DEPARTMENT OF SOILS MIMEOGRAPH REPORT 64-2
PERRINE SOILS OF FLORIDA
L. G. Thompson, Jr., V. W. Carlisle,
R. E. Caldwell, and R. G. Leighty
Department of Soils
Agricultural Experiment Station
University of Florida
Introduction '. . . . . . . . .
General Characteristics of the Series .
Geology and Physiography . . .
Climate . . . . . .
Figure 1. Location of Major Areas of Perrine
Associated Soils ...... .
Official Series Description . . . .
. . 0 . I1
* 0 *
0 0 * 0 *
0 . 0 . . 3
Description of Major Mapping Units .. . . . . . . .
Physical, Chemical, and Mineralogical Properties .
Management of Perrine Soils .. . . .
Tomatoes . . . . . . .
Potatoes .. . .
Snap Beans . . . .. . . . .
Pole Beans . . . . .
Other Vegetables . . . . . .
Research on Perrine Soils ... . .
Fertility Experiments with Tomatoes .
Effect of Fungicides on Tomatoes . . .
Fertility Experiments with Potatoes . .
Water Control Experiments on Perrine Soils .
* 0 0 0 0 0 0 ..**
Estimated Yields . . .. . . . . . . . . . 20
Literature Cited . . . . . . .
. . . . . 21
General Characteristics of the Series
Perrine series consists of Low-Humic Gley soils of the Red-Yellow Podzolic re-
gion. They were developed from unconsolidated finely divided calcareous sediments.
These soils occur on level areas only a few feet above sea level and are naturally
very poorly drained, but some areas have been artificially drained by ditches and
canals. The texture of these soils is mostly silt loam. Perrine marl differs from
Flamingo marl in that it has a higher content of silt and a lower content of clary.
It differs from Ochopee fine sandy marl by having a lower content of fine sands mixed
with the calcareous materials. The surface soil varies from grayish-brown to dark
grayish-brown and from 6 to 10 inches in thickness. There may be a few small pale
yellow mottlings in the light gray color of the lower layers. The limestone is com-
monly from 18 to 36 inches below the surface of the soil.
The native vegetation is mostly sawgrass, saltgrass, sedges, reeds, mimosa,
buttonwood, and mangrove.
Perrine marl is used for potatoes, tomatoes, snap beans, and other vegetables.
Approximately 17,000 acres of this soil are used for these crops. With a high level
of management, good yields are obtained.
Geology and Physiography
Perrine marls have developed from unconsolidated finely divided calcareous sedi-
ments of recent geological origin that were mainly deposited in fresh w.ater. These
soils occur on nearly level areas only a few feet above sea level. They are poorly
to very poorly drained. They are underlain by Miami oolite or the Tamiami formation
in the west and by oolitic limestone in the south and east portions of Dade County,
Florida. During very high tides, some areas may be covered by brackish or salt
The climate of the Perrine marl area is humid and subtropical. Winters are
short and mild and summers are long and warm. Sea breezes from the Atlantic Ocean
and the Gulf of Mexico keep the temperatures moderate. Almost daily afternoon thun-
derstorms help to lower the summer temperatures. Frosts harmful to winter vegetables
have occurred at least once in lh out of 2h years, but in the other 10 years no frost
occurred at all.
j. " * *" *
Figure 1. Location of Major Areas of Perrine Marl and Associated Soils
The average annual temperature is approximately 740F., with maximums of about
1000F. during June to August and minumums of about 260F. in December to February.
The annual rainfall averages 63 inches with about three-fourths of the rain
falling from May through October, usually as heavy thunder storms. During some per-
iods there is too much rain for most crops and not enough at other times.
OFFICIAL SERIES DESCRIPTION
The Perrine series consists of poorly drained Low-Humic Gley soils chiefly in
the southeastern part of Florida. These soils are derived from recent unconsolidated
finely~ divided calcareous sediments (marl) that were deposited mainly in fresh iraters
or by the solution and re-deposition of calcareous materials. Perrine soils occur
on nearly flat areas that are only a few feet above sea level. They are generally
associated with the Rockdale soils and with Tidal swamp and Tidal marsh and less
commonly with the Ochopee and Flamingo soils. They are more poorly drained and coarse
textured than the Rockdale soils. The Perrine soils commonly are silt loam throughout,
whereas the Ochopee soils are sand, loamy sand, or sandy loam and the Flamingo soils
are silty clay loam or silty clay. The Perrine soils are of limited distribution
and extent but are locally important to agriculture.
