THE MAJOR CITRUS GROVE SOILS OF FLORIDA (1937 SURvEY)-Continued.

Exchangeable Bases P .


!

U ) I z E, ;- -C4 P 1 4 M

Norfolk 10 138 0-6 5.71 60.0 1.75 315] 49 53 2.1 0.64 0.26 8 7 0.081 1.1 1.34 25 Lake Valencia 13 G ........ 2-5-37
f. a. 139 6-18 5.01 19.0 0.70 32 8 17 0.6 0.32 0.16 16 0 00.009 0.57 1.23 37 Wales 0.
Norfolk 11 160 0-6 5.26 31.0 1.85 194 5 55 1.0 0.56 0.24 23 14 50.023 1.01 1.83 25 Uma- Tangerine 16 P 11-?-36 2-15-37
f. s. 161 6-1 5.01 10.6 1.11 30 5 19 0.3 0.16 0.06 5 8 0 0.009 0.56 1.98 36 tilla
Norfolk 12 120 0-6 4.80 33.1 1.86 2C6 8 53 1.8 0.64 0.12 272 14 110.024 1.14 1.63 28 Lake Pineapple 12 P .......
f. s. 121 6-1 4.75 9.3 0.70 20 1 8 0.3 0.32 0.12 38 2 0 0.007 0.44 1.59 36 Alfred O.
Norfolk 13 122 0-6 6.20 93.5 1.86 600 49 32 2.7 0.48 0.50 160 8 17 0.038 1.27 1.47 19 Avon Pineapple 5? P ........ 2-4-37
f. s. 123 6-18 4.85 14.3 0.74 28 5 12 0.4 0.32 0.20 32 2 0 0.009 0.56 1.32 36 Park 0.
Norfolk 14 206 0-5 5.55 45.8 1.87 316 5 37 0.9 0.48 4.2 452 13 150.036 1.05 1.78 17 Plym- Seedling 40+ P 12--36 3-2-37
f. s. 207 5-18 5.19 22.7 0.92 7 3 16 0.2 0.40 3.0 80 9 18 0.010 0.45 2.04 26 south O.
Norfolk 15 288 0-5 6.15 73.8 1.98 435 72 58 0.6 0.24 0.60 2011 60.026 0.96 2.07 21 Alturas Valencia 25 P ........ 4-19-37
f. s. 289 5-18 4.85 11.0 1.13 31 3 28 0.0 0.24 0.24 64 9 00.009 0.55 2.05 35 0.
Norfolk 16 118 0-6 4.79 33.5 2.02 230 9 49 2.2 0.64 0.20 231 14 3 0.024 1.17 1.73 28 Lake Pineapple 12 P ...
f. a. 119 6-18 4.75 10.5 0.71 20 4 8 0.5 0.32 0.12 38 3 00.008 0.46 1.55 33 Alfred O.
Norfolk 17 158 0-6 5.14 27.0 2.03 182 5 55 1.4 1.4 4.00 192 14 17 0.026 1.05 1.93 23 Uma- Pineapple 16 P 11-?-36 2-15-37
f. s. 159 6-1 4.80 12.5 1.22 40 5 25 0. 0.4 0.64 64 8 0.010 0.62 1.97 36 tilla 0.
Norfolk 18 302 0-6 4.95 38.8 2.03 238 27 57 4.7 1.8 0.68 260 12 40.030 1.41 1.44 27 Daven- Valencia 13 G 2-?-36 4-21-37
s. 303 6-18 4.61 14.5 0.85 36 2 20 1.0 0.32 0.22 32 3 50.009 0.73 1.17 47 port 0.
Norfolk 19 192 0-8 5.09 37.5 2.13 280 1 38 3.6 0.80 0.06 48 1 0.036 1.10 1.94 18 Lees- Pineapple 20 E 12-10-36 2-24-37
f. s. 193 8-18 4.54 17.1 1.08 55 5 20 1.7 0.40 0.04 51 8 010.010 0.42 2.57 24 burg 0.
Norfolk 19V 194 0-6 4.84 10.5 2.02 61 8 19 2.7 0.48 0.04 13 0.019 0.93 2.17 28 Lees- Virgin 2-24-37
f. s. 195 6-1 5.41 9.0 0.89 20 3 13 0.8 0.16 0.04 22 1 00.007 0.41 2.17 34 burg Soil
Norfolk 20 188 0-7 5.20 23.0 2.18 149 16 48 3.0 0.40 0.12 35 6 3 0.025 1.45 1.50 34 Lees- Hamlin 9 P 2-13-37 2-24-37
s. 189 7-18 5.36 14.4 1.01 43 5 14 0 0.32 0.10 16 0.5 0 0.010 0.74 149 43 burg 0.
Norfolk 21 180 0-5 4.85 29.6 2.20 20 22 37 4.5 5.60 3.00 176 10 0.031 1.23 180 23 Lees- Temple 16 G 11--36 2-19-37
f. 181 5-1 4.56 8.1 1.16 221 3 18 1.7 0.48 0.50 48 3 0 .011 0.58 2.00 31 burg 0.











TABLE 1.-CHEMICAL ANALYSES OF THE MAJOR CITRUS GROVE SOILS OF FLORIDA (1937 SURVEY)--Continued.

d Exchangeable Bases P ilp I

0 f e- go .3.8

55 0 I o a 4 00 I

Norfolk s. 22 184 0-8 4.94 60.0 2.21 480 13 43 11.6 1.60 0.36 592 15 17 0.042 1.27 1.74 18 Min- Parson 35 G 12-15-36 2-19-S7
(hammock 185 8-18 4.84 38.5 1.41 192 5 30 3.0 0.80 0.14 64 13 6 0.016 0.66 2.14 24 neola Brown O.
phase)
Norfolk 23 126 0-6 5.99 85.0 2.31 652 69 36 3.0 0.56 0.24 294 8 22 0.045 1.41 1.64 18 Avon Pineapple 20? E ....... 2-4-37
f. s. 127 6-18 5.11 21.5 0.68 40 8 11 0.4 0.32 0.18 32 1 10 0.008 0.57 1.20 41 Park O.
Norfolk 24 804 0-6 6.24 75.0 2.36 560 72 59 1.8 0.48 0.94 240 10 3 0.034 1.33 1.78 23 Way- Valencia 20 E 2-10-37 4-22-37
s. 305 6-18 4.85 12.0 0.84 28 2 20 0.1 0.32 1.40 48 8 3 0.008 0.44 1.91 32 erly 0.
Norfolk 25 308 0-6 6.59 90.5 2.37 720 67 56 1.7 0.24 0.60 400 9 5 0.036 1.45 1.64 23 Way- Valencia 20 G ........ 4-22-37
s. 309 6-18 5.34 22.5 0.75 431 8 23 0.1 ND ND 48 6 2 3.007 0.59 1.27 49 erly 0.
Norfolk 26 210 0-6 5.31 50.5 2.41 450 13 37 2.1 0.40 0.08 600 13 8 0.038 1.33 1.82 20 Gotha Valencia 20 F ........ 3-3-37
f. s. 211 6-18 5.00 14.0 1.28 60 2 18 0.4 0.24 0.06 70 7 2 0.012 0.65 1.97 31 0.
Norfolk 27 196 0-6 5.66 68.5 2.44 580 38 53 1.8 0.32 0.80 388 10 11 3.043 1.47 1.66 20 Apopka Valencia 18 P 2-15-37 3-2-37
f. s. 197 6-18 5.05 21.3 1.03 73 2 25 0.2 0.24 0.36 64 5 1 3.010 0.50 2.06 29 0.
Norfolk 28 134 0-6 5.94 68.5 2.45 492 71 100 2.3 0.48 0.24 304 14 4 0.038 2.21 1.11 34 Lake Valencia 16 P ........ 2-5-37
f. s. 135 6-18 4.95 13.1 1.24 38 10 20 0.7 0.48 0.16 80 8 00.011 0.60 2.07 32 Wales O.
Norfolk 29 182 0-5 4.60 20.6 2.49 174 11 21 2.8 2.40 0.12 198 11 0 3.033 1.37 1.82 24 Lees- Temple 16 F 11-?-36 2-19-37
f. s. 183 5-18 4.64 12.6 1.29 48 5 17 1.8 0.32 0.10 42 2 0 0.011 0.64 2.02 34 burg 0.
Norfolk 30 218 0-6 4.94 25.3 2.50 200 11 67 2.1 0.48 0.26 154 11 26 3.039 1.41 1.77 21 Dade Seedy 14 P 2-27-57 5-4-37
f. s. 219 6-18 4.55 7.8 1.35 25 2 28 0.3 0.24 0.16 71 3 12 0.012 0.65 2.08 31 City Gft.
Norfolk 31 136 0-6 5.50 52.5 2.51 420 32 110 4.7 0.64 0.16 368 13 5 0.039 1.61 1.56 24 Lake Valencia 15 E ........ 2-5-37
f. s. 137 6-18 5.30 17.2 1.03 56 1 23 0.9 0.32 0.12 48 2 1 .012 0.61 1.69 29 Wales O.
Norfolk 32 176 0-5 5.24 38.8 2.56 274 56 58 4.1 3.20 0.08 106 7 9 3.039 1.73 1.48 26 Lees- Hamlin 16 G 12-?-36 2-19-37
f. s. 177 5-18 4.74 11.5 1.38 40 8 18 1.5 0.32 0.08 32 1 4 3.013 0.95 1.45 42 burg 0.
Norfolk 33 249 0-6 6.05 72.0 2.70 700 29 57 1.2 0.32 0.84 362 8 15 3.045 1.70 1.59 22 Sebring Valencia 18 F ...... 3-19-37
f. s. 250 6-18 5.34 13.3 0.93 36 2 22 0.1 0.24 0.24 48 4 0 0.009 0.70 1.33 45 0.








TABLE 1.-CHEMICAL ANALYSES OF THE MAJOR CITRUS GROVE SOILS OF FLORIDA (1937 SURVEY)--Continued.

Nork Exchangeable Bases P


f.s. 44 120 61 0.66 ta O.
o3 s g ,* a as s x s e. g s gg o go 'a
U to M B Q (t| Z K Q z 0 44 o .1 W DaO

Norfolk 34 257 0-6 6.14 100.0 2.90 1100 76 92 3.0 0.40 0.44 1160 1 35 0.05 1.67 1.74 18 Lucerne Seedy 254 P 2- -37 3-29-37
f. s. 258 6-18 4.71 31.0 1.11 105 11 27 0.7 0.48 0.12 93 11 12 0.009 0.43 2.58 28 Park Gft.
Norfolk 35 178 0-5 5.14 48.8 2.96 500 21 78 3.2 0.40 0.30 900 16 13 13.042 1.70 1.74 23 Lees- Valencia 18 P 11-7-36 2-19-37
f. s. 179 5-18 4.69 1 1.81 76 3 29 1. 0.32 0.36 86 13 3 0.031 0.80 2.26 15 burg 0.
Norfolk 36 170 0-5 5.84 70.0 2.99 705 67 46 1.8 0.32 0.48 735 14 770.04 1.0 2.00 18 ma- Pineapple 20 P ....... 2-18-37
f. s. 171 5-18 4.44 12.0 1.64 63 6 11 0.4 0.40 0.40 118 10 18 0.013 0.66 2.48 29 tilla 0.
Norfolk 37 202 0-5 6.35 92.0 3.10 1010 57 70 6.0 0.48 0.64 1080 12 9 0.053 1.68 1.85 18 Apopka Seedling 40+ P 1-.-37 3-2-37
f. s. 203 5-18 5.69 48.2 1.32 212 13 41 2.1 0.32 0.16 122 8 30.014 0.70 1.88 29 0.

Norfolk 38 208 0-6 5.81 57.8 3.10 655 24 41 2.1 0.32 0.56 500 12 13 .046 1.53 2.02 19 Gotha Valencia 20 P ........ 3-3-37
f. s. 209 6-18 5.19 17.9 1.47 93 3 14 0.3 0.24 0.14 80 4 2 0.014 0.76 1.94 31 0.
Norfolk 39 132 0-6 5.45 56.0 3.19 567 64 87 2.8 0.64 0.18 368 11 2 0.042 1.70 1.88 23 Lake Valencia 16 P ........ 2-5-37
f. s. 133 6-18 4.75 11.1 1.27 36 6 19 0.8 0.56 0.12 64 5 0 3.013 0.75 1.70 33 Wales O.
Norfolk 40 204 0-6 4.96 64.2 3.21 731 35 4014.7 2.40 0.18 400 16 57 3.051 1.70 1.89 19 Plym- Seedling 40+ G 2-20-37 3-2-37
f. s. 205 6-18 5.04 29.5 1.20 118 6 23 1.7 0.64 0.12 93 8 5 0.010 0.59 2.03 34 south 0.
Norfolk 41 280 0-7 5.49 65.0 3.87 596 46 63 1.6 1.10 0.24 400 17 6 1.039 1.80 1.88 27 Lake Valencia 20 G 4-17-37
f. s. 281 7-18 4.69 14.5 1.27 50 5 29 1.0 0.32 0.18 87 15 0.009 0.51 2.50 33 Alfred O.
Norfolk 42 172 0-5 5.35 44.0 3.40 428 63 128 4.3 1.20 0.08 432 11 11 1.040 1.88 1.81 27 Uma- Pineapple 15 G 11-25-36 2-18-387
f. B. 173 5-18 4.75 11.0 1.50 35 6 39 1.5 0.64 0.08 70 3 6 0.010 0.82 1.83 48 tilla 0.
Norfolk 43 245 0-6 6.49 100.0 3.43 1280 56 94 0.3 0.08 0.36 304 12 11 1.058 2.13 1.61 21 Cocoa Pineapple 14 P 12-10-36 8-13-37
f. s. 246 6-18 5.89 40.8 1.15 142 15 44 0.1 0.16 0.06 58 3 0 0.010 0.60 1.92 35 0.
Norfolk 44 212 0-6 4.64 30.7 3.48 356 14 92 2.4 0.80 2.60 187 13 201.045 2.16 1.61 28 Winder- Pineapple 14 P 2-14-37 3-3-37
f. a. 213 6-18 4.40 8.4 1.90 45 2 31 0.7 0.48 0.12 42 0 9 0.014 1.03 1.85 43 mere 0.
Norfolk 45 190 0-7 5.24 27.6 3.63 305 27 98 4.3 0.40 0.08 72 5 9 0.041 2.43 1.50 34 Lees- Hamlin 9 F 2-13-37 2-24-37
f. s. 191 7-18 5.34 23.6 1.65 96 27 29 0.8 0.08 0.04 6 0 0 0.012 1.25 1.35 60 burg 0.
Norfolk 46 255 0-6 5.75 98.0 3.68 1220 95 125 3.0 0.32 0.40 1480 18 89 0.068 1.93 1.91 19 Lucerne Seedy 25 G 2- -37 3-29-37
f. s. 256 6-18 4.64 33.3 1.05 100 1 40 0.6 0.24 0.12 100 11 10 3.009 0.43 2.44 28 Park Gft.











TABLE 1.-CHEMICAL ANALYSES OF THE MAJOR CITRUS GROVE SOILS OF FLORIDA (1937 SuRVEY)-Continued.

