DEPARTMENT OF SOILS IITMEOGRAPH REPORT 63-5 HAY, 1963
ARREDONDO SOILS OF FLORIDA
L. G. Thompson, Jr., R. E. Caldiell,
R. G. Leighty and V. U. Carlisle
Department of Soils
Agriculture Experiment Station
University of Florida
Introduction ................ ....... .
General Characteristics of the Series ............... 1
Geology and Physiography ..... ......... ... . . 2
Climate .. . *. . . . . .. . . . 2
Official Series Description ....... ... . . 2
Description and Extent of Major Mapping Units . . . . . . .
Alachua County . . . . . . . . . *
Gadsden County ...... .. .. .... . . .
Hillsborough County . . . . . . . . . . 6
Suwannee County . . . . . . . . . 7
Physical, Chemical and Mineralogical Properties . . .. . . 7
Management of Arredondo Soils............. . . 8
Erosion Control . . . . . . . . . . 10
Irrigation 1. .. . . . . . 10
Rotations, Green Manure Crops and Poultry Manure .. .. . 1.
Microbial Activities . . . . . . . . . . . 1
Placement of Nutrients ..... . .. . .. 19
Retention and Levels of Boron . . . . . . . . 20
Fertility Experiments . . . . . . . . . . 21
Pastures . . .......... . . . 21
Corn . . . . . . . .. .. 24
Oats .. . . .. . . . . .. . 2
Lupine . . . . . . . . . . . . 25
Peanuts . . . . . . 26
Vegetables . . .. . . .** . . 26
Tung Trees .. . ........... . . . . 26
Literature Cited . . . . . . . . 28
General Characteristics of the Series
The Arredondo series consists of deep, well-drained, medium to strongly
acid soils. They have developed from deep beds of unconsolidated sands and
loamy sands which are mixed with phosphatic materials. They occur on level
to gently rolling uplands with a few small areas of steeper slope. These
soils have gray to dark grayish-brown surface layers from h to 8 inches
thick. They are underlain by yellowish-brown to brownish-yellow horizons
that extend to depths of more than l2 inches. The subsoil is underlain by
a mottled fine sandy loam to fine sandy clay loam. Arredondo soils are
associated with the Gainesville, Fellowship and Zuber soils. They have a
lighter colored subsoil than Gainesville soils and a thicker, coarser
textured subsoil than the Fellowship soils. In Arredondo soils the fine-
textured materials occur at depths of more than 30 inches, whereas they
are at depths of less than 30 inches in the Fellowship and Zuber soils.
In profile characteristics the Arredondo soils are similar to the Lakeland
soils but have a higher content of phosphorus. They are more brown than
the Lakeland, less brown than the Gainesville and much less gray than the
Fellowship soils. The native vegetation consists of longleaf and loblolly
pines, various oaks, hickory and native grasses. Arredondo soils have good
surface and internal drainage, a.low available moisture-holding capacity
and are somewhat drought. They are used mainly for corn, peanuts, small
grains, vegetables and pastures. The native fertility is usually low, but
where the slopes are gentle and good management is practiced, these soils
are moderately well-suited to general farm crops. They are well-suited to
woodland and improved pastures of deep rooted, drought-resistant bahia-
grass and similar grasses.
LOCATION OF MAJOR AREAS OF ARREDOIDO AND ASSOCIATED SOILS IN FLORIDA
Geology and Physiography
Arredondo soils have developed from the Hawthorn geological formation,
which consists of deep beds of unconsolidated loamy sands that are influ-
enced by phosphatic materials. These soils are associated with the Gaines-
ville, Fellowship and Fort Meade soils, all of which have a higher content
of phosphate than most other soils of Florida.
Arredondo soils occur in nearly level (0-2 percent) to undulating
(2-8 percent) areas, but some small areas have 8 to 20 percent slopes.
The climate of the Arredondo soil areas in Florida is characterized by
long, warm summers, short mild winters and high humidity. These conditions
are very favorable for growing most crops and trees common to the area.
The average annual temperature is 700 F., with maximums of about 900 F.
during the months of June to August and minimums near 350 F. in January
and February. Temperatures have gone as high as 1030 F., and as low as
60 F., but such extremes are rare.
The annual rainfall averages h9 inches, and is fairly well distrib-
uted (37). Somewhat larger amounts of precipitation usually occur in July
and August. An occasional short drought in late spring or in the fall may
cause damage to crops, grasses and trees.
OFFICIAL SERIES DESCRIPTION
The Arredondo series consists of sands and loamy sands that have Red-
Yellow Podzolic color profiles. These soils are derived from beds of uncon-
solidated sands and loamy sands, in places mixed with residuum from phosphatic
materials. The Arredondo soils commonly occur associated with the closely
related Gainesville, Fellowship, Fort Meade, Kanapaha, Hague and Zuber soils.
They have lighter-colored profiles than the Gainesville, are coarser textured
in the lower part than the Fellowship, are better drained than the Kanapaha,
and have lighter-colored surface horizons than the Fort Meade soils. The
Arredondo soils in the past included the Zuber soils which, along with the
Hague, are shallower (less than 30 inches) to fine-textured materials than
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the Arredondo soils. The Arredondo soils differ from the Lakeland series
in being affected by or overlying phosphatic limestone. They occupy a rel-
atively small acreage but have local agricultural importance.
Soil Profile: Arredondo loamy fine sand
Ap 0-6" Dark gray (10YR h/l) loamy fine sand, gray (10YR 5/1) when
dry; weak fine crumb structure or single grained; nearly
loose; boundary clear, smooth; strongly acid. 3 to 8 inches
A2 6-15" Light yellowish-brown (10YR 6/h) loamy fine sand, pale brown
(10YR 6/3) when dry; weak fine crumb structure; nearly loose;
boundary gradual and wavy; medium acid. 8 to lh inches thick.
B2 15-h0" Yellowish-brown (10YR 5/6) loamy fine sand, light yellowish-
brown (10YR 6/h) when dry; weak fine crumb structure; nearly
loose: boundary gradual and wavy; medium acid. 20 to 30
B3 h0-56" Brownish-yellow (10YR 6/6) loamy fine sand, pale brown (10YR 6/3)
when dry: weak fine crumb structure; nearly loose; boundary
gradual and irregular; medium acid, slightly acid in lower part.