Soil Profile: Perrine silt loam
Ap 0-8" Grayish-brown (10YR 5/2) silt loam; weak fine granular structure;
very friable; calcareous; clear i:avy boundary. 6 to 10 inches thick.
C1 8-16" Very pale brown (10YR 7/3) silt loam; weak fine granular structure;
friable; calcareous; gradual wavy boundary. 6 to 20 inches thick.
C2 16-30" Light gray (10YR 7/2) silt loam; weak fine granular structure; friable;
calcareous; abrupt irregular boundary. 12 to h0 inches thick.
D 30"+ Limestone.
Range in Characteristics: The principal types are silt, silt loam, and loam. A
very thin mantle, usually less than 2 inches, of organic matter may cover the surface
in the low or depressed areas. The surface soil may be light grayish-brown, or dark
gray. The C1 horizon is light brownish-gray or light gray, and the C2 horizon has
a few small pale yellow mottles. Depth to limestone commonly ranges from 18 to 36
inches. Peat may be present between the C horizon and the limestone. Some areas
are affected by brackish or salt water. Colors given are for moist soil. When the
soil is dry, values are one or two units higher.
Topography: Nearly level areas lying slightly above sea level. Locally the soil
has a very slight gradient toward the coast.
Drainage and Permeability: Poorly drained with slow or very slow run-off and very
slow internal drainage. Permeability is moderate to rapid.
Vegetation: Generally reeds, grasses, sedges, sa; grass, and a few cabbage palmettos
Salty areas are covered by mangroves and salt tolerant grasses. Areas once culti-
vated but now idle have a growth of dog fennel, smartweed, ragweed, coarse grasses,
Use: Undrained areas are not being used. Drained areas are used for the production
oT-truck crops during the winter and early spring months.
Distribution: Southeastern Florida; mainly east, south, and southwest of Homestead.
Type Location: Dade County, Florida; 2 miles east of U. S. Highway 1 at Florida City,
Series Established: Everglades Project Area, Florida, 19h$.
Remarks: The Perrine series, as now defined, includes the soils formerly classed
in the Tucker series.
National Cooperative Soil Survey
DESCRIPTION OF THE MAJOR LAPPING UNITS
The following profile description, approximate acreage, and proportionate
extent of Perrine soils appear in the current soil survey reports.
A profile description of Perrine marl occurring in Dade County (10) is as
0 to 8 inches, grayish-brown friable marl of silt loam texture; strongly alkaline
8 to 16 inches, very pale brown friable marl of silt loam texture; contains
several small shells or fragments of shells; strongly alkaline.
16 to 30 inches, light gray friable marl of silt loam texture; contains a few
fragments and small shells; strongly alkaline.
30 inches +, limestone.
The surface soil varies from light brownish-gray to dark grayish-brown in
color and from 6 to 10 inches in thickness. A thin layer of partly decomposed organic
matter covers the surface in some low-lying areas. The second layer ranges from
light brownish-gray to light gray and from 6 to 20 inches in thickness. There are
a few small pale yellow mottlings in the light gray color of the third layer. Lime-
stone occurs at a depth varying from 2h to 72 inches. There are some small areas
that consists of pale yellow to yellow marl from the surface down to the limestone.
Potholes that are slightly lower and may be covered with water for longer periods
occur in this soil.
Perrine marl, shallo'i phase, occurs in the southeastern part of Dade County
in association with other Perrine marls. Small areas extend into areas of Rockdale
soils-limestone complex which lie on a ridge extending from Florida City to Miami.
This shallow phase differs from Perrine marl in that limestone is found at depths
ranging from 12 to 2h inches.
Perrine marl, very shallow phase, is found in association with other Perrine
marls and Rockdale soils. It differs from Perrine marl in that limestone occurs
at depths of less than 12 inches.