Exchangeable Bases P

a -
z a *
"0 0 - a0 so w 'O 0 0 *
m C 2 m Q M N N Z ;1 0 uu CO O0

Norfolk 47 251 0-6 5.45 80.2 3.70 1065 27 130 17. 1.10 0.80 1840 25 24 0.062 2.03 1.82 19 Winter Valencia 41 G 11-5-86 3-19-37
f. s. 252 6-18 5.10 45.8 1.24 194 6 43 0.9 0.32 0.22 131 11 7 0.010 0.62 2.00 36 Haven O.
Norfolk 48 130 0-7 5.69 60.0 3.78 6 21 2 1 152 0.2 1.6 0.20 32 14 3 0.04 1.91 1.98 26 Lake Valencia 16 P 2-5-37
f. s. 131 7-18 4.99 14.6 1.84 58 18 39 0.5 0.96 0.14 48 3 0 0.014 1.04 1.77 43 Wales 0.
Norfolk 49 247 0-6 5.51 80.8 3 80 130 54 270 2.6 0.32 0.16 760 29 31 0.073 2.47 1.54 20 Cocoa Valencia 35 G 2-10-37 3-13-37
f. s. 248 6-18 4.76 26.1 1.65 134 5 60 0.1 0.16 0.08 12 14 40.011 0.61 2.70 32 0.
Norfolk 50 278 0-7 5.66 65.0 3.99 88: 65 9 1.7 1.60 0.52 1040 19 8 0.053 1.97 2.02 22 Lake Valencia 25 ........ 4-17-37
f. s. 279 7-18 4.75 22.5 1.86 124 15 38 0.5 0.40 0.18 128 15 0 0.011 0.86 2.16 45 Alfred 0.
Norfolk 51 128 0-7 5.16 49.5 4.04 568 87 175 2.0 1.6 0.20 27 21 40.044 2.31 1.75 30 Lake Valencia 16 G ........ 2-4-37
f. s. 129 7-18 4.90 18.1 1.98 8i 19 6 0.6 0.96 0.16 80 5 1 0.017 1.08 1.83 37 Wales O.
Norfolk f.s. 52 186 0-6 5.66 64.0 4.35 90 51 156 12.1 0.64 0.46 60 21 260.055 2.07 2.10 22 Cler- Seedling 40- P 2-19-37
(hammock 187 6-18 4.85 21.3 2.61 169 10 68 5.3 0.80 0.40 144 22 5 0.022 1.08 2.41 28 month 0.
phase)
Norfolk f.s 53 200 0-7 6.35 68.5 4.97 1249 24 1 .2 0.32 0.10 326 10 50.047 2.24 2.21 28 Ocoee Pineapple 18 E 1-?-37 3-2-37
(hammock 201 7-18 5.21 16.0 2.64 13 8 42 1.4 0.24 0.08 96 2 9 0.016 1.40 1.88 51 0.
phase) I
Norfolk 54 220 0-6 4.90 17.5 5.00 256 29 85 2.0 0.32 0.24 150 4 18 0.064 3.10 1.61 28 Dade Seedy 14 G 2-27-37 3-4-37
f. s. 221 6-18 4.54 7.0 1.90 3 2 29 0.9 0.16 0.14 16 0.5 13 0.015 1.35 1.41 52 City Gft.
Norfolk f.s. 54V 222 0-5 5.55 20.0 4.45 25 5 23 1.1 0.32 0.14 49 3 0 0.042 2.53 1.76 35 Dade V:rgin 3-3-37
(hammock 223 5-18 5.81 15.1 2.73 116 27 1 0.3 0.16 0.12 42 1 00.020 1.66 1.65 48 City Soil
phase)
Nor olk 55 284 0-8 5.29 32.5 6.25 655 38 162 9.3 0.32 0.20 290 19 60.052 262 2.39 29 Home- Valencia 20 E 2-?-37 4-17-37
v. f. s. 285 8-18 5.05 12.7 3.04 122 6 43 1.6 0.24 0.10 80 1 00.016 1.45 2.10 53 land O.

Blanton 56 310 0-9 6.19 68.5 3.51 85 18 175 1.2 0.16 0.12 20 10 80.040 1.99 1.77 29 Auburn- Seey 18 P 1-28-7 4-22-37
f. s. 311 9-18 5.04 7.6 2.12 3 35 0.8 0.24 0.08 40 3 0.014 0.91 2.33 38 dale Gt.

Blanton 57 168 0-7 5.90 63.0 3.74 82 43 97 7.5 2.0 0.22 625 18 15 0.039 1.45 2.58 22 Uma- Seedling 42 E 12-1-36 2-18-37
f. a. 169 7-18 5.39 25.5 1.78 144 13) 31 1.5 0.32 0.04 112 17 0.010 0.65 2.74 38 tilla 0.








TABLE 1.-CHEMICAL ANALYSES OF THE MAJOR CITRUS GROVE SOILS OF FLORIDA (1937 SURVEY)-Continued.








Blanton 8 166 0-6 5.84 66.0 3.89 87 7 66 2.5 1.1 0.68 518 17 33 0.049 1.87 2.08 22 Uma- Pineapple 18 P ........ 2-18-37
f. s. 167 6-18 4.71 17.2 1.81 9 31 0.7 0.32 0.36 102 15 10 .010 0.65 2.80 38 tilla O.
Z .5




Blanton 58 166 0-6 .841 17 0.049 1.87 2.08 22 U Pineapple 18 P ........ 2-18-37
f.s. 167 6-18 4.71 17.2 1.81 96 8 31 0.7 0.32 0.36 102 15 10 0.010 0.65 2.80 38 tilla 0.
Blanton 59 243 0-6 5.54 43.5 4.12 650 22 73 0.3 0.32 0.06 960 23 6 0.048 1.88 2.20 23 DeLand Pineapple ? E 3-12-37
f. s. 244 6-18 4.59 22.1 3.44 281 42 0.1 0.32 0.06 205 21 0 0.018 1.47 2.34 47 0.
Blanton 60 253 0-6 5.54 75.0 4.18 1070 78 11 3.1 0.88 0.62 735 19 39 .057 1.85 2.26 19 Lucerne Seedy 25 P 2-7-37 3-29-37
f. s. 254 6-18 4.49 20.0 1.70 101 11 34 0.7 0.56 0.30 112 14 14 0.013 0.69 2.46 31 Park Gft.
Blanton 61 241 0-6 5.49 40.2 4.70 605 49 13 5.0 0.32 0.14 336 11 1410.049 2.31 2.03 27 DeLand Hamlin 20 E 2-7-87 3-11-37
f. s. 242 6-18 5.16 11.3 2.66 94 3 41 1.0 0.16 0.06 80 2 010.020 1.62 1.64 47___ 0. ____ _____ _

Eustis 62 162 0-6 5.64 51.7 2.84 485 3 94 2.5 0.32 0.04 432 15 9 0.034 1.46 1.95 25 Eustis Valencia 12 P 12-1-36 2-17-37
f. s. 163 6-18 5.09 17.1 1.56 81 6 28 1.7 0.24 0.04 58 5 2 0.012 0.72 2.17 35 0.
Eustis 63 174 0-7 6.20 89.5 2.97 948 54 56 3.8 0.32 0.32 480 12 15 0.055 1.72 1.7 18 Tavares Seedling 45 G 2-18-37
f. s. 175 7-18 5.50 51.0 1.98 353 19 38 4.7 0.16 0.08 14611 20.018 0.96 2.06 31 0.
Eustis 64 164 0-6 6.39 85.2 3.32 990 5 20 8.5 0.40 0.80 1480 18 7 0.060 1.58 2.10 15 Eustis Seedling 42 F 12-1-36 2-17-37
f. s. 165 6-18 5.74 64.0 1.64 363 1 61 3.9 0.16 0.06 128 19 6 0.011 0.58 2.83 31 0.
Eustis 65 286 0-7 6.29 80.0 5.27 1460 83 19 1.7 0.24 0.30 760 18 110.067 2.37 2.22 21 Home- Seedling 55 G 2-?-37 4-17-37
f. a. 287 7-18 5.56 32.1 2.82 296 13 88 1.0 0.16 0.08 120 16 3 0.041 1.12 2.51 16 land 0.
Eustis f.s. 66 282 0-8 5.69 51.2 6.46 112 59 20 2.8 1.4 0.22 530 13 40.060 3.18 2.03 31 Bartow Seedling 55 E 4-17-37
(dark- 283 8-18 5.00 19.5 3.60 221 7 9 1.9 0.48 0.12 120 0 00.023 2.12 1.70 53 0.
colored
phase) _____ ______________

Lakewood 67 238 0-6 6.00 77.5 3.24 880 54 73 1.2 0.16 0.22 397 17 20 0.057 1.67 1.94 17 Orange Seedling 55 F ........ 3-11-37
f. s. 239 6-12 5.54 33.9 0.92 101 5 30 0.1 0.24 0.10 4 8 4 0.016 0.47 1.95 17 City 0.
240 12-18 4.54 17.2 1.44 65 6 46 0.1 0.40 0.08 96 7 0.013 0.70 2.06 31
Lakewood 68 263 0-7 6.74 100.0 5.65 2160 105 78 0.7 0.08 0.12 6 15 8 0.067 2.18 2.59 19 Braden- Valencia 20 F 2-7-37 4-6-37
f. s. 264 7-18 6.04 59.0 2.61 532 34 57 0.1 0.08 0.06 246 13 00.017 0.86 3.04 29 ton O.

Orlando 69 216 0-6 5.46 20.8 3.58 252 16 37 1.5 0.32 0.06 58 4 4 0.039 2.02 1.77 30 Orlando Pineapple 8 1-1-37 3-3-37
f. s. -217 6-1 5.19 58.5 2.27 38 3 19 1.7 0.16 0.12 22 0 210.020 1.37 1.66 40 0.








TABLE 1.-CHEMICAL ANALYSES OF THE MAJOR CITRUS GROVE SOILS OF FLORIDA (1937 SURVEY)-Continued.

Exchangeable Bases P i





Orando 70 214 0-1 .16 15.1 6.62 329 10 106 2.5 0.32 0.12 2
a 21 ic 0.
C a P ; PQ Q 0 4





Of..rl 227 6-18 5.36 156.6 .2 329 10 106 2.9 0.08 0.60 0 7 3 .0 .6 1.31 -1-37 3-3-7

Gainesville 7 22 0-6 6.09 396 .4 6.8 795 141 79 5 0.7 0.24 08 49 5 0 .066 4.60 1.45 40 Dade Virgin ........ 3-4-37
f. a. 225 6-18 5.20 21.7 5.70 242 21 84 1.3 0.08 0.06 39 0 5 3.022 2.66 1.39 70 City 0.

Lf. 227 6-18 5.36 16.6 4.82 218 39 72 0.9 0.08 0.60 59 0 7 3.083 5.68 1.11 68 City 0.
Gainesville 72V 228 0-6 6.09 09.6 6.65 795 141 02 0.7 0.08 0.08 49 3 0 1066 4.60 1.45 40 Dade Virgin 3-4-37
f. s. 229 6-18 6.09 20.8 4.10 238 55 26 0.3 0.08 0.06 9 1 0 ).030 3.10 1.32 60 City Soil

Portsmouth 73 274 0-8 4.55 42.7 2.95 440 21 58 3.3 1.4 0.16 64 39 0 1.047 1.52 1.94 19 Pal- Seedy 25 P 12- ?-36 4-7-37
f. s. (hard- 275 8-18 4.36 67.5 0.80 172 13 44 0.8 0.96 0.08 16 11 0 3.012 0.55 1.45 27 metto Gft.
pan phase)
o Portsmouth 74 276 0-8 5.94 86.0 3.70 1140 45 102 1.8 0.16 0.24 465 20 43.061 1.58 2.34 15 Braden- Seedy 25 E 12-7-36 4-7-37
00 f. s. 277 8-18 5.51 82.5 11.0 2650 495 332 1.7 0.16 0.06 2280 47 0 0.033 1.41 7.80 25 ton Gft.
Portsmouth 75 150 0-11 5.64 66.5 3.73 775 102 80 1.7 0.32 0.122 8 7 0.046 1.87 2.00 24 Vero Valencia 18 P 2-1-37 2-12-37
f. s. 151 11-24 5.30 55.5 0.87 148 21 22 0.7 0.48 0.10 10 4 2 .011 0.53 1.65 28 Beach O.
Portsmouth 76 154 0-12 5.26 55.0 5.48 910 133 140 5.1 0.24 0.12 26 13 6 3.054 2.14 2.56 23 Vero Marsh 18 G 2-1-37 2-12-37
f. s. 155 12-18 5.06 54.5 0.86 152 16 19 0.5 0.48 0.12 10 3 2 .011 0.56 1.54 30 Beach Gft.
Portsmouth 77 156 0-18 5.14 62.5 9.35 1860 236 171 1.1 0.40 0.14 33 1 20 .124 3.29 2.84 15 Vero Marsh 6 E 1-?-37 2-13-37
f. s. Beach Gft.

Parkwood 78 270 0-10 5.24 52.8 3.62 635 59 72 2.6 1.60 1.2 48 13 0 1.059 1.86 1.95 18 Braden- Seedy 9 P 12-?-36 4-7-37
f. s. 271 10-24 5.24 77.0 1.18 304 24 37 2.5 0.72 0.14 32 10 0 3.019 0.58 2.04 20 ton Gft.
Parkwood 79 261 0-7 5.74 66.8 3.70 890 16 138 2.6 2.20 0.32 384 25 9 13.060 1.51 2.45 15 Braden- Seedy 20 G ....... 4-6-37
f. s. 262 7-14 4.81 48.7 2.42 384 29 76 5.2 0.56 0.10 55 17 0 3.016 0.50 4.85 18 ton Gft.
Parkwood 80 259 0-7 6.26 89.0 4.58 1430 73 136 6.1 0.64 0.22 476 15 8 13.073 1.81 2.53 14 Braden- Seedy 25 P 12- ?-36 4-6-37
f. s. 260 7-14 5.70 79.5 3.00 772 86 64 11.5 0.32 0.10 80 13 1 3.017 0.55 5.45 19 ton Gft.
Parkwood 81 265 0-7 6.25 96.5 4.75 1680 7 692.7 0.08 0.12 545 15 7 3.070 1.90 2.50 16 Braden- Seedy 50 G 4-?-36 4-6-37
s. 266 7-14 5.41 75.0 3.82 895 130 74 6.1 0.32 0.06 592 24 0 3.018 0.67 5.70 22 ton Gft.
267 14-24 6.84 100.0 13.2 3680103 24 1.7 0.16 0.06 3200 33 0 0.030 1.81 7.30 35









TABLE 1.-CHEMICAL ANALYSES OF THE MAJOR CITRUS GROVE SOILS OF FLORIDA (1937 SURVEY)-Concluded.