10 to 20 inches thick.
D 56-76"+ Light gray (10YR 7/2) fine sandy loam to fine sandy clay loam,
very pale brown (10YR 8/3) when dry; distinct medium mottles
of white (10YR 8/1) are common; weak fine to medium subangu-
lar blocky structure; friable to firm; slightly acid to
Range in characteristics: Types include fine sand, loamy fine sand, sand,
and loamy sand. Average combined thickness of horizons above the D usually
ranges from about h2 to 72 inches. Where the total ranges from about 30
to h2 inches, a shallow phase is recognized, and where greater than 72
inches, a deep phase. The A2 and B2 horizons may range in color from yel-
lowish-brown to browmish-yellow (1CYR 6/6) or yellow (2.5Y 8/6). In places,
especially in the shallower spots, limestone fragments may be encountered
in the D horizon. Weathered phosphatic pebbles usually occur on the surface
and in the profile.
Topography: Level to strongly sloping.
Drainage: Well to somewhat excessively drained. Crops may suffer for lack
of moisture on the more sandy spots during dry seasons.
Vegetation: Slash, loblolly and longleaf pines, red, live, laurel and water
oaks, magnolia,.sueetgum, dogwood and hickory.
Use: Approximately 75 percent cleared and used for the production of pea-
nuts, corn, watermelons, oats, bright tobacco, sweet potatoes and pasture.
Distribution: Scattered in a fairly narrow belt from the eastern part of
Hillsborough County, Florida, north nearly to the Georgia line, A few small
areas may occur as far west as Tallahassee, Florida, and in Thomas, Brooks,
and Lowndes County, Georgia.
Type location: West part of Marion County, Florida.
Series established: Alachua County, Florida, 1942.
Soil Survey Soil Conservation Service
U. S. Department of Agriculture
DESCRIPTIONS AND EXTENT OF MAJOR MAPPING UNITS
Arredondo soils occur chiefly in the north central portion of the State
in Alachua and Marion counties. Smaller areas are also found in Hillsborough,
Polk, Pasco, Hernando, Citrus, Gadsden, Madison, Hamilton and Suwannee Counties
Descriptions of correlated mapping units of Arredondo soils from published
soil surveys are presented below.
A profile description of Arredondo loamy fine sand, 2 to 7 percent slope,
occurring in Alachua County (37) is as follows:
0 to 8 inches, light brown or bro-wnish-gray nearly loose loamy fine
sand containing a small amount of organic matter.
8 to 16 inches, light broiun or light yellowish-brown nearly loose
loamy fine sand.
16 to 20 inches, light yellouish-brown or brownish-yellow friable loamy
20 to 40 inches, light yellowish-brown or grayish-yellow moderately
friable loamy fine sand.
The surface soil varies from grayish-brown to dark gray and contains
considerable organic matter. Where areas border Gainesville soils, Arredondo
soils are browner in both the surface soil and subsoil than the typical
Arredondo. In some areas fine sandy loam or sandy clay loam occurs at
depths of 20 to 30 inches or more below the surface. In places some chert
gravel is scattered over the surface and mixed with the soil.
Arredondo-Fellow:ship loamy fine sands is a complex consisting mainly of
Arredondo loamy fine sand, with small areas of Fellowship loamy fine sand
and soils intermediate in characteristics between the two soils. Most
areas have a slope of 2 to 7 percent, but some small areas have 7 to 15
Arredondo loamy fine sand-fine sands is a soil complex occurring in
the western part of Alachua County in association with Gainesville and
Lakeland soil. This complex consists mainly of Arredondo loarmy fine sand,
but there are small areas of Arredondo fine sand that could not be readily
separated on the soil map. Most of the areas are undulating to gently
The approximate acreage and proportionate extent of Arredondo soils in
this county are as follows:
Arredondo-Fellowship loamy fine sands - 2,567 acres - - 0.Vi
Arredondo loamy fine sand-fine sand - -27,430 acres - -.8
A profile description of Arredondo fine sand, 0 to 5 percent, occurring
in Gadsden County (38) is as follows:
Ap 0 to 5 inches, dark grayish-brown (10YR h/2) fine sand; weak, fine
crumb structure; loose; medium content of organic matter; few
fine roots; strongly acid; boundary clear and smooth.
A2 5 to 16 inches, grayish-brown (10YR 5/2) fine sand; weak, fine crumb
structure; loose; few fine roots; medium acid; boundary clear
C1 16 to 34 inches, yellowish-brown (10YR 5/h) fine sand; weak, fine
crumb structure; loose; few small pebbles, medium acid; bound-
ary clear and wavy.
C2 34 to 43 inches, light yellowish-brown (10YR 6/L) fine sand; weak,
fine crumb structure; very friable; many fine pores; few fine
roots: very few medium to large pebbles of moderately hard
sandstone; medium acid; boundary gradual and wavy.
D1 b3 to 51 inches, light yellowish-brown (10YR 6/4) loamy fine sand;
common, medium, faint, very pale brown (10YR 7/3) and common,
medium, faint, yellowish-brown (10YR 5/4) mottles; moderate,
fine crumb structure; friable; common fine pores; few root
channels; few small, medium and large pebbles; medium acid;
boundary gradual and irregular.
D2 51 to 66 inches plus, gray (I(0R 6/1) sandyclay loam with common,
medium, distinct, yellowish-brown (10YR 5/6) and common, fine
prominent, yellowish-red (5YR 4/8) mottles; moderate fine, sub-
angular blocky and moderate, medium crumb structure; friable;
common fine pores; few fine root channels; few small, medium
and large pebbles; medium acid.
The surface layer ranges from dark grayish-brown to dark gray in color
and from 3 to 6 inches in thickness. The subsurface layer ranges from
grayish-brown to gray in color and from 4 to 11 inches in thickness. The
C horizon is light yellowish-brown to yellowish-brown. Fine-textured materials
are generally below a depth of h2 inches.