Perrine marl, peat substratum phase, occurs in large areas and in association
with other Perrine marls and with Mangrove swamp (unclassified soils). It is found
in the southern part of the marl glades near Florida City. It differs from Perrine
marl in having a 12- to 18-inch layer of broun fibrous organic matter between the
surface layer of marl and the underlying limestone. The marl varies from 12 to 24
inches in thickness and from a silt loam to loam in texture. The depth to the under-
lying limestone ranges from 2h to 60 inches.
Perrine marl, shallow, peat substratum phase, is found in association with other
Perrine marls and Mangrove swamp (unclassified soils) in the western and southern
parts of the marl glades near Florida City. It differs from shallow phase Perrine
marl in that it has a 6- to 12-inch layer of brown fibrous organic material between
the surface marl and the underlying limestone. The marl varies from h to 12 inches
in thickness, and the limestone occurs at depths which range from 12 to 2h inches.
Perrine marl, tidal phase, occurs in narrow belts between the other Perrine
marls and the Mangrove swamp (unclassified soils). It is found near the coast, east
of Homestead and Perrine and south of Florida City. It differs from Perrine marl
in that it has slight amounts of salts in its various layers. The salts come from
the sea water that cover the soil during high tide. The native vegetation usually
consists of salt-tolerant grasses and mangrove trees.
The approximate acreage and proportionate extent of Perrine soils in this county
are as follows:
Perrine marl - - - - - - - - h1,l60 acres - 3.1%
Perrine marl, peat substratum phase - - $8,255 acres - 4.3%
Perrine marl, shallow phase - -- - - 67,191 acres - 5.0%
Perrine marl, shallow, peat substratum phase 16,031 acres - 1.2%
Perrine marl, tidal phase - - - - - 13,756 acres - 3.2%
Perrine marl, very shallow phase - - - 79,080 acres - 5.8%
PHYSICAL, CHEMICAL, AND MINERALOGICAL PROPERTIES
According to Malcolm (15) the finely divided calcareous sediments of Perrine
marl soils in Dade County are very similar to the limestone that is applied to cor-
rect soil acidity in other parts of Florida. An excess of calcium carbonate may
require some special treatment but it need not be an impossible barrier to successful
Perrine marl contains 90 to 95 percent calcium carbonate. Skinner and Ruprecht
(18) reported that in addition to calcium carbonate, a typical sample contained 2.11
percent silica, 0.26 percent magnesium, 0.15 percent phosphorus, 0.08 percent iron,
and 0.001 percent manganese. The content of nitrogen was 0.33 percent, indicating
about 6 percent organic matter. More recent analyses indicate that these results
are still typical for this soil. However, there are many samples which contain less
silica and the phosphorus content of the virgin soil is generally lower, especially
in the area southwest of Florida City. The marls analysed by Skinner and Ruprecht
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were mostly from East Glade and Franjo areas. The low content of silica precludes
the possibility of a significant clay fraction.
The Perrine marl soils vary in pH from 7.5 to 8.8. The samples brought directly
from the field are seldom above pH 8.0, probably because of the high content of car-
bon dioxide. Drying for long periods will raise the pH.
Mechanical analyses show that Perrine marl is dominantly a silt loam. More than
95 percent of a marl sample can be washed through a 200-mesh sieve. The remainder
consists of root fragments, other organic material, and pieces of shell.
From chemical and physical analyses, it is apparent that these marls would be
classed as high grade agricultural limestones. However, they are not recommended
for magnesium-deficient soils.
The Perrine marl is deficient in some plant nutrients and requires fertilizer
to produce maximum yields. It is deficient in nitrogen, phosphorus, potassium and
manganese. Research by Skinner and Ruprecht (18), establishing that additions of man-
ganese were essential for successful crop production on Perrine soils, changed Dade
County agriculture from organic gardening to commercial farming. Only one case of
magnesium deficiency has been reported in the area. Probably deficiencies of copper,
zinc, boron, and iron do occur under some conditions but no consistent response to
these elements has been obtained.
MANAGEMENT OF PERRINE SOILS
In Dade County, nearly all the cultivated land is on the marl and rocky soils
with the most extensive and typical marls belonging to the Perrine series (10).