Exchangeable Bases P 4 a

i d |

*I 2 N Q M 0 A I

Parkwood 82 272 0-10 4.88 52.7 5.46 985 57 148 1.5 0.48 0.08 96 34 6 0.070 2.32 2.35 19 Braden- Seedy 9 E 12-?-36 4-7-37
f. s. 273 10-24 4.88 46.0 4.05 528 86 150 0.8 0.96 0.12 192 17 0 ).029 1.23 3.30 25 ton Gft.
Parkwood 83 148 0-7 6.20 83.0 5.75 1320 266 307 2.8 0.24 0.12 144 6 22 3.073 2.44 2.36 19 Vero Marsh 6 G 2-1-37 2-12-37
f. s. loam 149 7-13 6.40 82.5 3.20 625 194 228 1.5 0.24 0.12 19 1 70.034 1.35 2.37 23 Beach Gft.
Parkwood 84 157 0-8 8.31 100.0 6.60 2070 284 210 0.4 0.16 0.36 13 0 97 0.125 3.05 2.16 14 Vero Marsh 7 G 1-7-37 2-13-37
clay loam Beach Gft.
Parkwood 85 142 0-8 5.46 64.5 6.95 1300 227 196 9.3 0.32 0.14 129 9 18 0.016 2.79 2.49 10 Vero Seedy 18 G 2-1-37 2-11-37
s. loam 143 8-18 6.50 79.5 5.72 1210 347 .93 0.8 0.32 0.10 20 0 6 0.038 2.22 2,58 34 Beach Gft.
144 18-24 8.16 100.0 14.0 3950 950 200 0.6 0.16 0.12 10 0 2 3.076 5.25 2.69 40
Parkwood 86 147 0-12 6.26 95.0 7.68 2240 310 301 3.9 0.16 0.12 88 9 24 0.095 2.54 3.02 16 Vero Valencia 6 P 2-1-37 2-12-37
s. loam Beach O.
Parkwood 87 152 0-12 8.11 100.0 7.85 2300 465 175 1.3 0.16 0.26 26 0 101 1.209 4.33 1.82 12 Vero Seedy 18 P 2-1-37 2-12-37
clay loam 153 12-18 8.20 100.0 3.06 725 272 113 0.4 0.16 0.18 10 0 8 3.098 2.52 1.22 15 Beach Gft.
Parkwood 88 232 0-8 6.00 82.5 9.00 2660 132 154 6.6 0.16 0.10 108 11 5 3.109 3.42 2.63 18 Wild- Pineapple ? G 6-?-36 3-5-37
f. s. loam 233 8-18 8.29 100. 17.7 6250 445 209 0.3 0.08 0.12 13 0 4 ).072 4.30 4.12 35 wood O.
Parkwood 89 236 0-6 6.44 100. 11.6 4350 117 198 1.8 0.16 0.30 745 26 7 0.172 3.80 3.05 13 Titus- Pineapple 21 G 12- ?-36 3-10-37
loamy f. s. 237 6-14 6.66 100. 4.72 1760 52 67 0.6 0.08 0.12 109 13 11 3.048 1.20 3.95 14 ville O.
Parkwood 90 230 0-8 6.94 98.5 14.7 5450 183 261 5.3 0.16 0.10 216 11 5 3.130 3.70 4.00 16 Wild- Parson 40 G 6- -36 3-5-37
f. s. loam 231 8-16 8.19 100. 27.6 9700 750 122 0.3 0.08 0.08 10 0 4 1.076 5.42 5.08 41 wood Brown O.
Parkwood 91 145 0-6 7.86 100. 17.9 6450 347 313 0.8 0.16 0.24 25 1 375 0.517 10.6 1.70 12 Vero Seedy 18 P 2-1-37 2-11-37
loam 146 6-18 8.19 100. 6.63 2200 215 195 0.3 0.16 0.18 10 0 154 3.219 4.95 1.34 13 Beach Gft.
Parkwood 92 234 0-6 7.81 100. 19.3 7000 308 416 0.3 0.08 0.80 214 5 33 3.389 8.90 2.17 13 Titus- Pineapple 21 P 12-?-36 3-10-37
f. a. loam 235 6-18 8.35 100. 4.10 1330 139 178 0.6 0.08 0.20 22 0 13 0.086 2.35 1.75 16 ville 0. _

Bladen 93 268 010.45 69.5 5.31 121 73 250 26.6 0.56 0.14 1240 36 6.065 1.68 3.16 15 Braden- Valencia 26 F 12- ?-36 4-6-37
f. loam 269 10-24 5.86 86.5 21.6 5700 795 85512.0 0.16 0.06 3160 96 010.040 2.25 9.60 33 ton O. _










TABLE 2.-MINIMUM, MAXIMUM AND AVERAGE AMOUNTS OF VARIOUS CONSTITUENTS FOUND IN DIFFERENT CITRUS GROVE
SOILS (1937 SURVEY).
Base S Exch. D Pounds per Acre-Six-Inches of Soil T I
Soil No. of Base Exh. Total Oranic Ratio atio
Series Sam- Depth pH Satu- Cap. Exchangeable Bases P N- N Matter _Ex-CaP C:N
ie M1N Matter Ex.Cap. C N
ples ration m.e./ M I | [ Ac id Water trate %I % % O.M.I
S______%100 g. CaM M Zn Cu Sol. Sol. N I ___

in. 4.60 17.5 1.39 149 21 0.2 0.08 0.06 35 4 0 0.020 0.89 1.11 17
55 Surface Max. 6.59 100.0 6.25 1240 121 270 17.0 5.60 4.20 1840 29 77 0.073 3.10 2.39 34
Norfolk Soil Aver. 5.56 57.3 2.72 520 39 73 3.2 0.91 0.55 408 12 13 0.039 1.56 1.73 23
Min. 4.29 7.0 1 0.68 20 1 8 0.0 0.08 0.04 6 0 0 0.007 | 0.42 1.17 15
55 Subsoil Max. 5.89 48.2 3.04 212 27 68 5.3 0.96 3.00 144 22 18 0.031 1.45 2.70 60
Aver. 5.03 17.8 1.26 66 6 26 0.8 0.36 0.26 61 6 3 0.011 0.70 1.84 36

Min. 5.49 40.2 3.51 605 18 66 0.3 0.16 0.06 200 10 6 0.039 1.45 2.03 19
6 Surface Max. 6.19 75.0 4.70 1070 78 175 7.5 2.0 0.68 960 23 39 0.057 2.31 2.58 29
Blanton Soil Aver. 5.75 59.4 4.02 812 47 110 3.3 0.80 0.31 566 16 19 0.047 1.90 2.23 24
Min. 4.49 | 7.6 1.70 40 2 31 0.1 0.16 0.04 40 2 0 0.010 0.65 1.64 31
S6 Subsoil Max. 5.39 22.1 3.44 281 13 42 1.5 0.56 0.36 205 21 14 0.020 1.62 2.80 47
Aver. 4.90 17.3 2.25 126 7 36 0.8 0.32 0.15 109 12 4 0.014 1.00 2.40 40

Min. 5.64 51.2 2.84 485 34 56 1.7 0.24 0.04 432 12 4 0.034 1.46 1.73 15
5 Surface Max. 6.39 89.5 6.46 1460 83 208 8.5 1.40 0.80 1480 18 15 0.067 3.18 2.22 31
Eustis Soil Aver. 6.04 71.5 4.17 1001 56 150 3.9 0.54 0.34 740 15 9 0.055 2.06 2.00 22
S Min. 5.00 17.1 1.56 81 6 28 1.0 0.16 0.04 58 0 2 0.011 0.58 1.70 16
5 Subsoil Max. 5.74 64.0 3.60 363 19 88 4.7 0.48 0.12 146 19 6 0.041 2.12 2.83 53
Aver. 5.38 36.7 2.32 263 12 62 2.6 0.24 0.08 115 11 3 0.021 1.10 2.25 33
____ i_ ___ _== = -
Min. 6.00 77.5 3.24 880 64 73 0.7 0.08 0.12 397 15 8 0.057 1.67 1.94 17
2 Surface Max. 6.74 100.0 5.65 2160 105 78 1.2 0.16 0.22 625 17 20 0.067 2.18 2.59 19
Lakewood Soil Aver. 6.37 88.7 4.45 1520 79 76 0.9 0.12 0.17 514 16 14 0.062 1.93 2.27 18
Min. 4.54 5.9 0.92 65 5 30 0.1 0.08 0.06 48 7 0 0.013 0.47 1.95 17
3 Subsoil Max. 6.04 33.9 2.61 532 34 57 0.1 0.40 0.10 248 13 4 0.017 0.86 3.04 31
Aver. 5.37 19.0 1.66 233 15 44 0.1 0.24 0.08 131 9 1 0.015 0.68 2.35 26

*Arithmetical average of pH values rather than of the actual hydrogen ion concentration.







TABLE 2.-MINIMUM, MAXIMUM AND AVERAGE AMOUNTS OF VARIOUS CONSTITUENTS FOUND IN DIFFERENT CITRUS GROVE
SOILS (1937 SURVEY)-Concluded.


N. of Base IExch. Exchangeable Bases P Total Organic Ratio: Ratio
Soil Sam DepthH atu- Cap. Ni- Matter Ex.Cap C:N
Series ples ration m.e./ Acid Water trt % % 0. M.
S1% 100g. Ca Mg K I Mn Zn Cu Sol. I Sol. N I

Min. 5.16 15.1 3.58 252 10 37 1.5 0.32 0.06 58 2 4 0.039 2.02 1.63 30
2 Surface Max. 5.46 20.8 6.62 329 16 106 2.5 0.32 0.12 150 4 5 0.057 4.06 1.77 41
Orlando Soil Aver. 5.30 18.0 5.10 291 13 72 2.0 0.32 0.09 104 3 4 0.048 3.04 1.70 35
Min. 5.00 11.3 2.27 38 3 19 1.5 0.16 0.06 22 0 2 0.020 137 1.45 40
2 Subsoil Max. 5.19 58.5 4.52 165 6 56 1.7 0.16 0.12 23 0 6 0.039 3.12 1.66 46
Aver. 5.10 34.9 3.40 102 5 37 1.6 0.16 0.09 23 0.2 4 0.030 2.25 1.56 43


2 Surface Max. 5.79 41.2 8.50 1040 125 300 3.9 0.32 0.22 265 5 20 0.086 5.50 1.63 37
Gainesville Soil Aver. 5.64 40.0 7.80 938 102 275 3.1 0.28 0.21 250 4 17 0.081 4.93 1.59 35
Min. 5.20 16.6 3.70 218 21 72 0.9 0.08 0.06 39 0 5 0.022 2.66 1.81 68
2 Subsoil Max. 5.36 21.7 4.82 242 39 84 1.3 0.08 0.60 59 1 7 0.033 3.68 1.39 70
1 Aver. 5.28 19.2 4.26 230 30 78 1.1 0.08 0.33 50 0 6 0.028 3.17 1.35 69


Min. 4.55 42.7 2.95 440 21 58 1.1 0.16 0.12 26 1 0 0.046 1.52 1.94 15
5 Surface Max. 5.94 86.0 9.35 1860 236 171 5.1 1.40 0.24 465 20 20 0.124 3.29 2.84 24
Portsmouth Soil Aver. 5.31 62.5 5.04 1025 107 110 2.6 0.50 0.16 125 17 7 0.66 2.08 2.34 19
Min. 4.36 54.5 0.80 148 13 19 0.5 0.16 0.06 10 3 0 0.011 0.53 1.45 25
4 Subsoil Max. 5.51 82.5 11.00 2650 495 332 1.7 0.96 0.12 2280 47 2 0.033 1.41 7.80 30
Aver. 5.06 65.0 3.38 781 136 104 0.9 0.52 0.09 582 16 1 0.017 0.76 3.11 27

Min. 4.88 52.7 3.62 635 16 69 0.3 0.08 0.08 13 0 5 0.016 1.51 1.70 10
15 Surface Max. 8.31 100.0 19.30 7000 465 416 9.3 2.20 1.20 745 34 375 0.517 10.60 4.00 19
Parkwood Soil Aver. 6.52 85.4 8.63 2717 194 206 3.2 0.45 0.30 220 12 48 0.144 3.66 2.48 15
Min. 4.81 46.0 1.18 304 24 37 0. 0.08 0.06 10 0 1 0.016 0.50 1.22 13
13 Subsoil Max. 8.35 100.0 27.60 700 70 228 11.5 0.96 0.20 592 24 154 0.219 5.42 5.70 41
Aver. 6.68 83.7 6.71 2053 213 123 2.4 0.31 0.12 90 7 16 0.059 2.14 3.37 25


Bladen 1 Surface 5.45 69.5 5.31 1215 73 250 27.0 0.56 0.14 1240 36 6 0.065 1.68 3.16 15
1 1 Subsoil 5.861 86.5 121.60 15700 1 795 855 12.0 1 0.16 0.06 3160 96 0 0.040 2.25 9.60 33











TABLE 3.-CHEMICAL ANALYSES OF THE MAJOR CITRUS GROVE SOILS OF FLORIDA (1942-1946 SURVEY).

SPounds per Acre-Six-Inches of Soil

1 i ^ Exchangeable Bases P Z Q ; z




Norfolk f.s. 94 312 0-5 5.89 82.2 2 668 37101 4.75 0.80 369 19.0 6 .00 1.31 1.91 15 Merritts Pineapple 21 G 4-4-46 10-4-46 1.9
313 5-20 5.40 44.4 1.40 182 29 32 1.1 0.50 0.40 184 9.0 5 0.010 0.46 3.04 27 Island 0. 2.0
Norfolk f.s. 95 314 0-5 5.18 48.8 3.40 15 30 61 5.2 12.42 1.59 706 28.8 5 0.070 1.70 2.00 14 Merritts Valencia 41 G 4-7-46 10-4-46 1.8
315 5-20 4.77 27.8 1.80 137 20 34 1.4 1.05 0.34 167 22.8 4 0.010 0.49 3.68 28 Island 0. 1.9
Norfolk f.s. 96 316 0-5 5.11 70.0 6.70 1,668 41 88 8.4 7.61 3.19 517 18.0 23 0.121 2.47 2.71 12 Merrittts Pineapple 60+ F 6-3-42 9-3-42 1.9
317 5-18 5.99 56.7 2.30 386 60 75 0.6 0.20 0.44 496 11.8 14 3.014 0.45 5.11 19 Island 0. __2.0

Blanton f.s. 97 318 0-7 6.60 92.0 3.02 1,041 101 17 1.3 0.33 1.22 242 9.0 15 0.020 1.55 1.94 45 Cocoa Val. & 30 G 4-1-43 9-2-43 2.2

-
M Lakewood 98 320 0-7 5.56 56.5 2.00 394 10 80 1.8 0.50 0.59 302 19.2 14 0.030 0.95 2.20 18 Oak Hill Valencia 1 P 12-19-42 6-5-43 2.0
f.s. 321 7-18 5.42 24.5 1.94 168 0 44 0 0. 0.32 180 2.4 5 0.015 0.88 2.20 34 0. 2.0
Lakewood 99 322 0-6 6.31 94.3 2.48 888 42 27 1.9 0.31 0.71 212 13.2 15 0.06 1.01 2.45 16 Cocoa Seedy 33 P 4-1-43 9-28-43 2.1
f.s. 323 6-24 6.15 88.7 0.62 22 10 1.1 0.33 0.35 53 5.7 10 0.012 0.25 2.48 12 Gft. 2.2
Lakewood 100 324 0-6 5.23 53.0 3.34 595 23 84 0.3 2.1 2.96 279 6.5 18 0.118 1.60 2.09 8 Oak Hill Marsh 8 G 2-7-43 6-5-43 1.9
f.s. 325 6-18 5.49 39.8 1.86 247 2 61 0.3 0.29 0.38 158 1.1 10 0.021 1.00 1.86 28 Gft. 1.9
Lakewood 101 326 0-5 4.85 20.4 3.80 209 32 54 6.8 0.38 0.49 517 18.0 15 0.060 2.03 1.87 20 Merritts Marsh 10 F 6-14-42 9-3-42 1.9
f.s. 327 5-24 4.95 60.0 0.54 3 60 1.0 0.21 0.55 42 8.8 0 .009 0.30 1.80 19 Island Gft. 2.1

Cocoa f.s. 102 328 0-6 7.39 94.0 5.02 1,636132 281 0.2 0.21 1.01 1,008 23.1 61 0.093 2.26 2.22 14 Rock- L.G.G. & 26 P 5-9-42 5-26-42 2.1
(Tentative 329 6-12 7.70 100.0 3.40 1,247 112 132 1.3 0.22 0.62 451 3.3 0 0.045 1.20 2.83 15 ledge P.A. 0. 2.2
name)
Cocoa f.s. 103 330 0-6 7.12 84.6 6.54 1,865 143 418 0 0.22 1.05 587 26.4 73 .117 2.62 2.49 13 Rock- L.G.G. & 26 G 5-9-42 5-26-42 2.2
(Tentative 331 6-12 7.60 100.0 3.04 1,146 84108 1.5 0.11 0.35 229 7.3 0 0.034 1.10 2.76 19 ledge P.A. 0. 2.2
name)_

S The following abbreviations are used in soil type: s.-sand, f.-fine.
SThe following abbreviations are used in evaluating the general grove condition: (P)-poor. (F)-fair, (G)-good. (E)-excellent.
N.D.-not determined.