The approximate acreage and proportionate extent of Arredondo soils in
this county are as follows:
Arredondo fine sand, O to 5% slopes - - -143 acres - 0.1%
Arredondo fine sand, 5 to 8% slopes - - -3h2 acres - - 0.1%
8 to 12% slopes - - - - - -- -231 acres - - 0.1%
12 to ho slopes - - - - - - 204 acres - - 0.1%
A profile description of Arredondo fine sand, level phase occurring in
Hillsborough County (25) is as follows:
0 to 6 inches, very dark grayish-brown to grayish-brown fine sand;
contains a moderate amount of partly decayed organic matter and
a few small rounded pebbles; a few small rounded pebbles are
scattered on the surface.
6 to 28 inches, dark yellowish-brown to yellowish-brown fine sand;
contains a few phosphatic pebbles.
28 to 42 inches plus, yellowish-brown to brownish-yellow fine sand;
contains a few phosphatic pebbles.
In some places the surface layer is up to 8 inches thick. The horizons
below the surface layer vary from light yellowish-brown to yellowish-
brown or yellow to brownish-yellow. This soil is slightly acid to medium
acid. Internal drainage is rapid and surface runoff is medium. The gently
undulating phase has 2 to 5 percent slopes, but short slopes near sinkholes
and streams may be steeper.
The approximate acreage and proportionate extent of Arredondo soils in
this county are as follows:
Arredondo fine sand, level phase - - - 10,251 acres - - 1.5%
Arredondo fine sand, gently undulating phase -4,777 acres - - 0.7%
A profile description of Arredondo fine sand on 0 to 5 percent slopes
occurring in Suwannee County (22) is as follows:
0 to 6 inches, loose, dark grayish-brown fine sand with a few small phos-
6 to 60 inches, loose, brownish-yellow fine sand -ith a few small phos-
The color of the surface soil ranges from gray to dark grayish-bron.
This layer also ranges in thickness from about 4 to 7 inches. The color of
the subsurface layer ranges from pale brown to brownish-yellow. Texture of the
subsurface layer is usually fine sand but a fetw loamy fine sand areas are in-
cluded. In a few small areas, phosphatic pebbles are much more numerous than
typical. Fine-textured or gravelly substrata underlie some areas at 48 to 60
inches below the surface.
The approximate acreage and proportionate extent
this county are as follows:
Arredondo fine sand, 0 to 5% slopes - - -
Arredondo fine sand, 5 to 8% slopes - - -
Arredondo fine sand, 8 to 12%f slopes----
Arredondo fine sand, moderately shallow,
0 to 51 slopes - - - - - - -
Arredondo fine sand, moderately shallow,
5 to 8% slopes - - - - - - -
t of Arredondo soils in
531 acres -
- - 2.2%
- - 0.5%
- - 0.1%
- - 0.1%
acres - - 0.1%
PHYSICAL, CHEMICAL AND MIIERALOGICAL PROPERTIES
Results of physical, chemical and spectrographic analysis of several
Arredondo profiles from Alachua, Madison and Suuannee Counties Iere reported
by Gammon et al. (12). Mechanical analysis, pH and moisture equivalent are
summarized as follows:
Table 1 Chemical Analysis of a typical Arredondo Loamy Fine Sand Profile in Alachua County (12).
Horizon Depth Organic Matter Total Nitrogen Total Phos-
Inches Percent Percent Percent
Moisture Cation Exchange
Medium sand and fine sand are the dominant particle sizes throughout the
entire profiles, and all horizons are sandy in nature. The surface layers
range from 85.2 to 89.t percent sand, h.9 to 9.3 percent silt, and 2.5 to 9.0
percent clay. The pH of the surface layers varies from 5.17 to 6.20 and the
B horizons range from 5.28 to 5.97. The moisture equivalent varies from 6.22
to 13.69 in the surface soil.
A representative chemical analysis of an Arredondo loamy fine sand profile
is shown in Table 1. The surface soils of three different Arredondo profiles
have cation exchange capacity values varying from 10.98 to 11.68 me./l00 g.
The exchangeable calcium varies from 1.13 to 3.82 me./100 g. in the surface
soil, and generally decreases with depth. Exchangeable potassium and mag-
nesium are relatively low throughout the profiles, while total phosphorus var-
ies from 0.030 to 0.296 percent. Organic matter contents range from 3.32
to l.67 percent in the surface horizons, but are markedly less in the lower
In the total rough estimate spectrographic analysis of Arredondo soils,
strontium, barium, iron, vanadium, chromium, manganese, nickel, zirconium,
copper, titanium, boron and zinc were found in small amounts.
MANAGEMENT OF ARREDONDO SOILS
In Alachua County, about 70 percent of the Arredondo-Fellowship loamy
fine sand is cultivated. A small percentage is in pasture and the rest is
in hardwoods and loblolly pine. This soil is used to group corn, peanuts, vel-
vet beans, sugarcane and vegetables.
If the soil is well managed, crop yields are fair to good and improved
pastures are generally good. Liberal applications of mixed fertilizers are
needed each year for crops and pastures. Lime is needed every third or fourth
year on citrus groves and pastures. Some crops such as vegetables need to be
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Air drainage is generally good because of the gently undulating relief.
Therefore, the soils on slopes are better suited to citrus than the level areas.
During intense rainfalls cultivated soils on slopes greater than 5 percent may
be damaged by erosion. Because of low content of organic matter, low moisture-
holding capacity and rapid leaching of plant nutrients: this soil is not well-
suited to most tilled crops. Good management practices should include cover
crops, irrigation, lime and liberal application of fertilizer.
Average acre yields of crops that may be expected over a period of years
on each soil in Alachua County, Floridal (37), are shown in Tables 2 and 3.
Tables L and 5 show yields of principal crops that may be expected on
Arredondo soils in Gadsden and Hillsborough Counties, respectively.
Because of the favorable surface relief and the nearly loose character
of the soil, nearly all of the rainfall is absorbed. However, during intense
rains, clean-cultivated sloping areas may have some runoff and erosion.