The Perrine marls range from 5 to 8 feet above sea level and are poorly drained.
Some large areas have been drained artificially by canals. The undrained soils become
waterlogged and sometimes are covered by a few inches of water during the rainy
season. At some periods in the growing season they may become too dry for crop growth.
Therefore, these soils need irrigation as well as drainage.
The water management system consists of field ditches, laterals, and canals con-
taining some check dams and pumps. The canals and laterals are spaced at intervals
of one-half mile usually on the section and half-section lines. The field ditches
are spaced from 660 to 1320 feet apart and at right angles to the laterals. During
the normal winter season, this drainage is generally effective but pumping may be
needed during occasional wet periods and in the rainy season.
Experiments (10) show that a O0-acre field from which the water has been pumped
can be cultivated two eeeks earlier than a similar area without pumping. For econom-
ical pumping a 40-acre field is about the best size. A dike should be built around
the field to prevent surface water from entering from other areas. Since the rocks
are porous and conduct water, about h inches of marl are left between the bottom of
the ditches and the underlying rocks. Also, for better water control, a series of
check dams and pumps are needed in the main laterals and canals.
Perrine marl is generally strongly alkaline in reaction and low in organic mat-
ter, nitrogen, potassium, and available phosphorus. Because of the lack of enough
mineral nutrients for crops, frequent application of fertilizers must be made. The
amount of fertilizer applied varies from 700 to 3000 pounds per acre, depending on
the kind of crop grown. The mixed fertilizers generally used are 5-7-5 or h-8-8.
Minor elements such as copper, zinc, manganese, and boron are added to help increase
the yield and improve the quality of the crop. Some of the minor elements are ap-
plied with sprays and dusts used for disease and insect control.
The marl soils vary from 1 to 20 feet in depth. On the shallow marls, crop
yields are about the same as those on the deeper marls. However, it is desirable
to plant as early as possible on the shallow marls so the crops can mature before
the soil becomes too dry in late spring.
Tillage practices depend generally on the kind of crop grown. Tractor plowing
and disk harrowing are used to prepare the seedbeds. Roadways are made about 600
to 1320 feet apart.
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Tomatoes are planted in rows 5 to 7 feet apart and at intervals of about 20
inches in the ro'. A 6-8-6 fertilizer at the rate of 800 to 1200 pounds per acre
is applied at planting and at intervals of 3 or 4 weeks until harvesting begins.
Side dressings of 100 to 200 pounds of nitrate of soda, sulfate of ammonia, or nitrate
of soda-potash are applied in some seasons. Fifty pounds of manganese sulfate are
usually applied with the mixed fertilizer. After heavy rains, more fertilizer is
applied. Tomatoes generally yield 135 to 200 bushels per acre, but sometimes up
to 600 bushels.
Potatoes are planted at intervals of about 8 inches in the row with the rows
about 32 inches apart. Mixed fertilizer is applied at planting time at the rate of
1500 to 2000 pounds per acre. The fertilizer should analyze about 4-8-h and usually
includes 100 pounds of manganese sulfate per ton. On land previously planted to
potatoes, nitrogen fertilizer may be reduced to 2 percent. The fertilizer is applied
in the row beside and below the seed pieces. The potatoes are cultivated about every
14 to 21 days. All potato-growing operations are mechanized.
On Perrine marl, the average yield of potatoes is about 190 bushels per acre,
but yields vary from 80 to 500 bushels.
Snap beans are planted at the rate of three pecks per acre in rows 30 to 36
inches apart. To control weeds they are cultivated about every 7 to 10 days. At
planting time a h-8-8 or 4-7-5 fertilizer containing 100 pounds of manganese sulfate
per ton is applied at the rate of 800 to 1200 pounds per acre. A side dressing of
100 to 200 pounds per acre of ammonium sulfate may be applied. On new land, it may
be necessary to apply additional manganese to the plants in the dust or spray used
to control diseases and insects. On Perrine marl, the average yield of beans is
about 150 bushels per acre, but yields vary from 100 to 300 bushels.