TABLE 3.-CHEMICAL ANALYSES OF THE MAJOR CITRUS GROVE SOILS OF FLORIDA (1942-1946 SURVEY)--Continued.

SExchangeable Bases


""z o. &, 1| J^ | .H | ^ 4



Parkwood 10 33 0-10 6.90 100.0 3.28 1,39 4 20 1.1 0.33 0.75 136 2.2 5 0.069 1.75 1.87 15 Vero Previously ? 2-2-44 2.2
loamy f.s. 333 10-22 8.12 100.0 1.08 437 28 28 1.7 0.35 0.37 2 1.1 8 1.023 0.55 1.96 13 Beach farmed 2.3
334 22-28 8.45 100.0 0.68 266 18 71 1.0 0.11 0.5 2 0.1 6 3.006 0.80 2.26 29 2.2
Parkwood 105 331 0-12 7.81 100.0 5.40 1,776183 166 0.8 0.40 0.60 26 2.2 1 .158 2.29 2.35 8 Vero Marsh 19 E 1-15-42 2-26-42 2.0
loamy f.s, 336 12-18 8.10 100.0 3.04 1,170 160 92 0.3 0.8 0.59 3 2.0 6 0.052 1.10 2.76 12 Beach Gft. 2.0
Parkwood 106 337 0-12 7.69 100.0 6.66 1,903 191 864 0.5 0.09 0.50 81 6.7 12 .216 4.81 1.38 13 Vero Valencia 16 G 1-15-42 6-4-42 1.8
f.s. loam 3388 12-18 8.11 100.0 6.20 2,052 12 82 0.3 0.08 0.1 3 0.0 50 .08 2.02 3.07 14 Beach 0. 1.7
Parkwood 107 339 0-8 5.30 67.5 7.40 1,384 91122 8.0 2.24 0.42 394 41.6 11 0.150 3.95 1.87 15 Mims Pineapple 25 F 5-5-46 10-3-46 1.6
loamy f.s. 340 8-20 7.57 100.0 3.60 1,005 111 201 1.0 0.90 0.20 83 9.7 5 0.030 0.85 4.23 16 0. 1.8
SParkwood 108 341 0-12 7.40 100.0 7.68 1,845 391475 0.4 0.09 0.53 77 4.7 22 9.199 5.36 1.41 16 Vero Valencia 16 P 1-15-42 6-4-42 1.8
W f.s. loam 342 12-18 7.96 100.0 8.02 2,393 170 116 0.5 0.68 0.27 2 1.4 12 0.103 2.53 3.17 14 Beach 0.
Parkwood 109 343 0-12 7.71 100.0 10.46 3,465 157 115 5.4 0.6 0.58 11 2.7 21 0.105 4.55 2.30 25 Vero Marsh 13 G 5-17-42 9-18-42 1.8
f.. loam 344 2-24 7.98 37.1 5.90 644 56 99 0.4 0.18 0.29 2 1.0 0 .008 1.71 3.44 12 Beach Gft 1.8
Parkwood 110 345 0-6 7.54 100.0 11.10 3,060 109 180 0.6 0.23 0.44 207 15.0 14 93.200 4.21 2.64 12 Titus- Pineapple 29 F 5-31-46 10-3-46 1.5
f.s. loam 346 6-16 8.23 100.0 5.40 1,536 63 168 0.4 0.29 0.29 16 0. 6 0.050 0.16 83.72 2 ville 0.
Parkwood 111 347 0-10 7.62 100.0 11.20 3,032 411 2 0 0.17 0.50 64 1.0 40 0.228 5.19 2.15 13 Vero Marsh 24 P 12-15-42 1-27-4 1.7
f.s. loam 348 10-24 7.85 100.0 3.80 865 256 175 0 0.18 0.29 4 0.6 17 0.077 2.01 1.89 15 Beach Gft. 1.8
Parkwood 112 349 0-5 6.63 90.7 11.60 3,100 127 88 1.4 0.24 0.64 1,215 27.2 12 0.220 4.65 2.49 12 Titus- Pineapple 29 F 5-31-46 10-3-46 1.6
loamy f.s. 3560 5-16 7.91 100.0 3.20 1,020 54 54 0.7 0.18 0.53 184 25.2 4 3.040 0.45 7.12 7 ville 0. 1.8
Parkwood 113 851 0-7 6.79 60.0 11.70 1,854 112 117 0.9 0.22 0.51 916 36.0 9 19.230 5.54 2.11 14 Mims Pineapple 25 P 5-5-46 10-3-46 1.5
loamy f.s. 352 7-22 8.19 100.0 2.80 977 38 53 1.2 0.28 0.34 46 4.6 7 3.020 0.60 4.66 17 0. 1.9
Parkwood 114 353 0-6 7.80 100.0 11.90 3,300 11016 0.4 0.16 0.84 204 14.1 20 3.240 4.70 2.54 11 Titus- Pineapple 30 P 6-7-46 10-3-46 1.5
f.s. loam 354 6-12 8.30 100.0 7.20 1,840 57 168 0.3 0.14 0.59 7 0.8 19 0.120 2.72 2.65 13 ville 0.
(Shallow
phase)
Parkwood 115 355 0-6 7.59 99.4 12.74 3,435 165 198 0. 0.15 0.93 7 0 81 0.357 5.19 2.45 8 Merritts Navel 9 E 6-7-43 7-1-43 1.5
f.s. loam 356 6-18 7.88 100.0 2.80 1,016 28 13 0. 0.38 0.3 0 0 0 9 0.109 2.02 1.38 11 Island 0.
(Shallow
phase)










TABLE 3.-CHEMICAL ANALYSES OF THE MAJOR CITRUS GROVE SOILS OF FLORIDA (1942-1946 SURVEY)-Continued.

d Exchangeable Bases P i
z Ca Q 0 -A
a 0 B >

II I N 1 1| r i 1 i .|1 -131 20

Parkwood 116 357 0-8 8.01 100.0 14.68 3,541 841 138 0.5 0.26 0.34 23 1.6 9 0.194 5.54 2.65 16 Vero Marsh 1 F 12-13-41 2-25-421 1.7
f.s. loam 358 8-24 8.19 100.0 7.28 1,698 460 42 0.8 0.17 0.17 2 1.2 9 0.120 3.54 2.05 17 Beach Gft. 1.7
(Shallow
phase)
Parkwood 117V 35 0-6 7.70 100.0 18.48 5,649 147 6 0 0.16 0.26 10 2.1 41 0.392 7.61 2.43 11 Ft. Virgin Soil ... .... .... 8-20-43 1.6
f.s. loam 360 6-18 7.90 100.0 8.66 2648 77 7 0 0.24 0.22 0 0 27 0.114 2.95 2.94 15 Pierce 1.6
(Shallow
phase)
Parkwood 118 361 0-7 7.80 100.0 18.85 4,159 720 622 0 0.22 0.99 16 1.0 63 0.177 9.43 1.99 31 Vero Seedy Gft. 24 P 12-8-42 1-26-43 1.5
f.s. loam 362 7-17 7.99 100.0 7.00 1,921 258 76 0 0.25 0.31 3 0.4 28 0.184 4.00 1.75 13 Beach 1.7
S (Shallow
phase)

Manatee 119 363 0-12 5.31 73.5 4.94 1,152116220 0.3 2.00 0.72 39 17.2 44 0.105 2.25 2.19 12 Vero Pineapple 25 G 4-19-42 5-20-42 2.0
f.s. loam 364 12-18 4.71 14.8 5.40 262 18 13 6.1 0.48 0.30 5 5.7 44.033 1.16 4.65 20 Beach 0. 1.9
Manatee 120 365 0-12 7.44 100.0 6.80 1,749 174 253 1.0 0.24 0.47 359 10.5 6 0.140 2.57 2.64 11 Mims Pineapple 2 P 5 10-46 10-3-46 1.6
loamy f.s. 366 12-26 8.15 100.0 4.90 1,292 176 351 0.9 0.27 0.33 93 3.4 3 0.020 0.92 5.83 27 0. 1.8
Manatee 121 367 0-7 6.42 56.2 8.90 1,400 881090.5 0.16 0.54 589 33.6 11 0.160 3.27 2.72 12 Mims Val. & 30 F 5-10-46 10-3-46 1.6
loamy f.s. 368 7-20 8.08 100.0 5.20 1,655 81153 1.1 0.27 0.29 7 6.5 9 0.030 0.99 5.26 19 P.A. 0. 1.8
369 20-34 8.32 100.0 5.40 1,69 116 11 .8 0.18 0.29 4 0.4 6 0.010 0.52 10.40 30 1.8
Manatee 122 370 0-10 7.69 100.0 14.56 3,8951940 242 0.1 0.29 0.30 99 0.8 10 0.180 5.83 2.33 18 Vero Marsh 20 E 12-17-41 2-25-42 1.9
f.s. loam 371 10-30 8.30 100.0 5.76 1,482 422 28 0.3 0.47 0.27 1.4 0 0.039 1.52 3.78 22 Beach Git. 1.9
Manatee 123V 372 0-8 7.50 100.0 17.30 5,666 356 23 0.3 0.09 1.08 172 6.5 11 0.217 6.64 2.59 18 Ft. Virgin Soil ....... 2-27-42 1.8
f.s. loam 373 8-18 8.10 100.0 9.22 2,909 243 29 0.5 0.09 0.11 27 1.0 3 0.098 2.7 3.35 16 Pierce 1.8
Manatee 124 374 0-8 7.72 100.0 18.64 5,430315 54 0.3 0.24 0.16 10 3.1 230.3188.25 2.26 15 Ft. Valencia Set2 .. .... 2-27-42 1.6
f.s. loam 375 8-18 8.10 100.0 10.06 2,748270 61 0.2 008 0.10 0.9 12 0.156 2.39 4.21 9 Pierce O. mos. 1.6
Manatee 125V 376 0-7 6.42 88.0 20.72 5, 18 0 0.17 0.27 13 2.6 21 0.409 8.60 2.41 12 Ft. Virgin Soil .... .. ... 8-20-4 1.6
f.a. loam 377 7-16 8.00 100.0 8.58 3,102 101 0 0.24 0.22 0 13 0.066 2.13 4.03 19 Pierce1.9







TABLE 3.-CHEMICAL ANALYSES OF THE MAJOR CITRUS GROVE SOILS OF FLORIDA (1942-1946 SURVEY)-Continued.

d i Exchangeable Bases P


l b 4 Z



Manatee f.s. 126F 378 0-18 6.09 8.8 27.39 6,929 653 7 00.25 0.27 12 3.5 12 0.37 10.28 2.66 16 Ft. Previously 8-20-4 1.7
clay loam Pierce farmed
(Deep phase) __________ __ __ _

Bradenton 127 379 0-7 4.97 44.7 3.80 464 39 8.0 0.85 0.0 44 11.5 10 0.09 1.93 1.97 12 Mims Pineapple 35 F 6-18-46 10-3-46 1.7
f.s. loam 380 7-18 5.89 91.6 1.80 519 4 42 .8 0.29 0.30 52 6.8 5 0.01 0.40 4.50 23 0. 1.9
Bradenton 128 381 0-14 5.30 75.0 4.40 992 162 11 2 0.80 0.44 112 13.6 22 0.06 2.21 1.99 20 Vero Marsh 24 G 12-21-42 1-27-4 2.0
loamy f.s. 382 14-36 5.39 86.6 1.00 363 44 20 1.6 0.44 0.35 21 5.1 12 0.017 0.60 1.66 21 Beach Gft. 2.2
(Stained
layer phase)
SBradenton 129 383 0-4 6.65 91.8 5.70 1,440 187 61 2.1 0.51 0.87 1,293 12.8 6 0.130 2.47 2.30 11 Titus- Indian 60 P 6-2-46 10-4-46 1.7
P loamy f.s. 384 4-24 5.65 79.2 0.82 182 38 34 1.2 0.60 0.56 99 15.2 5 0.010 0.24 3.41 14 ville River O. 2.0

Bradenton 130 385 0-12 6.08 89.3 6.00 1,611 177 266 1.6 0.38 0.80 315 18.6 45 0.093 2.81 2.14 17 Vero Valencia 24 P 2-3-43 3-13-43 1.9
loamy f.s. 386 12-24 5.30 69.5 1.20 227 40 113 0.7 0.10 0.34 25 4.6 28 0.018 0.60 2.00 19 Beach 0. 2.1
(Stained
layer phase)
Bradenton 131 387 0-5 6.09 88.4 7.10 1,807 178 65 2.9 1.04 0.71 1,222 14.4 7 0.140 2.92 2.43 12 Titus- Indian 60 F 6-2-46 10-4-46 1.7
loamy f.s. 388 5-18 5.24 72.8 1.10 222 34 30 2.4 0.57 0.34 92 20.9 3 0.020 0.40 2.75 12 ville River O. 1.9
Bradenton 132 389 0-12 5.79 30.9 7.12 657 66 118 4.9 0.95 0.91 167 31.9 23 0.090 3.72 1.91 24 Merritts Marsh 20 E 11-12-41 4-15-42 1.9
f.s. loam 390 12-18 6.81 98.0 2.48 633 158 61 5.9 0.28 0.19 152 18.3 0 0.031 1.15 2.15 22 Island Gft. 1.9
391 18-24 9.20 100.0 10.74 3,635 276 40 0.3 0.57 0.26 304 3.4 4 0.033 4.41 2.43 77 1.9
Bradenton 133 392 0-12 5.16 71.5 7.40 1,606 194 352 1.6 1.60 0.72 182 32.0 19 0.061 2.87 2.58 27 Vero Valencia 12 F 2-6-43 4-8-43 2.0
f.s. loam 393 12-18 5.70 80.3 7.60 1,583 350 342 0.3 0.19 0.42 207 17.3 11 0.098 2.18 3.47 13 Beach 0. 1.9
39418-24 7.51 99.0 14.50 4,178 383 769 0 0.18 0.32 16 4.7 2 0.068 3.53 4.11 31 1.8
Bradenton 134 395 0-8 6.00 87.0 8.02 2,204 182 300 0 0.38 0.27 213 15.8 29 0.087 2.93 2.74 19 Vero Marsh 12 G 2-6-43 4-8-43 1.9
loamy f.s. 396 8-15 6.60 81.9 6.60 1,526 261 260 0.3 0.29 0.26 66 2.7 11 0.047 2.20 3.00 27 Beach Git. 1.9
397 15-18 6.29 81.4 14.50 3,373 418 396 0.2 0.09 0.29 32 2.5 6 0.061 3.18 4.56 30 1.8
Bradenton 135 398 0-8 4.39 52.5 11.00 1,618 136 1 3.1 0.43 0.31 100 1.3 71 0.11 4.45 2.22 22 Merritts Marsh 12 G 6-9-43 7-1-43 1.7
f.s. loam 399 8-20 .16 75.4 2.60 654 65 48 0 0.20 0.27 80 8.2 1 0.037 0.75 3.46 12 Island Gft. _2.0











TABLE 3.-CHEMICAL ANALYSES OF THE MAJOR-CITRUS GROVE SOILS OF FLORIDA (1942-1946 SuRVEY)-Continued.