Surface runoff should be controlled on bare soil. The cover of plants
retards runoff when rainfall is intensive and also reduces the movement of
soil particles during strong windstorms. Vegetation is better than most
mechanical means of retarding soil erosion. Contour cultivation and strips
of close-growing crops should be used on sloping cultivated areas to control
runoff and soil washing.
Although rainfall is usually sufficient to supply the moisture that is
needed by most general crops, the use of irrigation for crops of high value
is increasing. Hammond and Popenoe (1) made a soil moisture study of Arredondo
IBased on prevailing management practices.
Table 2 Estimated Yields of Principal Field Crops (based on prevailing management practices).
Corn Peanuts Corn & peanuts1 Cowpeas Bright tobacco Sugarcane for
Soil Type Nuts Hay interplanted for hay syrup
Bu? Bu Lb. Tons Bu. Lb. Tons Lb. Gal.4
loaiy fine sands 18 30 650 .7 15 550 1.0 --- 250
Arredondo loamy fine
sand-fine sand 16 25 650 .7 12 550 1.0 50 250
iPeanuts with corn in every other row of peanuts.
2yields of corn expected without use of fertilizer.
yields expected when fertilized at planting time uith 200 pounds of 5-7-5 or similar mixture containing 75
pounds of zinc sulfate per ton and 100 pounds of nitrate of soda or sulfate of ammonia O0 to 50 days after
With improved varieties, syrup yields may be doubled.
Table 3 Estimated Yields of Pasture and Truck Crops (based on prevailing management practices).
Permanent Beans Beans Cabbage Cucumbers Eggplant Pepers Sweet Okra Squash
Soil Type pasture lima string Potatoes
Cow days1 Crates Crates Tons Crates Crates Ccates Bushels Crates Crates
loamy fine sands 150-300 85 90 8 150 135 175 100 125 135
Arredondo loamy fine
sand-fine sand 125-250 80 90 7 150 125 175 100 125 135
1Number of days per year that 1 acre of pasture will support a cow without injury to the pasture.
Table h Estimated Acre Yields of Principal Crops and Carrying Capacity of
Pasture under Two Levels of Management in Gadsden County, Florida (38
Soil Type Corn Peanuts Oats Pasture
A B A B A B A B
Bu. Bu. Lb. Lb. Bu. Bu. Cow Cow
Arredondo fine sand,
0-5% slopes 25 45 1000 1250 20 0 h10 2h0
Arredondo fine sand,
5-8% slopes 15 30 800 1000 15 35 120 220
8-12% slopes --- -- -- 120 2W0
12-l.0 slopes- ---- -- --
In Columns A are estimated yields of crops and pasture under common management;
in Columns B are those under the highest level of management feasible. Dashed
lines indicate that the crop is not generally grown on the soil.
lNumbers of days a year that 1 acre of pasture will graze a cow without injury
to the pasture.
fine sand in a citrus grove and found that tensiometers were as useful as oven-
drying for estimating the soil-moisture content over most of the available
moisture range. At soil moisture conditions ;,here precise measurement for irri-
gation timing would normally be desired, the variance of sample means for the
tuo methods were about the same. With a uniform decrease in the soil-moisture
content, the variances of both methods decreased. Irrigation is profitable
only with good soil management that provides for the use of adequate amounts of
commercial fertilizer and manure, the planting of green manure crops and the
return of crop residues to the soil.
Small farm ponds, constructed in natural drains that have small water-
sheds are used to store water for irrigation. The site for a farm pond should
be carefully studied for it is necessary to know the storage capacity of the
Table 5 .
Estimated Average Acre Yields of Principal Crops under Two Levels of Management in
Hillsborough County, Florida (2h).
Sweet CroTider Citrus
boil Type Tomatoes Corn Polebeans Watermelons Corn Peas Fruit
A B A B A B A B A B A B A B
Bu. Bu. Doz. Doz. Bu. Bu. No. No. Bu. Bu. Bu. Bu. Bu. Bu.
Level phsse 110 180 400 500 100 160 275 00 20 40 110 190 330 500
lating phase 110 180 400 500 100 160 275 400 20 40 110 190 330 500
Yields in columns A obtained under common farming practices; those in columns B under more
proposed pond, the amount of water available and the suitability of the founda-
tion material. Spillways and dams should be carefully designed and constructed.
Rotations, Green Manure Crops and Poultry Manure
Crop rotation practices and the use of green manures are varied (37). In
pecan groves, inoculated clover for pasture and nitrogen has gained some accep-
tance. In a test of various green manure crops groun in a two-year rotation
with corn, Stokes et al. (35), found that the yield of corn following Cro-
talaria striata was 16.6 bushels; velvetbeans, 16.8 bushels; beggarweed, 12.0
bushels; cowpeas, 14.2 bushels; and Florida Pussley, 8.7 bushels. On coarse
sandy soils, continuous use of green manure crops is necessary for maintenance
When grown on the same plots every year, Stokes et al. (36) found that
interplanted corn and runner peanuts without zinc or fertilizer yielded 6.3
bushels of corn and 523 pounds of peanuts per acre, but 11.55 bushels of corn
and 89h pounds of peanuts when the land uas allowed to grow in native weeds
and crotalaria every other year.