Pole beans are planted in rows from h8 to 60 inches apart. Various structures
are used for the beans to climb on. Some farmers use posts at 30- to 50-foot inter-
vals, which extend 6 feet above the ground and are connected by 3 strands of wire.
At intervals of 9 to 12 inches, cord is tied to the wire in a vertical position.
Others use small stakes at intervals of 2h to 30inches in the row. The acreage of
pole beans is much smaller than that of snap beans.
Pole beans receive about the same rate of fertilizer as snap beans, but an addi-
tional 200 to 300 pounds per acre of mixed fertilizer is applied before the first
picking. Sometimes a topdressing of 100 to 200 pounds per acre of nitrate of soda
is applied at the first picking. Yields for pole beans are slightly higher than those
for snap beans.
Small acreages of other vegetables such as squash, cabbage, peppers, celery,
sweet potatoes, and corn are grown on the Perrine marls. From 1000 to 1800 pounds
per acre of h-7-5 or h-8-8 fertilizer which contains manganese sulfate are applied
to these crops. Sweet potatoes receive about 700 to 1000 pounds of a 3-8-8 fertilizer.
Corn grown after potatoes usually is not fertilized.
The average yield of squash is about 160 bushels per acre, but yields have been
as high as 275 bushels. The average yield of cabbage is about 7 tons per acre, but
yields vary from 3 to 12 tons.
In rotations, sesbania generally follows tomatoes, and velvet beans follow po-
tatoes. Although these cover crops usually are not fertilized, they grow large
during the summer months. Generally they are plowed under about 6 weeks before
planting the next crop of vegetables.
RESEARCH O" PERRINE SOILS
Fertility Experiments with Tomatoes
Malcolm (13) conducted a series of fertilizer experiments with tomatoes on
Perrine marl and found that 300 pounds per acre of P205 as triple superphosphate
gave the best yield when compared to 0, 75, and 150 pounds of P205 per acre. In
previous years, the best yields were obtained from either 75 or 150 pounds of P205
per acre. When sulfate of ammonia and urea nitrogen were applied at rates of 0, tO0,
80, 160, and 320 pounds per acre, the 160 pound rate gave the best yield. The 320
pound rate yielded only slightly less. In the potash test, the 200 pound rate of
K20 per acre wras the best, but results from the same treatment in other tests indi-
cated that there .ias no difference between the 200 and 300 pound rates. The no-potash
plots produced very poor yields which had a large amount of fruit affected by vas-
cular browning, commonly known as "gray wall". The time of application test showed
that late and extra applications of nitrogen were of no advantage. The poorest yields
were obtained on those plots where the first nitrogen side-dressing was omitted in
favor of a late and heavy application.
Malcolm (lh) found that the phosphorus content of tomato leaves was increased
significantly by applying 0 to 300 pounds of P205 per acre to the soil. The potas-
sium content of tomato leaves was I times as high on plots fertilized with 200 to
300 pounds of K20 per acre as on plots receiving no potassium for a number of years.
As the rate of potassium applied to the soil was increased, calcium, magnesium, and
nitrogen contents of tomato leaves decreased.
In an 8-year test, 100 pounds of P205 per acre gave the highest yield of mar-
ketable tomatoes. Soil that had been adequately fertilized for 7 years needed no
phosphorus. When phosphorus was added to the fertilizer, the yield of marketable
fruit decreased but the total yield was not decreased.
In the nitrogen experiment, best yields of tomatoes were obtained from 300
pounds of nitrogen per acre. Yields were about the same with 400 pounds per acre,
but in another test 00 pounds of nitrogen depressed yields.
As the rate of application of K20 was increased from 0 to 300 pounds per acre,
the yield and the proportion of marketable fruit increased. Uhen the soil was ade-
quately fertilized for 7 years, additional potassium increased the marketable fruit
but did not increase the total yield.
Borax at the rate of 25 pounds per acre did not increase tomato yields.
Malcolm (17) conducted phosphorus experiments with tomatoes on deep Perrine
marl and noted that this soil did not contain sufficient available phosphorus for
maximum growth, but released a small amount at about a constant rate year after year.