Exchangeable Bases P






Bradenton 136 400 0-8 6.00 97.7 13.08 3,791226 374 8.2 0.26 0.48 231 10.4 28 3.154 3.98 3.29 15 Merritts Pineapple 20+- G 6-1-43 7-1-43 1.7
f.s. loam 401 8-11 6.56 98.7 13.84 4,044 272 348 0.7 0.17 0.31 44 35.7 70 0.062 2.23 6.21 21 Island O. 1.7
Bradenton 137 402 0-8 5.22 30.0 15.30 1,790 210 220 6.0 2.40 0.59 276 12.6 65 3.078 3.08 4.90 23 Vero Seedy Gft. 24 G 12-12-42 1-26-43 2.0
f.s. loam 403 8-16 5.80 84.5 6.40 1,598 300 154 0.5 0.30 0.28 104 2.2 30 0.068 2.42 2.64 21 Beach 2.0
40416-22 7.42 100.0 10.92 3,193 374254 0.3 0.09 0.36 14 2.9 2 3.079 4.49 2.43 33 1.8
Bradenton 188 405 0-14 6.71 98.0 24.04 7,038 9 1 0 0.45 0.39 61 3.6 56 3.427 9.60 2.50 13 Hypo- Valencia 17 P ? 9-14-42 1.5
loamy f.s. 406 14-20 6.75 79.1 6.68 1,974 28 0 0.6 0.76 0.34 11 1.6 10 0.099 2.01 3.30 12 luxo 0. 1.9

Leon f.s. 139 407 0-12 4.52 45.5 4.58 697 83 69 8.1 0.84 0.55 165 24.4 19 0.068 2.36 1.94 20 Vero Marsh 12 G 5-15-42 9-17-42 2.1
408 12-24 4.65 53.5 0.97 189 16 19 3.8 0.22 0.40 18 7.3 0 0.011 0.45 2.15 24 Beach Gft. 2.2
SLeon f.s. 140 409 0-12 4.60 85.0 4.66 1,444 86 41 2.3 4.00 1.60 48 15.2 13 0.053 2.35 1.98 26 Hypo- Valencia 14 F 5-16-42 7-4-42 2.0
41012-24 5.51 75.0 0.66 128 55 0 0.8 0.55 0.35 13 3.3 0 0.012 0.30 2.20 14 luxo 0. 2.2
41124-30 4.83 19.5 5.34 411 15 40 1.5 2.41 0.57 112 18.5 2 3.039 1.97 0.30 29 2.2
Leon f.s. 141 412 0-6 5.39 44.0 5.00 635 64 17 1.3 1.19 0.50 449 20.4 8 0.080 2.42 2.06 18 Mims Pineapple 18 G 6-12-46 10-2-46 1.7
413 6-26 5.15 29.5 1.20 12 8 6 0.7 0.28 0,26 11 4.8 9 0.002 0.35 3.43 101 0. 1.9
Leon f.s. 142 414 0-5 6.02 82.2 6.70 1,570 174 78 2.6 0.59 0.34 387 17.5 9 0.090 3.25 2.06 21 Mims Pineapple 18 F 6-12-46 10-2-46 1.7
415 5-27 5.51 64.7 1.20 260 27 14 0.9 0.30 0.27 13 5.2 8 0.004 0.46 2.61 66 0. 2.0
Leon f.s. 143 416 0-8 5.10 49.8 7.44 1,050 86 24T 2.5 1.44 0.53 57 36.4 0 3.155 5.29 1.40 20 Merritts Marsh 20 P 11-18-41 4-15-42 1.8
417 8-24 5.80 55.0 1.26 258 2 33 2.0 0.55 0.31 3 1.2 0 ).016 0.70 1.37 26 Island Gft. 2.2
418 24-28 8.00 94.5 12.38 4,651 26 134 0.1 0.33 0.30 11 5.3 2 ).049 4.10 1.73 48 2.2

Immokalee 144 419 0-5 5.81 85.0 3.30 850 85 45 2.0 0.81 0.76 991 13.3 12 0.100 1.20 2.75 7 Mims Indian 5-40 P-F -23-46 10-2-4 1.8
f.s. 420 5-18 5.35 50.0 0.62 80 21 18 0.6 0.30 0.28 16 5.2 5 0.005 0.30 2.06 35 River 0. 2.0
421 18-34 5.24 35.0 4.30 446 43 95 1.6 0.29 0.30 357 32.2 4 0.020 0.93 4.63 27 1.9
Immokalee 145 422 0-8 4.87 54.0 3.70 632 39 45 5.0 1.62 0.86 505 29.6 8 0.070 1.59 2.32 13 Mims Indian R. & 40 F 6-6-46 10-2-46 1.8
f.s. 423 8-26 5.00 32.8 1.10 116 11 18 1.6 0.90 0.82 6 3.2 4 3.010 0.32 3.44 18 P.A. 0. 2.0
424 26-30 4.52 10.8 11.10 330 13 81 1.3 0.26 0.27 402 30.6 4 0.040 3.14 3.53 45 1.7
Immokalee 146 425 0-10 5.00 79.5 4.40 1,206 70 22 6.0 0.28 0.56 289 12.2 22 0.109 2.31 1.47 12 Port Valencia 13 G 6-23-42 12-14-42 1.9
f.s. 426 10-24 4.90 69.3 1.28 346 15 2 1.4 0.2 0.63 87 11.5 8 0.023 0.55 2.32 14 Mayaca O. ____2.1







TABLE 3.-CHEMICAL ANALYSES OF THE MAJOR CITRUS GROVE SOILS OF FLORIDA (1942-1946 SURVEY)-Continued.

t Exchangeable Bases P
Q Z E- __ g ---> 4


2- a - -


Sunniland 147 427 0-10 5.02 61.3 2.12 410 42 42 0.9 0.57 0.53 161 25.6 12 0.057 1.93 1.09 20 Loxa- Val. & 17 F 2-9-42 5-8-42 1.9
loamy f.s. 428 10-18 5.00 85.0 1.40 495 16 9 1.1 0.33 0.44 26 11.5 21 0.016 0.60 2.33 22 hatchee P.A. 0. 2.2
(Stained
layer phase)
Sunniland 148 429 0-8 5.96 85.3 2.44 590 143 38 Tr 0.10 0.88 44 6.9 36 0.051 2.13 1.14 24 Loxa- Val. & 16 P 2-4-42 5-8-42 2.1
loamy f.s. 430 8-18 6.05 76.7 0.60 199 132 0 0.3 0.12 0.53 10 3.0 86 0.012 0.40 1.50 19 hatchee P.A. 0. 2.4
(Stained
layer phase)
Sunniland 149V 431 0-8 4.70 47.5 4.20 5641116 15 0.38 0.27 4 3.6 18 0.081 2.87 1.46 21 Vero Virgin Soil ... ... .... 6-17-43 1.9
loamy f.s. 432 8-18 5.72 84.5 1.40 308 56 5 0 0.17 0.37 14 0.4 5 0.014 0.60 2.33 25 Beach 1.7
(Stained 433 18-22 6.54 81.4 11.80 3,160 7 5 0.17 0.24 0.9 5 0.063 3.88 .04 36 1.7
Slayer phase) 434 223 7.85 100.0 19.30 6280412 25 0 0.18 0.2 6 0 0 0.0219 8.81 60 1.8
Sunniland 150V 435 0-12 5.90 87.0 15.42 4,442 229 27 0.5 0.18 0.32 2 0.4 32 0.200 4.20 3.67 12 Vero Virgin Soil .... ... ... 6-17-43 1.8
f.s. loam 436 12-24 7.70 100.0 12.34 4,378 194 6 0.9 0.29 0.30 3 0.4 440.060 2.20 5.60 21 Beach 1.9

Sunniland- 151 437 0-7 6.80 98.0 2.00 642 74 38 1.9 020 1.24 206 8.1 44 0.082 2.71 0.74 19 Loxa- Seedy Gft. 17 F 2-5-42 5-8-42 2.0
Charlotte 438 7-18 7.69 100.0 0.80 307 19 0 0.21 0.5 0 220.017 0.45 1.70 15 hatchee 2.1
loamy f.s.
complex

Broward f.s. 152 439 0-10 4.80 70.0 6.64 1,173 103 106 6.8 0. 0.87 564 17.7 10 0.238 6.21 1.07 15 Jupiter Seedy Gft. 40+ P 8-15-42 9-14-42 1.5
Sunniland 440 10-20 6.30 90.0 2.08 644 28 41 0.38 0.34 251 6.4 10 0.034 1.36 1.52 23 1.9
loamy f.s. 441 20-24 7.87 100.0 1.30 359 40 38 0.2 0.08 0.37 21 3.1 7 0.032 1.22 1.06 22 1.7
complex
Broward f.s.- 153 442 0-10 5.69 76.5 9.40 2,207 113 101 1.1 0.65 1.66 416 18.1 9 0.184 4.93 1.90 16 Jupiter Seedy Gft. 40+ P 7-15-42 9-14-42 1.7
Sunniland 443 10-18 6.18 90.0 6.32 2,000 73 88 0. 0.09 0.38 608 7.0 9 0.055 1.96 3.22 21 1.9
loamy f.s.
complex
(Stained
layer phase)

Bladen f.s. 154 444 0-12 4.89 62.3 7.38 1,315 16 296 1.0 1.04 0 0.98 167 1.6 0141 3.82 1.67 16 Vero Valenia 25 F 4-20-42 5-20-42 1.9
loam I 445 12-18 4.69 77.3 8.40 2,094 191 144 1.4 0.28 0.30130 1.0 84 0.068 2.23 3.76 19 Beach 0. { _____ | _- I I1.9









TABLE 3.--CHEMICAL ANALYSES OF THE MAJOR CITRUS GROVE SOILS OF FLORIDA (1942-1946 SURVEY)- Continued.

SI Exchangeable Bases P


0 a aa
N____ _____ t

Bladen f.s. 5 446 0-12 4.50 55. 10.42 78657 107 14.4 1.35 0.65 102 7.4 0.140 3.18 3.28 13 Ft. Valencia 14 E 5-142 9-1-42 1.8
loam 447112-18 4.41 74.6 7.24 1,708271 37 5.6 0.50 0.52 0 0.7 1 0.035 .86 8.42 14 Pierce O. 2.0

Felda loamy 156V 448 0-7 5.95 90.0 2.20 758 20 44 0.6 0.21 0.29 4 0.7 6 0.044 0.90 2.44 12 Vero Virgin Soil ... 10-28-43 2.1
f.s. 449 7-20 6.39 90.0 1.28 471 37 62 0.5 0.22 0.1 0.1 110.01 0.35 3.66 14 Beach 2.2
450 20- 7.11 100.0 7.14 2,757 130 30 0. 0.32 0.21 4 0.2 15 0.012 1.52 4.69 73 2.1
Felda loamy 157 451 0-18 5.40 70.0 2.74 462 168 64 1.1 0.20 0.44 19 .2 20 0.094 2.47 1.11 15 Ft. Pope O. 2 G 5-20-42 5-22-42 2.0
f.s. 452 18-24 6.19 80.0 6.36 1,909 130 0.6 0.10 0.29 0 6 0.00 0.90 7.06 17 Pierce 2.1
Felda f.s. 158 453 0-7 4.80 77.5 3.00 693 80 1.6 0.57 0.72 18 2.4 27 0.199 3.91 0.76 11 Vero Seedy Gft. 1 F 2-14-43 4-9-43 1.9
loam 454 7-18 5.57 78.9 3.80 1,126 82 5 0.2 0.42 0.55 2 0 25 0.033 0.94 4.04 16 Beach 2.1
- Felda f.s. 159 455 0-15 7.29 100.0 3.58 1,361 63 82 0.2 1.15 0.55 115 5.5 34 0.059 1.20 2.98 12 Ft. Valencia 17 P 2-20-42 5-22-42 2.1
loam 456 15-21 8.01 100.0 2.98 943 169 61 1.3 0.10 0.41 13 2.9 0 0.026 0.75 3.97 17 Pierce O. 2.1
Felda f.s. 160 457 0-20 4.69 35.0 3.76 328 296 132 2.7 0.30 0.52 44 4.4 380.132 2.74 1.37 12 Ft. Valencia 5 E 5-21-2 2--22-42 2.0
loam 458 20-30 6.40 96.2 8.00 2,700 226 0 0.6 0.10 0.32 2 1.0 0 0.047 1.16 6.89 14 Pierce O. 2.0
Felda f.s. 161 459 0-15 6.89 76.3 4.58 1,395 57 125 2.0 0.55 0.57 108 3.7 7 0.054 3.66 1.25 39 Ft. Valencia 17 F 2-20-42 5-22-42 2.2
loam 460 15-21 8.10 100.0 2.20 794 44 32 1.7 0.10 0.36 3.0 0 0.029 0.60 3.66 12 Pierce 0. 2.0
Felda loamy 62 461 0-12 6.00 92. 4.76 1,556 91 118 5.6 0.70 0.96 158 9.7 00.084 1.88 2.42 13 Vero Marsh 15 G 1-20-41 2-26-42 2.0
f.s. 462 12-30 7.71 100.0 3.20 1,074101 76 5.0 0.30 0.27 67 8.4 0 0.038 0.75 4.26 12 Beach Gft. 2.0
Felda loamy 163 463 0-18 4.70 60.0 4.84 958 79 44 2.4 0.57 1.14 16 0.8 4 0.129 2.36 2.05 10 Ft. M.G.F. 3 G 2-4-42 2-27-42 1.9
f.s. 46418-36 6.27 93.4 3.96 1,262 87 9 0.9 0.48 0.80 1 0.5 2 0.043 1.10 3.60 14 Pierce 1.9
Felda f.s. 164 465 0-10 6.40 98.0 5.20 1,610 228 114 4.8 0.60 0.84 454 8.6 8 0.112 4.70 0.27 24 Vero Marsh 12 F 5-7-42 6-1-42 2.0
loam 466 10-18 5.49 79.0 2.40 577 97 84 1. 0.73 0.42 34 11.5 23 0.035 0.70 3.41 12 Beach Gft. 2.1
Felda loamy 165 467 0-12 4.52 28.1 5.34 489 92 8 1.4 0.95 0.62 34 4.6 25 0.097 2.01 0.93 12 Vero Valencia 15 F 9-6-41 5-25-42 2.1
f.s. 468 12-18 4.70 45.3 3.62 577 65 10 1.9 0.21 1.46 10 3.8 440.048 1.10 3.29 22 Beach 0. 2.1
Felda loamy 166 469 0-7 6.12 90.0 6.20 1,459 357 146 1.8 0.19 0.61 158 16.6 0 0.096 2.45 2.89 15 Vero P.A. & Val. 14 F 11-16-41 2-26-42 1.9
f.s. 470 7-12 6.39 87.6 4.56 823404 65 1.2 0.28 0.30 8 2.8 80.031 0.80 5.70 15 Beach O. 1.9
Felda f.s. 167 471 0-18 5.32 83.0 6.22 1,842 118 52 9.7 0.80 0.76 38 5.8 8 0.080 1.99 3.13 14 Ft. Ruby Gft. 2 G 4-22-41 2-28-42 2.0
loam 472 18-24 5.60 79.0 7.10 1,608 379 22 5.9 0.50 0.44 1 0.9 0 0.0300.81 8.76 15 Pierce 2.0