Green manure crops and crop rotations are valuable for increasing or main-
taining the productivity of the soil (37). On the coarse sandy soils, green
manure crops are especially important to reduce losses of nutrients by leach-
ing and to protect the soil against erosion of the sloping areas of finer
Pot studies using millet and oats in Arredondo fine sand were used by Eno
(6) to evaluate three kinds of dry poultry manure ranging in amounts from none
to 20 tons per acre. A series of pots were also used that had nitrogen, phos-
phorus, potassium and calcium added in amounts equivalent to that contained
in 2, 4, 8 and 12 tons of manure. The 16- and 20-ton rates of manure reduced
the yield on the first crop of oats. Thereafter the yields increased with each
increase in application of manure. In general, the inorganic nutrients increased
the yields more than the same amounts supplied as manure. Laboratory nitri-
fication studies showed that not more than one-half of the nitrogen in these
manures became available during the first 6 weeks. This was much slower than
the conversion to nitrate from inorganic sources of nitrogen such as urea and
On Arredondo fine sand having a pH of 6.0 and an exchange capacity of
1'.7 me. per 100 grams, Smith, Thornton, Eno and Blue (32) found that the nitri-
fication of anhydrous ammonia was better than equivalent amounts of ammonium
sulfate at rates below the toxic level. Nitrification of anhydrous ammonia
and ammonium hydroxide were about the same, except at rates above 500 pounds
per acre where it appeared that anhydrous ammonia was slightly more toxic to
nitrification than ammonium hydroxide. This toxic effect may be caused by the
active combining properties of anhydrous ammonia. For all the materials tested,
the most nitrate was produced at about 500 pounds per acre of ammonia nitrogen;
higher rates inhibited nitrification.
Eno, Blue, Thornton and Smith (10) found that the nitrification rate of
anhydrous ammonia and ammonium sulfate in Arredondo fine sand was much higher
than in either Klej fine sand or Leon fine sand. They also compared the
nitrification of a solution composed of 66.8 percent ammonium nitrate, 16.6
percent anhydrous ammonia and 16.6 percent water with the nitrification of an-
hydrous ammonia and ammonium sulfate in Arredondo fine sand and found that
this solution nitrified less rapidly than either anhydrous ammonia or ammonium
sulfate. However, there was considerably more nitrate present in soils treated
with this solution, because a part of this solution was ammonium nitrate. A
reduction in the rate of nitrification of this solution might be expected be-
cause of nitrate ------ the end product of nitrification. On the other hand, the
rate of nitrification should be increased because of the increase in pH caused
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by the ammonia content.
Smith, Thornton, Ross and Eno (3L) found that Aldrin at rates of 2, h,
8 and 50 pounds per acre and Lindane (gamma isomer of benzenehexachloride) at
rates of 25, 50, 100 and 200 pounds per acre applied to Arredondo fine sand
in the laboratory had no effect on numbers of fungi, bacteria and actinomycetes
or on the evolution of carbon dioxide. These insecticides also did not affect
the germination of peas and beans. Aldrin had no effect on the germination
of oats. When treated with 25 or more pounds per acre of lindanereduction of
nitrification was highly significant in Arredondo fine sand; while 50 pounds
or more of this material significantly stimulated ammonification of cottonseed
meal. At the rates used, aldrin had no effect on either nitrification or ammoni-
fication. Lindane at rates of 100 and 200 pounds per acre decreased signifi-
cantly the growth of oats in greenhouse pots.
Smith, Thornton and Eno (31) made a greenhouse screening test of 10 insect-
icides (heptachlor, chlordane, methoxychlor, lindane, aldrin, toxaphene, diel-
drin, TDE, DDT and benzenehexachloride ) added to Arredondo loanm fine sand at
the rate of 12.5, 50 and 100 ppm. of the active ingredients. Benzenehexachloride
at 50 and 100 ppm. reduced the numbers of bacteria and increased the numbers
of fungi in the soil. About a month after application, the opposite effect
was observed.. Plate counts showed little effect on microorganisms from the
Ross (29) applied DDT, aldrin and chlordane to Arredondo fine sand at rates
of 0, 15, 30, 60 and 120 parts per million and found no significant effect on
nitrification. DDT stimulated ammonificatnion and chlordane had a slight effect,
but aldrin showed no effect,
Horn (20) noted that application of DDT to Arredondo fine sand resulted
in significant increases in the numbers of bacteria, actinomycetes and fungi;
but the increases were not directly proportional to the amount of DDT applied.
Applications of chlordane up to 50 ppm. increased the number of bacteria, re-
duced the number of fungi and had no significant effect on the number of ac-
tinomycetes. Aldrin applied at rates of 25 ppm. had no effect on the numbers
of bacteria, whereas 1, 2, h and 25 ppm. increased significantly the actino-
mycete population. Aldrin had little effect on the numbers of fungi.
Thornton (39) found that D-D was a toxic soil treatment and depressed
nitrification for the longest period, uhile EDB and chloropicrin were not as
toxic. The temperature of the soil had little effect on nitrate production.
There was a very rapid recovery of certain original microbial species or new
introductions of microbes quickly established themselves. This made respiration
studies of little value in studying the effects of fumigants on soil population.
Eno (7) made a laboratory study of nitrate production rates from 11 or-
ganic and inorganic sources of nitrogen during a six months period using
Arredondo fine sand. The original pH of the soils was 5.5. All soils received
calcium carbonate at the rate of 2000 ppm. Each source was added at rates
equivalent to 200 ppm. of nitrogen. The amount of conversion of the applied
nitrogen was calculated after subtracting the nitrate produced in the soil
without added nitrogen. In the six months period, between h0 and 6h percent
of the organic nitrogen and 65 and 82 percent of the inorganic nitrogen was
converted to nitrate.
Eno and Popenoe (11) found that the percentage survival of bacteria and
fungi in Arredondo fine sand exposed to gamma radiation decreased with each
increase in radiation dose to less than h percent at 1,02h kr. Bacteria re-
covered much more rapidly and completely from irradiation than the fungi.
After one month, the numbers of bacteria in the soil irradiated at the high-
est level greatly exceed the bacterial population in tie control. Algae were
not reduced in numbers as much as bacteria and fungi and some survived at 2,018
kr. Two days after irradiation with 1,02L kr., few nematodes remained in the
soil. Nitrate production decreased with each increase in dose of irrad)htion.
Carbon dioxide evolution and production of sulfate from elemental sulfur were
also reduced by irradiation.