About 70-75 pounds of P205 per acre per year was the most efficient rate of appli-
cation. The highest rate of application of phosphorus gave somewhat lower yields,
which usually was due to secondary effects. The high phosphate plots gave the best
yield ever obtained during the last year, which showed that the amounts accumulated
up to this point were not harmful.
The application of phosphate to the soil affected to some extent the nitrogen,
phosphorus, and potassium contents of tomato leaves. As the rate of phosphorus ap-
plied was increased, the nitrogen content was decreased. This effect was more appar-
ent in seasons when nitrogen was deficient. The potassium content also decreased
as the rate of application of phosphate was increased, but was significant for only
a single season. As the rate of phosphate application was increased, the phosphorus
content of tomato leaves was increased. The calcium and magnesium content of tomato
leaves were not influenced by the application of phosphorus. The nitrogen-phosphorus
ratio in the tomato leaves was found to be the best indicator of an adequate supply
of phosphorus. The optimum ratio was found to be 12.5 to 1.
No foliage symptoms were observed that could be used to diagnose phosphorus
deficiency. A marl containing h0 pounds of P205 per acre, as determined by the acid
ammonium acetate extraction method, gave a profitable increase in yield from an ap-
plication of phosphate.
On Perrine marl, Westgate (20) compared 6 plowed with 6 mowed plots planted
to Grothen Globe tomatoes and found a significant difference in yield of 72 bushels
per acre the first year in favor of the mowed plots. In the second and third years
of this test, there was no significant difference in yields between the treatments.
A series of nitrogen fertilizer experiments were run by Skinner and Ruprecht
(18) with tomatoes on marl soils. Each year the plots were moved to another area.
The highest yields of marketable tomatoes uere obtained from plots which received
from 99 to 148 pounds of nitrogen per acre. Increasing the rate of nitrogen to 198
pounds per acre reduced the yields. Organic sources of nitrogen gave the best re-
sults, but almost as good results were obtained where only three-fourths or one-half
of the nitrogen was derived from an organic source.
Malcolm (12) found that the highest yields of tomatoes were obtained with 160
or more pounds of nitrogen per acre. The results indicated that cyanamid, sulfate
of ammonia, ammonium nitrate, urea, and tankage were all equally effective under
the conditions of the experiment. These results iere different from those obtained
by Skinner and Ruprecht (18) who found that the organic gave better results than
the inorganic sources of nitrogen.
The yields varied from year to year, but there was no indication that the check
or the plots receiving 40 pounds per acre of nitrogen were becoming progressively
poorer or that the rate of 320 pounds per acre of nitrogen application was damaging
The tomato leaves from plots receiving O0 to 80 pounds of nitrogen per acre
contained less nitrogen than the leaves from check plots that received no nitrogen.
As the rate of nitrogen application above 100 pounds per acre was increased, the
nitrogen content of the leaves also increased. The yields from the low nitrogen
plants give evidence of a deficiency of nitrogen during the major portion of the
growing season. The results shou that nitrogen fertilizer at heavy rates of ap-
plication is absolutely essential for the production of tomatoes on deep poorly
A series of tomato experiments by Malcolm (11) disclosed that manganese was
available in the cultivated marl soils. This was true on land that had been farmed
for only 4 or 5 years. On the newer land the addition of manganese to the fertilizer
increased the yield of tomatoes. No visible symptoms of manganese toxicity were
observed in tomatoes. Significant yield reductions, below the yields from the plots
receiving moderate amounts, resulted from the use of 100 pounds of MnO per acre on
tomatoes. Manganese should be added to the fertilizer in quantities sufficient to
give the highest yield, but caution should be used to avoid larger quantities which
could cause yield reductions.
Fiskel, Forsee and Malcolm (5) found that tomatoes developed symptoms of extreme
manganese deficiency on virgin marl soils.
Effect of Fungicides on Tomatoes
Borders (1) studied the effect of several new fungicides on Grothen Globe to-
matoes planted on Perrine marl. The first 2 applications were made 7 days apart
and the next 10 applications at $-day intervals. All dithio-carbamate sprays except
zerlate controlled late blight in the field under extremely severe blight conditions.