TABLE 3.-CHEMICAL ANALYSES OF THE MAJOR CITRUS GROVE SOILS OF FLORIDA (1942-1946 SuRVEY)-Continued.

Exchangeable Bases P a wC
6 1
z U U a os a
"0 02 P" P C8 P


Felda loamy 168 47 0-12 4.95 9.8 6.28 872 95 38 2.2 1.05 0.42 5 6 1 0.118 2.45 0.77 12 Vero Valencia 15 P 9-6-41 5-25-42 2.1
f.s. 474 12-18 5.05 60.5 4.46 983 9 0 15 031 038 15 2.7 0 0.063 145 3.08 1 Beach 2.1
Felda loamy 169 475 0-7 6.20 96.0 10.30 2,607 642 230 1.4 0.10 0.49 167 5.3 10 0.120 3.30 3.10 16 Vero P.A. & Val. 14 11-10-41 2-26-42 1.9
f.s. 476 7-12 5.73 82.3 7.08 1,326523 55 3.6 0.76 0.27 15 1.9 0 0.046 0.96 7.39 12 Beach O. 1.9

Felda f.s. 170 477 0-5 5.18 85.0 2.0 666 18 44 4.0 0.63 0.59 81 21.8 6 0.052 1.33 1.52 15 Ft. Valencia 5 P 6-13-42 9-16-42 2.1
loam-Char- 478 5-18 5.01 29.8 1.4 143 17 23 0. 0.46 0. 029 0.55 2.44 11 Pierce 0. 2.3
lotte loamy
f.s. complex
Felda f.s. 171 479 0-5 5.46 25.1 2.02 174 9 25 2.5 1.57 .27 8 1.3 7 0.08 1.33 1.52 13 t. Marsh 7 P 6-?-40 9-16-42 2.1
loam-Char- 480 5-12 5.30 70.0 1.20 36 16 14 0.6 1.10 2.06 123 8.5 5 0.030 0.65 1.84 13 Pierce Gft. 2.2
lotte loamy
f.s. complex _________ ______ ___

Charlotte 172F 481 0-10 5.00 54. 0.88 189 12 5 0.3 1.50 0.48 56 9.0 2 0.041 0.73 1.20 10 Vero Previously 9-17-42 2.2
f.s. 482 10-20 5.39 71.8 0.30 90 6 0 0.3 0.57 0.46 33 1.9 1 0.014 0.05 6.00 21 Beach farmed 2.3
483 20-30 5.55 31.0 1.00 143 0 0 0.2 0.46 0.51 11 8.7 2 0.003 0.10 10.00 19 2.3
Charlotte 173V 484 0-6 5.89 58.4 0.96 198 14 7 0.7 0.35 0.41 4 0.9 0 0.027 0.72 1.39 16 Vero Virgin Soil .... .... .... 2-25-42 2.3
loamy f.s. 485 6-18 7.31 100.0 0.20 67 14 0 0.11 0.26 1 0 0 0.006 0.15 7.50 15 Beach 2.3
Charlotte 174 486 0-8 6.81 98.0 1.22 370 96 16 0.6 0.33 0.44 38 1.4 0 0.030 0.77 1.58 15 Vero Navel 0. 1 F 9-27-41 2-25-42 2.2
loamy f.s. 487 8-20 8.15 100.0 0.22 84 0 0.6 0.33 0.44 2 0 0 0.005 0.15 1.46 17 Beach 2.2
Charlotte 175 4 0-6 5.99 51.4 2.82 496 4 2.4 1.20 0.59 688 15.6 11 0.092 1.90 1.48 12 Hypo- Seedy Gft. 40 F 5-14-42 7-4-42 2.0
f.s. 489 6-20 6.40 74.2 0.66 110 6 0 0 .22 0.40 17 1.8 0 0.005 0.20 3.30 23 luxo 2.2
490 20-24 4.75 35.0 1.78 273 0.7 0.22 0.35 53 7.7 2 J.014 0.60 2.97 25 2.2

Charlotte- 176V 491 0-8 5.50 40.2 1.62 222 29 0.33 0.22 9 0.2 6 0.054 1.0 1.54 11 Vero Virgin Soil .... .... .... 2-1-44 2.2
Arzell f.s. 492 8-18 5.95 56.1 0.88 207 13 0.3 0.22 0.14 2 0.1 0 0.029 0.65 1.35 13 Beach 2.2
complex
Charlotte- 177F 493 0-8 5.10 29.8 2.00 216 15 40 1.4 0.66 0.31 64 3.5 5 0.060 1.30 1.54 13 Vero Previously 2-2-44 2.2
Arzell f.s. 49 8-20 5.50 26. 0.70 71 11 0.5 0.46 0.23 7 0.5 0 0.011 0.20 3.50 11 Beach farmed 2.3
complex 49520-26 6.22 69. 0.50 166 0 0.48 0.27 2 0.1 5 0.005 0.20 2.50 23 2.4











TABLE 3.-CHEMICAL ANALYSES OF THE MAJOR CITRUS GROVE SOILS OF FLORIDA (1942-1946 SURVEY)--Continued.

Exchangeable Bases P

"a a & 3




Arzell f.s. 178 496 0-12 6.03 94.3 0.86 299 38 21 1.9 0.46 1.60 59 4.2 0 0.053 0.50 1.72 6 Ft. Marsh 3 P 1-13-42 2-27-42 2.8
497 12-18 5.60 92.2 8.35 3,149 51 2.5 0.69 0.41 4 0 0.012 0.50 8.18 24 Pierce Gft. 2.3
Arzell loamy 179 498 0-10 6.66 95.0 1.14 420 3 0 0.7 0.11 0.65 239 5.4 6 0.029 0.50 2.06 11 Loxa- Valencia 17 P 2-8-42 7-20-42 2.2
f.s. 499 10-20 6.78 98.0 0.60 220 24 0 0.4 0.22 0.40 39 4.0 2 0.073 0.10 6.00 8 hatchee O. 2.2
Arzell f.s. 180 500 0-1 5.32 75.0 1.20 296 36 55 1.1 0.84 1.01 244 16. 27 0.049 1.15 1.04 14 Ver Valencia 8 F 12-5-41 5-21-42 2.1
50115-24 5.60 60.0 0.80 191 14 10 2.1 0.23 0.37 55 2.4 18 0.023 0.45 1.77 11 Beach 0. 2.3
Arzell f.s. 181 502 0-15 5.44 21.2 3.48 202 44 41 1.0 0.60 0.52 214 14.2 8 0.055 1.22 2.85 13 Vero Valencia 8 F 12-5-41 5-21-42 2.0
035-2 .42 25.0 1.20 121 10 0 0.8 0.33 0.4 18 1.6 31 0.015 0.40 3.00 15 Beach 0. 2.2

SDelray loamy 182 504 0-30 5.17 67.6 8.94 2,008 9278 5.9 0.48 0.30 131 11.0 0 0.081 3.54 2.52 25 Vero Marsh 11 G 5-8-42 9-18-42 1.9
0 f.s. 505 30-36 6.00 21.8 6.86 480 19 171 0.3 0.40 0.44 14 1.7 0 0.039 1.21 5.67 18 Beach Gft. 2.0
Delray loamy 183 506 0-24 4.90 54.8 9.25 1,584 183 272 2.1 6.00 0.30 38 1.8 0 0.081 .89 2.72 24 Vero Valencia 19 E 1-15-42 2-26-42 2.0
s. 507 24-0 6.08 87.6 10.24 3,116 280 44 0.3 0.20 0.36 2 0 0 0.029 1.33 7.69 26 Beach 0. 2.0
Delray loamy 184 508 0-18 5.88 86.3 10.32 2,631 382 272 1.1 0.38 0.27 182 4.9 8 0.136 3.86 2.67 16 Vero Marsh 10 G 1-7-42 2-25-42 1.9
f.s. 509 18-30 5.68 84.1 7.02 1,69701 131 0.6 0.38 0.3 2 0 0 0.056 2.02 3.48 19 Beach Gft. 1.9

Davie f.s. 185 510 0-12 5.01 63. 11.88 2,295 149 49 2.0 0.42 0.48 299 11. 10.220 4.72 2.51 12 Port Valencia 13 E 6-10-42 12-14-42 1.7
(Stained 511 12-24 5.79 88.3 1.02 319 35 5 0 0.31 0.29 18 2.2 8 0.018 0.45 2.29 14 Mayaca 0. 2.1
layer phase)
Davie mucky 186 512 0-12 4.23 56.5 15.55 1,069 94 28 0.4 4.20 0.82 52 5.8 42 1.890 82.90 0.19 25 Davie L.G.G. 0. 14 G 4-7-42 4-28-42 0.7
f.s. 513 12-24 8.12 100.0 4.54 1,814 52 19 1.0 0.21 0.21 3 2. 0 0.094 2.36 1.92 14 2.1
Davie mucky 187 514 0-12 5.62 73.5 15.92 3,306 114 8 0.4 0.15 0.27 12 1.3 2 0.520 10.50 1.51 12 Davie L.G.G. 0. 1 G 1-1-42 6-22-42 1.5
f.s. 515 12-18 6.20 90.0 2.74 853 27 0 0.4 0.09 0.29 2 1.0 63 0.114 2.42 1.13 12 1.8
Davie mucky 188 516 0-12 5.48 74.0 16.65 1,620203 62 0.1 0.48 0.41 80 4.0 62 2.160 77.51 0.21 21 Davie Valencia 15 F 1-11-42 5-4-42 0.8
f.s. 517 12-18 7.70 100.0 6.80 2,606 88 17 2.4 0.10 0.52 1 0 57 0.272 4.49 1.51 10 0. 2.0
518 18-24 7.81 100.0 3.32 1,426 23 0 0.8 0.22 0.48 14 2.4 6 0.018 0.45 7.38 14 2.2
Davie mucky 189 519 0-24 4.35 47.1 17.05 1,261 1711123 6.3 0.50 0.40 90 36.0 47 1.850 63.57 0.27 20 Davie L.G.G. 0. 13 G 4-15-42 4-30-42 1.0
f.s. 520 24-30 6.99 96.0 1.98 761 41 15 1.4 0.22 0.24 25 8.6 13 0.032 0.85 2.32 15 ______2.2








TABLE 3.-CHEMICAL ANALYSES OF THE MAJOR CITRUS GROVE SOILS OF FLORIDA (1942-1946 SURVEY)-Continued.

Exchangeable Basee P


A a 440



Davie mucky 190 521 0-12 4.10 48.0 17.10 1,42712602 9.1 7.70 1.01 81 39.6 32.310 60.90 0.28 1 Davie L.G.. 0. 13 G 4-142 -1-42 1.1
f.s. 522 12-24 5.44 78.0 2.26 678 22 52 3.4 0.42 0.46 34 10.6 56 0.045 0.80 2.81 10 2.1
Davie mucky 191 23 0-12 5.26 74.0 20.50 2,715 299268 1.6 1.32 2.12 89 6.9 74 2.340 78.41 0.26 19 Davie Valencia 15 F 1-11-42 5-4-42 1.1
f.. 52412-18 7.90 100. 4.80 1,808 3 6 5.0 0.10 0.44 1 0 55 0.191 .0 0.96 15 0. 2.0
525 18-24 7.90 100.0 0.98 409 13 0 1.0 0.22 0.40 1 3.7 23 0.021 0.66 1.48 18 2.2
Davie mucky 192 526 0-8 6.21 56.7 22.38 4,736 198 72 1.8 0.20 0.40 16 0.7 130 0.007 10.72 2.09 89 Davie Navel 0. 1 F 4-28-43 5-9-43 2.0
f.s. 527 8-18 7.10 100.0 0.64 265 2 0 0.32 0.55 4 0.7 28 0.009 0.20 3.20 13 2.1
Davie mucky 193 528 0-12 7.55 100.0 25.7 6,11569 0 0 0.06 0.29 27 3.9 45 1.120 30.63 0.84 16 Davie L.G.G. 0. 4 F 1-26-42 5-2-42 1.3
00 f.s. 529 12-22 7.70 100.0 7.26 2,806152 0 0.10 0.34 3 1.8 52 0.103 2.77 2.62 16 2.1