Smith, Thornton and Killinger (33) studied the effects of soil-borne
organisms, seed-borne organisms and contaminants in commercial humus cultures
in a greehnouse experiment using virgin Arredondo fine sand and Alta bitter
blue lupine. The results showed that a pure culture lupine root-nodule bac-
teria gave a highly significant increase in the yield of lupine compared to
commercial humus culture. An application of clover-gras. hay at the rate of
four tons per acre significantly reduced the yields of I:.-.neon non-sterile
soil, greatly reduced nodulation of lupine plants inoculated with a commercial
humus culture, but had no effect when a pure culture was used. When grown on
soil which had been fumigated for three years consecutively with D-D and Dow-WJ
40, beans were poorly nodulated. The nodules were small in size, dull in color
and found mainly on the lateral roots; while plants grown on soils which were
not fumigated were well-nodulated and the nodules were larger in size, brighter
in color and distributed on both the tap and lateral roots.
Eno and Blue (9) compared the nitrification rates of Arredondo fine sand
for 28 days using various amounts of anhydrous ammonia, ammonium sulfate and
ammonium sulfate plus two tons of calcium carbonate per acre. They found
that nitrification proceeded best at 291 ppm. for anhydrous ammonia and ammo-
nium sulfate uith lime. The ammonium sulfate without lime was nitrified at a
low rate. The applications at 570 and 762 ppm. were nitrified at a very low
Eno (5) found that the rate of nitrification in soil contained in poly-
ethylene bags was equal to that contained in ventilated bottles, but no ni-
trate diffused through the polyethylene bags in 2h weeks. Field studies on
Arredondo fine sand showed that soil temperatures above freezing varied suffi-
ciently to result in considerable changes in the rate of nitrate production.
Eno and Blue (8) studied the effect of anhydrous ammonia on nitrification
and the microbiological population in Arredondo loamy fine sand. When applied
at rates of 100 and 250 pounds of nitrogen per acre, the numbers of fungi,
bacteria and actinomycetes were decreased. They concluded that none of the
changes are likely to disturb permanently the ecological balance in the soil.
Placement of Nutrients
Blue and Eno (1) made a study of the effects of variations in soil mois-
ture and pH on retention of anhydrous ammonia by Arredondo loamy fine sand,
and found that both moisture content and pH affected the retention of ammonia.
Arredondo soil, with relatively high exchange capacities and pH values near
5.5 held large amounts of ammonia. Losses during application were probably
negligible. Low moisture content, high pH and low exchange capacity was the
poorest combination for retention of ammonia. Sweeps welded to the knife-
type injectors made lateral openings in the soil which allowed the ammonia to
come in contact with a greater volume of soil and increased absorption.
The distance of movement of ammonia was relatively small. The capacity
for retention of ammonia by most soils was rather large. The actual concen-
tration in the soil near the injector row was in excess of 10 times the per
acre rate. Field retention of ammonia was found to be quite variable among
soils and the loss of ammonia may be as much as 75 percent on the coarser,
sandy soils. In some cases this loss may prevent the economical use of anhy-
Blue and Eno (2) studied the retention of anhydrous ammonia in sandy soil
and found that Arredondo loamy fine sand held 893 ppm. of ammonia nitrogen by
the laboratory procedure at 10 percent moisture. A field sample contained
7hSppm. of ammonia nitrogen which showed that the retentive capacity of the
soil was approached at the point of injection. At l.4 percent moisture the
percentage of retention was only 30 percent of the amount at 10 percent mois-
ture using the 100 pound rate of application.
Retention and Levels of Boron
Winsor (43) applied borax to Arredondo loamy fine sand at rates of 0, 100,
h00 and 1600 pounds per acre. After four months, analysis of the boiling water
extractable boron showed penetration into the subsoil of Arredondo loamy fine
sand. The maximum amount from the 100 pound rate was found in the 21 to 28-
inch depth. The maximum amount was not found at the 3h to k2-inch depth until
2h months after application of the borax.
In Arredondo loamy fine sand, Winsor (l1) found that the penetration of
boron was rather rapid for ki months and portions of a one pound application on
the surface were detected by soil analysis from the 35 to h2 inch depth. Dur-
ing an 11i month period, penetration continued but at a reduced rate. There
was a large loss of boron from the topsoil, but the fine-textured subsoil re-
tarded further penetration. From an application of 100 pounds of borax per acre,
65 percent of the boron was retained in the 0 to 42 inch zone.
Winsor (42) noted that hogging-off of corn and peanuts for 12 consecutive
years on Arredondo fine sand either maintained or increased the boiling-water
extractable boron; but where the soil was planted to crotalaria every second
year through the 12-year period and the crotalaria plowed under before the crop
of corn and peanuts, the boron was increased an average of t7.3 percent. This
result was obtained without the use of lime, fertilizer or other minor elements.
Samplings of Arredondo loamy fine sand throughout the rainy season remained con-
stant at 0.17 ppm. of boron, while the boron in this soil decreased to 0.1 and
0.12 ppm. in the dry months when plants most often exhibit boron-deficiency
Winsor (kI) found that the growth of Jackson soybeans on Arredondo fine
sand was from poor to medium at 0.06 ppm. of boron, but maximum heights and
yields were obtained at 0.12 ppm. He (45) also found that butterbeans and Ford-
hook limas failed in 1959 with native boron at 0.08 ppm., but yielded well in
1960 with boron supplemented to 0.12 and 0.17 ppm. on Arredondo fine sand.
Pastures: Ruelke (30) established plots of Pensacola and Argentine bahia-
grass, Coastal and Suwannee bermudagrass and pangolagrass on Arredondo loamy
fine sand on the Agronomy Farm at Gainesville, Florida. The effect of three
rates of nitrogen (100, 200 and 00 pounds per acre) and two management treat-
ments (continuous grazing, simulated by cutting, and reserved grazing, simu-
lated by leaving a cover of grass in the fall) were studied.
The results showed that the total annual yield of forage was essentially
the same on plots which were cut continuously as on those plots which produced
reserve forage. Under similar management and fertilizer treatments, there was
little difference between the productive capacity of the various grasses. The
yield of grasses was nearly doubled when nitrogen was increased from 100 to
400 pounds per acre. The greatest response to nitrogen occurred when the rates
were increased from 122 to 200 pounds per acre. Increasing nitrogen to 400
pounds gave smaller increases in the yield of forage. Increasing the rates of
nitrogen usually increased the amount of winter injury in pangolagrass. Despite
this fact, an application of nitrogen up to 200 pounds per acre annually pro-
duced more forage at the first cutting of pangolagrass than where 100 pounds
of nitrogen were used. Winter injury occurred in bermudagrass and bahiagrass
which received high rates of nitrogen, but these grasses were able to recover
without serious reductions in yield.
In an experiment on Arredondo loamy fine sand, Hoveland and McCloud (23)
found that the yield of forage increased as pearlmillet was permitted to grow
taller before clipping. The yield continued to be high over a longer period
of time with taller growing plants. Frequent cutting decreased the yield
throughout the season. When clipped at 12, 18 or 30 inches tall, height of the
stubble had no influence on the yield of plants. For plants 5h inches tall,
forage yield decreased as the cutting height was increased. In general, the
protein decreased as the plants were permitted to grow taller before clipping.
The height of stubble had little influence on the content of protein. It
was concluded that close grazing does not materially reduce forage yield or
protein content. The main factor affecting yield and protein content was the
height of the plants when grazing was begun.
Working with pot cultures, Harris, Clark and Gilman (17) found that sul--
fur in the fertilizer doubled the forage yield of oats. Without sulfur in
the fertilizer, the plants were a pronounced yellow color similar to symptoms
of nitrogen deficiency. Leaving phosphorus out of the fertilizer had no appar-
ent effect on the yield or growth of the oats.
Good and Blue (13) noted that the yields of Ladino clover were reduced
and plants were severely injured by the sting nematode Belonoleimus gracilis,
and yields were slightly reduced when Sclerotinia sclerotiorum was associated
with the sting nematode. It was concluded that the progressive decline in
yields and plant densities during the late summer was found to be associated
with plant parasitic nematodes and to a lesser extent with S. sclerotiorum.
Ladino clover in the check treatment remained vigorous during the late summer.
West and Prine (hO) studied the effect of climate on the carbohydrate
level in alfalfa and found that the total carbohydrate content of the roots
decreased in the summer from h0 to lh percent. They concluded that the fail-
ure of alfalfa to persist in Florida may be due to the long duration of warm
night and day temperatures. Alfalfa cut at the h-inch height had a cooler
microclimate and a higher carbohydrate content of the roots than when cut at
a 2-inch height.
Choate, McCloud and Hammond (3) conducted a pasture irrigation experiment
on Arredondo loamy fine sand near Gainesville which involved four depths of
wetting, two soil moistures ranges and four pasture species. The zone of
moisture withdrawal varied with the species. White clover withdrew little
moisture beyond a depth of twelve inches, whereas Hubam, bahiagrass and
pangolagrass withdrew some moisture to a depth of twenty-four inches. The
yield was greater for most of the species when moisture tensions were main-
tained at 200 cm. than at tensions of 800 cm. When irrigation was con-
trolled by tension measurements in the 18 to 2h inch zone, yields were only
slightly greater than the yields from the non-irrigation treatment. The
irrigation treatments did not extend the growth period of the clovers.
In a study of nutrient movement in St. Augustine grass growing on
Arredondo fine sand, Robertson (27) noted that movement was greatest in
the direction of moisture stress. Phosphorus moved away from and back to
the mother plant, but calcium did not move in the runners regardless of
moisture stress. Nitrogen movement was greatest away from the mother plant.
Pritchett and Nolan (26) grew coastal bermudagrass on Arredondo loamy
fine sand which was fertilized with various sources of potassium. They
found that finely divided materials of less than 35-mesh and of low water
solubility became available at a sufficiently rapid rate in the soil to
supply potassium to the plant in amounts equivalent to that from soluble
sources' (PL and K2SOh). In a short term experiment, increasing the size
of the particles decreased the crop yield and potassium uptake from soluble
materials as well as those of low water solubility. In a long term green-
house lysimeter experiment, leaching losses of potassium from KCL were 31
times as much as from slowly soluble sources such as IPO3 and K2CaP207.
Yields of the three crops increased as the size of the particles increased.
This was especially true for the slowly soluble materials, where the slower
rate of availability resulted in more uniform yields for the three successive
Corn: Homer, McCloud and Wofford (21) studied the effect of nitrogen
on corn yields and found that applicationsof nitrogen greater than 200 pounds
per acre failed to produce significantly higher yields, even with high popu-
lations. When spacing was varied at high nitrogen rates, yields of corn
leveled off at about 17,000 plants per acre. Four or five inches of supple-
mental irrigation in May and June did not increase the yield of corn sig-
nificantly. Early March plantings produced higher yields than late March
or mid-April planting. It was recommended that farmers plant less than
13,000 plants per acre on soil of good fertility unless they are entering
a corn growing contest. Nitrogen applications in excess of 100 to 130
pounds per acre (including that from a leguminous green manure crop) probably
would not be economical.
Harris, Bledsoe and Clark (16) grew corn on Arredondo loamy fine sand
in a greenhouse experiment and found that corn with a complete fertilizer
including the micronutrients appeared to grow normally. Where zinc was
not in the fertilizer, white bud developed; but all plants were not affected
and the affected plants tended to grow out of this condition. Without sulfur
in the fertilizer, the corn developed a fine stripe when it was about 5 inches
tall. As the plants grew, the stripes disappeared rather quickly and the corn
became a pale yellow color with the base and mid-ribs of the plants a pur-
plish color. Without zinc or sulfur, there was a significant decrease in
yield. In the second harvest from the same experiment, the lack of zinc
had no effect on the yield; but the lack of sulfur gave a highly significant
decrease in the yield of corn.
Using Arredondo fine sand, Robertson, Schroder, Lundy and Prine (28)
studied the effect of carbon dioxide on the yield of corn. In this experi-
ment, corn plants were grown in fiberglass-walled enclosures 8 feet square
and 8 feet high in which CO2 was released from tanks at rates up to one liter
per minute. Carbon dioxide at one liter per minute increased the yield of
corn 15 bushels per acre which was about equal to the drop in yield caused
by the enclosures. Chicken manure applied at the rate of 45 tons per acre
in the enclosures increased the yield 11 bushels per acre, but none of
these increases in yield were significant.