Davie mucky 194 530 0-12 4.50 38.4 27.10 1,801 105 202 6. 8.00 0.66 60 14.0 93 1.280 46.88 0.58 21 Davie L.G.G. 0. 13 G 4-13-42 5-1-42 1.0
f.s. 531 12-30 5.65 84.0 1.84 590 20 23 2.3 0.32 0.59 2.8 60 0.040 1.00 1.84 14 2.1
Davie mucky 195 532 0-8 4.80 44.0 27.45 2,104 151 119 1.9 0.30 0.28 40 11.7 38 1.060 38.75 0.71 21 Davie Valencia 13 G 4-13-42 5-5-42 1.0
f.s. 533 8-24 5.30 70.0 1.44 414 15 5 1.4 0.11 0.44 3 0 560.025 0.65 2.37 15 0. 2.2
Davie mucky 196 4 0-24 5.00 56.5 29.30 4,168 26 147 6. 2.60 0.44 96 11.7 54 1.010 32.49 0.90 19 Davie Hamlin 0. 14 P 4-12-42 4-27-42 1.3
f.s. 535 24-36 6.52 78.5 7.32 1,919 156 19 2.7 0.19 0.19 30 2.9 00.096 7.92 0.92 48 1.9
Davie mucky 197 536 0-12 4.12 15.3 30.05 984 7119 3.0 19.50 0.80 4.4 840.78022.0 1.34 16 Davie L.G.G. 0. 13 F 4-13-42 5-1-42 1.3
f.. 537 12-24 5.22 65.8 1.28 330 14 31 3.5 1.10 0.70 1 0 60.026 0.70 1.82 16 2.2
Davie mucky 198V 538 0-10 5.30 63.0 30.45 3,100223 0 0.5 0.05 0.20 14 3. 20 1.650 0.00 1.01 11 Davie Virgin Soil .... .... .... 5-5-42 0.9
f.s. 539 10-24 5.78 85.3 3.42 1,157 35 0 0 0.10 0.59 0 0 12 0.045 1.35 2.563 17 2.1
Davie mucky 199 540 0-18 5.22 71.3 30.55 3,113 213 84 0.6 1.12 0.54 39 7.5 66 2.220 88.64 0.34 23 Davie L.G.G. 0. 8 G 4-3-42 4-25-42 0.8
f.s. 54118-24 8.10 100.0 3.36 1,233 61 160 0.5 0.21 0.21 8 1.9 80.092 2.26 1.49 14 2.1
Davie mucky 200 542 0-15 4.40 29.0 30.70 886 91 74 4.3 12.00 0.59 5819.1 25 2.500 77.16 0.39 18 Davie L.G.G. 0. 13 G 4-6-42 4-26-42 0.6
f.s. 543 15-24 7.90 100. 3.40 1,348 50 10 0.7 0.63 1.34 16 2.6 0 0.064 1.56 2.11 14 2.1
Davie mucky 201 544 0-12 4.00 15.8 3215 1,08 73 132 0.7 21.00 2.12 26 5.4 401.290 32.18 0.99 14 Davie L.G.. 0. 13 F 4-13-42 5-1-42 1.2
f.s. 545 12-20 6.80 98.0 1.90 716 29 31 2.1 0.53 0.80 1 0 580.04 1.05 1.81 13 _2.1











TABLE 3.-CHEMICAL ANALYSES OF THE MAJOR CITRUS GROVE SOILS OF FLORIDA (1942-1946 SuRVEY)--Continued.

Exchangeable Bases P

S0 o B --- o 0 V ^

co 0 U2 a A A U za 0ttAg

Davie mucky 202 546 0-12 6.60 92.8 35.00 7,133 391 61 0. 0.14 0.17 35 2.8 46 1.800 47.21 0.74 15 Davie Misc. Set 1 3-20-42 4-30-42 1.2
f.s. 547 12-18 7.19 100.0 5.92 2,398 55 8 00.10 0.21 2 0 27 0.101 2.41 2.45 14 mo. 2.1
(Burned)
Davie mucky 203 548 0-12 4.58 40.2 36.60 2,018 162138 3.8 1.12 0.54 36 9.6 40 2.250 60.33 0.61 16 Davie L.G.G. 0. 13 G 4-13-42 5-1-42 0.8
f.s. 549 12-30 6.65 96.0 2.68 1,039 30 15 1.3 0.32 0.42 17 2.0 28 0.045 1.50 178 19 2.1
Davie mucky 204 550 0-6 7.49 82.8 39.55 8,096 660 54 0 0.14 0.36 17 2.0 73 0.888 26.04 1.52 17 Davie L.G.G. 0. 1 F 9-1-42 1-23-43 1.4
f.s. 551 6-12 7.80 100.0 3.60 1,424 56 0 0 0.32 0.38 31 3.6 18 0.089 1.50 2.40 10 2.1
(Burned)
Davie mucky 205 552 0-12 4.72 50.4 45.60 4,406135 16 3.8 0.70 0.30 3 0 85 1.110 33.10 1.37 17 Davie L.G.G. 2 E 8-10-42 11-14-42 1.0
00 f.s. 553 12-18 5.80 85. 1.35 430 20 0 0.4 0.30 0.32 2 0 5 0.035 0.95 1.42 16 2.0
Davie mucky 206 554 0-12 4.24 40. 56.50 3,167 98 30 4.4 0.48 0.34 7 6.0 114 1.820 48.25 1.16 15 Davie L.G.G. 0. 2 G 8-10-42 11-14-42 0.8
f.s. 555 12-18 6.80 98.0 2.07 821 17 0 0.5 0.21 0.38 85 1.3 25 0.034 0.70 2.87 12 2.1
Davie mucky 207V 556 0-12 5.20 66.0 67.00 5.922 141 46 7.0 0.21 0.20 7 0.2 89 2.300 66.00 1.01 16 Davie Virgin Soil ... 3-28-46 0.7
f.s.
Davie mucky 208V 557 0-10 4.20 23.9 72.90 2,039 21 27 11.9 0.36 0.26 11 0.6 59 2.620 67.01 1.08 15 Davie Virgin Soil ... ... ... 4-11-43 0.6
f.s.
Davie mucky 209 558 0-14 6.31 78.5 78.80 10,735 213 111 1.3 0.40 0.53 14 0.8 106 2.530 68.00 1.15 16 Davie L.G.G. 0. 8 P 1-15-46 2-5-46 0.9
f.s. 559 14-20 7.78 100.0 3.20 1,044 22 10 0.3 0.26 0.27 8 0.4 65 0.130 3.20 1.00 14 1.7
Davie mucky 210 560 0-15 4.46 39.3 80.80 5,799 313 110 5.6 1.00 0.54 74 14.3 159 1.674 41.87 1.90 13 Davie L.G.G. 0. 3 G 2-2-43 4-12-43 1.0
f.s. 561 15-24 5.77 80.7 2.60 813 38 0 0.3 0.42 0.46 17 4.3 20 0.022 1.00 2.60 26 2.1
Davie mucky 211 620-14 6.28 74.3 86.60 11,235 192 90 1.7 .9 1.06 1 0.7 ND 2.650 72.50 1.19 17 Davie L.G.G. 0. 8 G 1-15-46 2-5-46 0.9
f.s. 56314-20 7.69 100.0 7.30 2,441 22 10 0.3 0.3 0.31 10 0.4 60 0.180 4.50 1.2 15 1.7
Davie mucky 212 64 0-18 5.90 35.4 95.55 4,11272 41 1.1 0.28 0.6 1 1.0 90 2.70 78.61 1.21 18 Davie L.G.G. 0. 2 E 2-1-43 4-12-48 0.7
f.s. 565 18-22 7.74 100.0 9.50 2,790 152 0 0.7 0.16 0.42 35 1.9 16 0.263 3.63 2.61 8 1.6
Davie mucky 213 66 0-8 5.40 31.5 100.80 5112 870 20 0 0.09 0.16 16 1.3 99 1.080 0.80 1.67 33 Davie L.G.G. O. 1 G 9-3-42 1-23-43 0.9
f.s. 567 8-12 5.75 87.2 29.60 667652 28 0 0.22 0.39 30 2.7 97 0.09514.83 1.99 90 _____ _1.5












TABLE 3.-CHEMICAL ANALYSES OF THE MAJOR CITRUS GROVE SOILS OF FLORIDA (1942-1946 SURVEY)-Concluded.








Everglades 214 568 0-3 4.80 42.0 77.5 3 341 70 4.2 0.3 0.35 38 14.9 173 2.200 69.73 1.12 18 Port Valencia 8 E -16-42 11-17-42 0.6
low phase)t I

Hialeah 215 570 0-14 7.32 83.6 38.25 7,608 428 60 1.6 0.26 0.47 3 1.9 11 1.070 2.74 1.50 14 Davie Seedy Gft. 5 E 4-20-42 6-23-42 1.3
mucky mar 571 14-18 7.650 42.9 3.54 550 26 12 0.5 0.10 0.32 2 0.6 0 0.075 1.20 2.95 9 2.0
. (Tentative
a name)
0 i 0. 0 0. 0 .. 2, o

e 2r 56 4.0 42. 7 526 4172 0.3 3 14.9 17320 .73 1.12 918 Port Va2encia 8 E 6.






Hialeah 216 572 0-1 7.18 46.4 76.50 8,014 288 4 0.3 0.06 0.31 3 113 2.190 8.12 1.31 15 Davie L.G.G . F 5-31-42 6-22-42 1.2
mucky marl 573 12-18 7.57 100.0 16.5 5,36 6 1 0. 0.09 0. 7 17 0.397 10.18 1.62 15 1.8
(Tentative
name)

Ochopee 217V 574 0-4 7.60 100.0 12.22 3,873 167 44 0.3 0.25 0.34 11 0 43 0.036 5.78 2.11 93 Vero Virgin Soil ... .. 6-17-43 1.7
marl 575 4-18 8.00 100.0 3.00 977 22 0.1 0.25 0.47 2 0.3 6 0.020 2.10 1.43 61 Beach _1.7

Rockdale 218 576 0-6 8.02 100.0 38.80 6,17 446 167 0 0.36 0.53 32 0.7 494 1.840 39.10 0.99 17 Key Key Lime 7 F 2-1-45 1-10-46 0.9
loamy sand Largo
Rockdale 219 577 0-6 7.89 96.0 43.80 5,340 308 72 0 0.21 0.45 37 0.8 121 0.032 48.20 0.91 87 Key Key Lime ? F 2-4-45 1-10-46 0.7
loamy sand Largo
Rockdale 220 578 0-6 8.05 82.0 56.85 6,191 318 75 0 0.21 0.56 48 1.4 73 0.160 6.40 1.01 204 Key Key Lime ? F 2 1-45 1-10-46 0.7
loamy sand Largo












TABLE 4.-MINIMUM, MAXIMUM AND AVERAGE AMOUNTS OF VARIOUS CONSTITUENTS FOUND IN DIFFERENT CITRUS GROVE
SOILS (1942-1946 SURVEY).
IPounds per Acre-Six-Inches of Soil ___
Soil No. Base Exch. I Ni- Total Organic Ratio
Series of Depth pH Satu- Cap. ____ ExchangeableBases____ __ P Ni- N Matter g tE C Ratio
Sam- ration m.e./ I-- Acid Water trate % % % O.M. C:N
ples __ 100 g. Ca Mg K Mn Zn Cu Sol. Sol. N ___ _
S I I I
Min. 5.11 48.8 2.50 515 30 61 3.5 4.75 0.80 369 18.0 5 0.050 1.31 1.91 12
3 Surface Max. 5.89 82.2 6.70 1,668 41 101 8.4 12.42 3.19 706 28.8 23 0.121 2.47 2.71 15
Norfolk __ Soil Aver. 5.39* 67.0 4.20 950 36 83 5.7 8.26 1.86 531 21.9 11 0.080 1.83 2.21 14
Min. 4.77 27.8 1.40 137 20 32 0.6 0.20 0.34 134 9.0 4 0.010 0.45 3.04 19
3 Subsoil Max. 5.99 56.7 2.30 386 60 75 1.4 1.05 0.44 496 22.8 14 0.014 0.49 5.11 28
Aver. 5.39 43.0 1.80 235 36 47 1.0 0.58 0.39 266 14.5 8 0.011 0.47 3.94 25

1 I Surface __ 6.60 92.0 3.02 1,041 101 17 11. 1 0.33 1.22 242 9.0 15 0.020 1.55 1.94 45
SBlanton ubsoi 6.95 9 0.84 3041 4 3 0.5 0.35 0.31 48 2.8 8 0.010 0.25 3.36 15

Min. 4.85 20.4 2.00 209 10 27 0.3 0.31 0.49 212 6.5 14 0.030 0.95 1.87 8
4 Surface Max. 6.31 94.3 3.80 888 42 84 6.8 2.10 2.96 517 19.2 18 0.118 2.03 2.45 20
Lakewood Soil Aver. 5.49 56.1 2.91 522 27 61 2.7 0.82 1.19 328 14.2 16 0.061 1.40 2.15 16
Min. 4.95 24.5 0.54 35 0 5 0 0.21 0.32 42 1.1 0 0.009 0.25 1.80 12
4 Subsoil Max. 6.15 88.7 1.94 247 60 61 1.1 0.40 0.55 180 8.8 10 0.021 1.00 2.48 34
Aver. 5.50 53.3 1.24 168 18 29 0.6 0.31 0.40 108 4.5 6 0.014 0.61 2.09 23

Min. 7.12 84.6 5.02 1,636 132 281 0 0.21 1.01 587 23.0 61 0.093 2.26 2.22 13
2 Surface Max. 7.39 94.0 6.54 1,865 143 418 0.2 0.22 1.05 1008 26.0 73 0.117 2.62 2.49 14
Cocoa Soil Aver. 7.26 89.3 5.78 1,751 138 350 0.1 0.22 1.03 798 24.5 67 0.105 2.44 2.36 14
(Tentative Min. 7.60 100.0 3.04 1,146 84 108 1.3 0.11 0.35 229 3.0 0 0.034 1.10 2.76 15
name) 2 Subsoil Max. 7.70 100.0 3.40 1,247 112 132 1.5 0.22 0.62 451 7.0 0 0.045 1.20 2.83 19
Aver. 7.65 100.0 3.22 1,197 98 120 1.4 0.17 0.49 340 5.0 0 0.040 1.15 2.80 17

*Arithmetical average of pH values rather than of actual hydrogen ion concentration.









TABLE 4.-MINIMUM, MAXIMUM AND AVERAGE AMOUNTS OF VARIOUS CONSTITUENTS FOUND IN DIFFERENT CITRUS GROVE
SOILS (1942-1946 SURVEY)-Continued.


Soil No. Base Exch. Exchangeable Bases P Ni- Total Organic Ratio
Series of Deth p Satu- Cap. trate N Matter Ex Cap. Ratio
Sam- ration m.e./ Acid Water N % % :N
ples %_ 100 g. Ca Mg K Mn Zn Cu Ai Sol. Sol. ___ C:

Min. 5.30 60.0 5.40 1,384 91 88 0 0.09 0.34 7 0 9 0.105 2.29 1.38 8
13 Surface Max. 8.01 100.0 18.8 4,159 841 622 8.0 2.24 0.99 1215 41.6 63 0.357 9.43 2.65 1
Parkwood Soil Aver. 7.36 93.7 10.87 2,758 277 226 1.5 0.37 0.61 249 11.8 22 0.206 5.03 2.19 15
in. 7.7 37.1 2.80 644 12 13 0 0.08 0.17 0 0 0 0.008 .16 1.38 2
13 Subsoil ax. 8.30 100.0 8.02 2,33 460 201 1.2 0.90 0.59 184 25.2 50 0.184 4.00 33.72 17
Aver. 8.02 95.0 5.11 1,393 133 103 0.4 0.30 0.35 28 3.7 13 0.077 1.82 5.53 13


Min. 5.31 66.2 4.94 1,152 88 54 0.1 0.16 0.16 99 0.8 6 0.105 2.25 2.19 11
5 Surface Max. 7.72 100.0 18.64 5,430 940 253 1.0 2.00 0.72 589 33.6 44 0.318 8.25 2.72 18
00 Manatee Soil Aver. 6.92 85.9 10.77 2,725 327 176 0.4 0.59 0.44 309 13.0 19 0.181 4.43 2.43 14
Min. 4.71 14.8 4.90 262 18 13 0.2 0.08 0.10 i 6 0 0 0.020 0.92 3.78 9
5 Subsoil Max. 8.30 100.0 10.06 2,748 422 351 6.1 0.48 0.33 93 6.5 44 0.156 2.39 5.33 27
Aver. 7.47 83.0 6.26 1,488 193 121 1.7 0.31 0.26 46 3.6 14 0.056 1.40 4.65 19


Mi. 4.39 30.0 3.80 464 9 31 0 0.26 0.27 44 1.3 6 0.061 1.93 1.91 11
12 Surface Max. 6.71 98.0 24.04 7,038 226 374 8.2 2.40 0.91 1293 32.0 71 0.427 9.60 4.90 27
Bradenton Soil Aver. 5.70 71.4 9.41 2,085 149 181 3.7 0.84 0.58 351 14.9 32 0.127 3.58 2.58 18
Min. 5.16 69.5 0.82 182 28 0 0 0.10 0.19 11 1.6 0 0.010 0.24 1.66 12
12 Subsoil Max. 6.81 98.7 13.84 4.044 350 348 5.9 0.76 0.56 207 35.7 70 0.305 2.42 6.21 27
Aver. 5.82 83.1 4.34 1,127 136 121 1.7 0.35 0.33 79 11.6 16 0.066 1.27 3.21 18


Min. 4.52 44.0 4.58 635 64 17 1.3 0.59 0.34 48 15.2 0 0.053 2.35 1.40 18
5 Surface Max. 6.02 85.0 7.44 1,570 174 247 8.1 4.00 1.60 449 36.4 19 0.155 5.29 206 26
Leon Soil Aver. 5.13 61.3 5.68 1,079 99 90 3.4 1.61 0.70 221 22.8 10 0.089 3.13 1.89 21
Min. 4.65 29.5 0.66 123 8 0 0.7 0.22 0.26 3 1.2 0 0.002 0.30 1.37 14
5 Subsoil Max. 580 7.0 1.26 260 55 33 3.8 0.55 0.40 18 7.3 9 0.016 0.70 3.43 101
Aver. 5.32 55.5 1.06 192 26 14 1.6 0.38 0.32 12 4.4 3 0.009 0.45 2.35 46










TABLE 4.-MINIMUM, MAXIMUM AND AVERAGE AMOUNTS OF VARIOUS CONSTITUENTS FOUND IN DIFFERENT CITRUS GROVE
SOILS (1942-1946 SuRVEY)--Continued.


Soil No. Base Exch. Exchangeable Bases P Ni- Total Organic Ratio
Series of Depth pH Satu- Cap. ____I trate N Matter Ex. Cap. Ratio
Sam- ration m.e./ I Acid Water N % % % O.M. C:N
pies % 100 g. Ca IMg K Mn Zn i Cu Sol. Sol. o

Min. 4.87 54.0 3.30 632 39 22 2.0 0.28 0.56 289 12.2 8 0.070 1.20 1.47 7
3 Surface Max. 5.81 85.0 4.40 1,205 85 45 6.0 1.62 0.86 991 29.6 22 0.109 2.31 2.75 13
Immokalee Soil Aver. 5.23 72.8 3.80 896 6 37 4.3 0.90 0.73 595 18.4 14 0.093 1.70 2.18 11
Min. 4.90 32.8 0.62 80 11 2 0.6 0.30 0.28 6 8.2 4 0.005 0.30 2.06 14
3 Subsoil Max. 5.35 69.3 1.28 46 21 18 1.6 0.90 0.63 87 11.5 8 0.023 0.55 3.44 35
Aver. 5.08 50.7 1.00 181 16 13 1.2 0.51 0.41 36 6.6 6 0.013 0.39 2.61 22


Min. 5.02 61.3 2.12 410 42 38 Tr. 0.10 0.53 44 6.9 12 0.051 1.93 1.09 20
2 Surface Max. 5.96 85.3 2.44 590 143 42 0.9 0.57 0.88 161 25.6 36 0.057 2.13 1.14 24
Sunniland __ Soil Aver. 5.49 73.3 2.28 50 92 40 0.4 0.33 0.70 102 16.2 24 0.054 2.03 1.11 22
Min. 5.00 76.7 0.60 199 16 0 0.3 0.12 0.44 10 3.0 21 0.012 0.40 1.50 19
0o 2 Subsoil Max. 6.05 85.0 1.40 495 132 9 1.1 0.33 0.53 26 11.5 86 0.016 0.60 2.33 22
m Aver. 5.52 80.8 1.00 347 74 4 0.7 0.22 0.48 18 7.2 53 0.014 0.50 1.91 20

Sunniland- I I
Charlotte 1 Surface 6.80 98.0 2.00 642 74 38 1.9 0.20 1.24 206 8.1 44 0.082 2.71 0.74 19
Complex 1 Subsoil 7.69 100.0 0.80 307 19 0 0 0.21 0.52 2 0 27 0.017 0.45 1.70 15


Min. 4.80 70.0 6.64 1,173 103 101 1.1 0.45 0.87 416 17.7 9 0.184 4.93 1.07 15
Broward- 2 Surface Max. 5.69 76.5 9.40 2,207 113 106 6.8 0.65 1.66 564 18.4 10 0.238 6.21 1.90 16
Sunniland __ Soil Aver. 5.25 73.3 8.02 1,69 108 104 4.0 0.55 1.27 490 18.1 10 0.211 5.57 1.49 16
Complex Min. 6.18 90.0 2.08 644 28 41 0.4 0.09 0.34 251 6.4 9 0.034 1.36 1.52 21
2 Subsoil Max. 6.30 90.0 6.32 2,001 73 88 0.5 0.38 0.38 608 7.0 10 0.055 1.96 3.22 23
Aver. 6.24 90.0 4.20 1,323 51 65 0.5 0.24 0.36 430 6.7 10 0.045 1.66 2.37 22


Min. 4.50 55.7 7.38 1,315 157 107 1.0 1.04 0.65 102 7.0 5 0.140 3.18 1.67 13
2 Surface Max. 4.89 62.3 10.42 1,786 165 296 14.4 1.35 0.98 167 11.0 30 0.141 3.82 3.28 16
Bladen Soil Aver. 4.70 59.0 8.90 1,551 161 202 7.7 1.20 0.82 135 9.0 18 0.141 3.50 2.48 15
Min. 4.41 74.6 7.24 1,708 191 37 1.4 0.28 0.30 0 0.7 1 0.035 0.86 3.76 14
2 Subsoil Max. 4.69 77.3 8.40 2,094 271 144 5.6 0.50 0.52 30 1.0 84 0.068 2.23 842 19
Aver. 4.55 76.0 7.82 1,901 231 91 3.5 0.39 0.41 15 0.9 43 0.052 1.55 6.09 17








TABLE 4.-MINIMUM, MAXIMUM AND AVERAGE AMOUNTS OF VARIOUS CONSTITUENTS FOUND IN DIFFERENT CITRUS GROVE
SoILs (1942-1946 SURVEY)-Continued.


Soil No. Base Exch. Exchangeable Bases P Ni- Total Organic Ratio
Series of Depth pH Satu- Cap. I trate N Matter C Ratio
Sam- ration mn.e./ I [Acid Water N % %O.M. :N
ples | % 100 g. Ca | Mg K Mn Zn Cu | Sol. | Sol.

Min. 4.52 28.1 2.74 328 57 8 0.2 0.10 0.42 16 0.8 0 0.054 1.20 0.27 10
13 Surface Max. 7.29 100.0 10.30 2,607 642 230 9.7 1.15 1.14 454 17.0 38 0.199 4.70 3.13 39
Felda Soil Aver. 5.64 72.8 5.14 1,202 183 95 2.8 0.59 0.66 106 5.6 15 0.106 2.70 1.77 16
Min. 4.7 4 45.3 2.20 577 44 0 0.2 0.10 0.27 0 0 0 0.026 0.60 3.08 12
13 Subsoil Max. 8.10 100.0 8.00 2,700 523 84 5.9 0.76 1.46 67 11.6 44 0.063 1.45 8.76 22
Aver. 6.25 83.2 4.59 1,208 184 32 2.0 0.34 0.48 15 3.0 8 0.038 0.92 5.01 15


Min. 5.18 25.1 2.00 174 9 25 2.5 0.63 0.59 581 15.3 6 0.052 1.33 1.52 13
Felda- 2 Surface Max. 5.46 85.0 2.02 666 18 44 4.0 1.57 3.27 638 21.8 7 0.058 1.33 1.52 15
oo Charlotte Soil Aver. 5.32 55.1 2.01 42 14 35 3.3 1.10 1.93 610 18.6 7 0.055 1.33 1.52 14
: Complex Min. 5.01 29.8 1.20 143 16 14 0.6 0.46 0.68 123 8.5 5 0.029 0.55 1.84 | 11
2 Subsoil Max. 5.30 70.0 1.34 336 17 23 0.8 1.10 2.06 147 9.4 6 0.030 0.65 2.44 13
Aver. 5.15 49.9 1.27 240 17 19 0.7 0.78 1.37 135 9.0 6 0.030 0.60 2.14 12


Min. 5.99 51.4 1.22 370 34 16 0.6 0.33 0.44 38 1.4 0 0.030 0.77 1.48 12
2 Surface Max. 6.81 98.0 2.82 496 96 50 2.4 1.20 0.59 688 15.6 11 0.092 1.90 1.58 15
Charlotte Soil Aver. 6.40 74.7 2.02 4331 65 33 1.5 0.76 0.51 363 8.5 5 0.061 1.33 1.53 13
in. 6.40 74.2 0.22 84 8 0 0.4 0.22 0.40 2 0 0 0.005 0.15 1.46 17
2 Subsoil Max. 8.15 100.0 0.66 11 64 0 0.6 0.33 0.44 17 1.8 0 0.005 0.20 3.30 23
Aver. 7.27 87.1 0.44 97 36 0 0.5 0.27 0.42 9 0.9 0 0.005 0.17 2.38 20


Min. 5.32 21.2 0.86 202 35 0 0.7 0.11 0.52 59 4.2 0 0.029 0.50 1.04 6
4 Surface Max. 6.66 95.0 3.48 420 44 55 1.9 0.84 1.60 244 16.0 38 0.055 1.22 2.85 14
Arzell __ Soil Aver. 5.86 71.4 1.67 304 38 29 1.2 0.50 0.95 189 10.0 18 0.047 0.86 1.92 11
vin. 5.42 25.0 0.60 1211 10 0 0.4 0.22 0.37 4 0 0 0.012 0.10 1.77 8
4 Subsoil Max. 6.78 08.0 8.35 3,149 239 51 2.5 0.69 0.41 55 4.0 31 0.073 0.50 8.18 24
Aver. 5.85 68.8 2.74 920 72 15 1.5 0.37 0.40 29 2.0 13 0.031 0.36 4.74 15











TABLE 4.-MINIMUM, MAXIMUM AND AVERAGE AMOUNTS OF VARIOUS CONSTITUENTS FOUND IN DIFFERENT CITRUS GROVE
SOILS (1942-1946 SURVEY)--Concluded.

Soil No. Base Exch. Exchangeable Bases P i Total Organic Ratio
Series of Depth pH Satu- Cap. rate N Matter x. Cap Ratio
Sam- ration m.e./ I Acid Water N % % % O.M. C :N
ples %__ 100 g. Ca Mg K Mn Zn Cu Sol. Sol.
Min. 4.90 4.8 8.94 1,584 91 272 1.1 0.38 0.27 38 1.8 0 0.081 3.39 2.52 16
3 Surface Max. 5.88 86.3 10.32 2,631 382 278 5.9 6.00 0.30 182 11.0 8 0.136 3.86 2.72 25
Delray Soil Aver. 5.32 69.6 9.50 2,07 219 274 3.0 2.29 0.29 117 5.9 3 0.099 3.60 2.64 22
Min. 5.68 21.8 6.86 480 19 44 0.3 0.20 0.84 2 0 0 0.029 1.21 3.48 18
3 Subsoil Max. 6.08 7. 10.24 3,116 01 173 0.6 0.40 0.44 14 1.7 0 0.056 2.02 7.69 26
Aver. 5.92 64.5 8.04 1,764 200 115 0.4 0.33 0.38 6 0.6 0 0.041 1.52 5.61 21

Mi. 4.00 1.3 11.88 886 71 0 0 0.06 0.16 3 0 2 0.007 4.72 026 12
26 Surface Max. 7.5 100.0 100.80 11,235 660 302 9.1 21.00 2.12 299 39.6 159 2.650 88.64 2.51 89
Davie Soil Aver. 5.22 55.0 39.46 ,868 225 98 2.6 3.26 0.61 48 8.5 64 1.574 49.81 1.00 21
Min. 5.22 65.8 0.64 264 2 0 0 0.09 0.19 1 0 0 0.009 0.20 0.92 8
0 26 Subsoil Max. 8.12 100.0 29.60 6,676 652 160 5.0 1.10 1.34 35 10.6 97 0.272 14.83 3.20 90
Aver. 6.82 92.2 4.63 1,474 72 20 1.2 0.30 0.43 13 2.1 34 0.087 2.64 1.99 18

Everglades 1 Surface 4.80 42.0 77.85 3,3251 341 70 4.2 0.36 0.35 1 38 15.0 173 2.200 69.73 1.12 18
1 Subsoil 5.38 66.4 10.58 2,027 134 18 1P.0 0.16 0.32 1 3 6.0 63 0.188 6.61 1 60 20
_ = __---- _-- 1 -_-_-- - -
Min. 7.18 46.4 38.25 7,608 288 44 0.3 0.06 0.31 3 1.9 11 1.070 25.74 1.31 14
2 Surface Max. 7.32 83.6 76.50 8014 428 60 1.6 0.26 0.47 3 1.9 113 2.190 58.12 1.50 15
Hialeah Soil Aver. 7.25 65.0 57.38 7,81 358 52 1.0 0.16 0.39 3 1.9 62 1.630 41.93 1.41 15
(Tentative Min. 7.50 42.9 3.54 550 26 0 0.5 0.09 0.29 2 0.6 0 0.075 1.20 1.62 9
name) 2 Subsoil Max. 7.57 100.0 16.55 7,608 365 12 1.6 0.10 0.32 2 0.7 17 0.397 10.18 2.95 15
Aver. 7.54 71.5 10.05 4,079 196 6 1.1 0.10 0.31 2 0.7 9 0.236 5.69 2.29 12

Min. 7.89 82.0 38.80 5,340 308 72 0 0.21 0.45 32 0.7 73 0.032 39.10 0.91 17
3 Surface Max. 8.05 100.0 56.85 6,191 446 167 0 0.36 0.56 48 1.4 494 1.340 56.40 1.01 204
Rockdale Soil Aver. 7.99 92.7 46.48 5,903 357 105 0 0.26 0.51 39 1.0 229 0.511 47.90 0.97 103





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