Oats: Harris and Gilman (18) grew oats on Arredondo fine sand using
complete and incomplete fertilizer treatments. The results show that nitrogen
and sulfur had a pronounced effect on the yield of oats. An application of
magnesium sulfate corrected in ten days the yellow color in oats due to sulfur
deficiency. Lime and phosphorus had no effect on yields even though no fer-
tilizer treatments had been applied to this soil since 1930. Nitrogen and
sulfur had an inverse effect on the chemical composition of the oats. That
is, suWfur decreased the nitrogen content while nitrogen decreased the per-
centage of sulfur.
Harris, Bledsoe and Clark (16) conducted field experiments on Arredondo
loamy fine sand and found that copper in the fertilizer materially increased
the yield of oats, which showed marked deficiency symptoms when copper was
not in the treatment. A small amount of copper was sufficient and a spray
was effective on oats. In one case, oats developed "grey speck" in an over-
limed situation. The overliming injury was corrected by an application of
Lupine: Harris, Bledsoe and Clark (16) planted blue lupine on Arredondo
loamy fine sand and observed that copper gave a highly significant increase
in the yield of lupine. In general, an application of an element tended to
increase the percentage composition of that element in the plant. They con-
cluded that many factors influence the composition of a plant; but the results
indicated that unbalanced nutritional conditions, such as may occur in Florida,
- 25 -
materially affected the chemical composition of plants.
Peanuts: Harris and Bledsoe (15) found that an application of copper
chloride to Arredondo loamy fine sand greatly increased the yield of Dixie
Runner, G-FA Spanish and Alabama Runner peanuts. The copper treatment improved
the grades of the peanuts by decreasing shrivels and increasing the size or
number of plump and sound nuts. Analysis of the plump and sound nuts indicated
that the copper treatment had no effect on the content of oil and nitrogen.
Copper sulfate applied in 1942 produced a pronounced beneficial residual
effect on the yield of Dixie Runner peanuts planted in 1945.
In a field experiment conducted on Arredondo loamy fine sand, Harris,
Schroder and Clark (19) found that close spacing was more effective on increas-
ing yields than fertilizer; but, at close spacings, fertilizer had an appre-
ciable effect on yield. Early Runner peanuts grown with fertilizer in close-
ly spaced rows produced the highest yield and grade of peanuts, with a yield
of 4,759 pounds per acre.
Vegetables: In a study conducted on Arredondo'soil, Jamison (24) noted
a very definite increase in yield of vegetables with irrigation. One-half
inch every six days was found to be satisfactory except for sweet corn, which
showed maximum increases with larger amounts of water. The weight and number
of ears of sweet corn increased as the amount of water applied increased.
With no irrigation, 10,708 ears per acre were produced; but with frequent water-
ing the number of ears increased to 28,344. Green beans with no irrigation
yielded only 24 bushels per acre, but with a heavy rate applied in split appli-
cationsthe yield was 291 bushels per acre.
It was also observed that aphid infestation and several important diseases
were more severe on the non-irrigated than on the irrigated crops.
Tung Trees: Drosdoff (4) noted that on some soils, such as the Arredondo
series, it was difficult to correct zinc deficiency of young tung trees by
applications of zinc sulfate to the soil. Generally a soil application of
2 ounces per tree was sufficient to control zinc deficiency, but in some cases
this did not give satisfactory control. In these instances it was necessary
to spray the trees with a mixture of 8 pounds of zinc sulfate plus 8 pounds of
hydrated lime in 100 gallons of water. Plantings of tung trees on newly cleared
land of the Arredondo series have shown severe zinc-deficiency symptoms.
Copper deficiency on tung trees has been reported on Arredondo sand and
loamy fine sand. About one ounce of copper sulfate per tree applied to the
soil was recommended to control copper deficiency of young tung trees. Soil
applications of copper sulfate often did not control copper deficiency, es-
pecially for the first two or three years of growth. Complete control was
obtained by spraying with a mixture of 8 pounds of copper sulfate plus 8 pounds
of hydrated lime in 100 gallons of water.
Manganese deficiency of tung trees has been observed on Arredondo loamy
fine sand. A soil application of 2 pounds of manganese sulfate per tree was
required to control the deficiency. Generally, when there was only a slight
manganese deficiency, 2 to 4 ounces of manganese sulfate per tree per year ap-
plied to the soil was sufficient. It has not been demonstrated that the con-
trol of slight manganese deficiency symptoms increased yield.
- 28 -
1. Blue, W. G. and Eno, C. F. Some aspects of the use of anhydrous ammonia
on sandy soils. Soil Sci. Soc. of Fla. Proc. 12: 157-164. 1952.
2. Blue, W. G. and Eno, C. F. Distribution and retention of anhydrous
ammonia in sandy soils. Soil Sci. Soc. of Amer. 18: 420-424. 1954.
3. Choate, R. E., McCloud, D. E. and Hammond, L. C. Depth and frequency
of supplemental irrigation of pastures. Soil Sci. Soc. of Fla. Proc.
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5. Eno, C. F. Nitrate production in the field by incubating soil in
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8. Eno, C. F. and Blue, W. G. The effect of anhydrous ammonia on nitrifi-
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9. Eno, C. F. and Blue, W. G. The comparative rate of nitrification of
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10. Eno, C. F., Blue, W. G., Thorntong G. D. and Smith, F. B. Interrelation-
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microorganisms, their metabolic processes and.the fertility of the soil.
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Leighty, R. G. and Smith, F. B. Physical, spectographic and chemical
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- 29 -
15. Harris, H. C. and Bledsoe, R. W. Nutrition and physiology of the peanut.
R. M. A. Project 488. Fla. Agr. Exp. Sta. Annual Report. p. 52. 1949.
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micronutrients and sulfur on the yields of certain crops. Soil Sci.
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20. Horn, G. C. The effect of certain insecticides on the flora of Arre-
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- 30 -
29. Ross, H. F. Effects of DDT, chlordane and aldrin on nitrification
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32. Smith, F. B., Thornton, G. D., Eno, C. F. and Blue, W. G. Interrela-
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