The carbamate gave equally good control of early blight which uas moderately severe.
The addition of DDT to the spray gave a highly significant decrease in the yield
In a test of 16 selections of tomatoes on Perrine marl several selections were
found to be resistant to late and/or early blight.
On marl soils, using a split schedule of 2 applications of raneb to a single
application of zineb as the standard, Conover (2) found that spray applications of
Thylate, Thioneb, Captan, Phaltan, and Dyrene were not as good as the standard but
showed moderate control of late blight of tomatoes.
Fertility Experiments with Potatoes
Fifield and Wolfe (L.) conducted fertilizer experiments on the marl soils of
Dade County, Florida, and found that 1500 to 2000 pounds of h-8-9 or 3-12-8 gave
the highest yield of potatoes. In most instances the most profitable amount was
1500 pounds. In 4 out of 5 years a l-8-5 fertilizer with 33 percent of the nitro-
gen derived from organic sources yielded as well as fertilizers containing a higher
percentage of organic-derived nitrogen. Milorganite, blood-and-bone tankage, and
dried blood slightly outyielded the other sources. Fish scrap, cottonseed meal,
urea, and cyanamid yielded slightly less and about the same as fertilizers in which
all their nitrogen was derived from sulfate of ammonia, nitrate of soda, or ammoniuml
phosphate. Urea and cyanamid both produced good yields and were among the treatments
showing the lowest cost of fertilizer per bushel of potatoes harvested.
When the sulfate and nuriate forms of potash were compared, there were no sig-
nificant differences in yield.
Additions of manganese sulfate in amounts equivalent to 65 pounds of MnO per
ton of fertilizer gave as good yields as larger amounts. The results indicated that
after 5 years of successive applications manganese sulfate could be omitted for at
least one year without decreasing the yield.
Applications of copper sulfate, iron citrate, borax, sulfur and calcium sulfate
failed to give a profitable increase in yield.
When applied at 6 or 8 tons per acre with commercial fertilizer, manure increased
the yield slightly, but not enough to pay for the cost.
Westgate (i1) found that potato yields were not reduced on Perrine marl by
decreasing the nitrogen in the fertilizer from h to 2 percent. Then the nitrogen
was left completely out of the fertilizer, the yields were decreased under some con-
ditions. It is standard commercial practice to use h percent nitrogen in the fer-
tilizer for potatoes and other vegetables on Perrine marl, even when the nitrate
nitrogen levels are high.
Six standard potato varieties were compared to 23 late blight resistant potato
hybrids developed by Dr. Donald Reddick, New York State College of Agriculture, Ithaca,
New York. The plots were not sprayed, but no late blight developed on the hybrids,
with the best hybrids yielding 13h bushels per acre. The disease was severe in the
area and unsprayed Pontiac potatoes yielded only: bushels per acre.
On cultivated Perrine soils, Malcolm (11) found that manganese treated plots
yielded about the same as the check plots. No 'isable symptoms of manganese toxicity
There observed on the potatoes, yet there were significant yield reductions on the
plots receiving 75 pounds of MnO per acre. Applications of 37.5 pounds of MnO per
acre did not reduce fields.
In nitrogen experiments with potatoes on marl soils, Malcolm (12) found that
the soil supplied the nitrogen required by the potatoes. The results indicate that
the nitrogen was supplied to the soil by some natural :ieans. The soil had been cul-
tivated too long for the original organic matter to supply sufficient nitrogen for
the growth of potatoes. A cover crop of sesbania had been used on this land in suam-
mer, but nodule development was too poor to supply the large quantity of nitrogen
needed. The results from these plots and observation in the area indicated that
nonsymbiotic fixation of atmospheric nitrogen was taking place.
In phosphorus experiments with potatoes on Perrine marl, Malcolm (16) found
no significant difference in yield for the h years or for any single year. In the
third year, the check which had received no phosphorus produced the highest yield.
As the application of phosphate gave no significant response: it was concluded that
the soil contained sufficient available phosphorus for potatoes. Growing potatoes
for b years did not reduce the phosphorus supply to a critical level. When 870
pounds of P20g per acre as triple superphosphate were applied over a period of it
years, no toxicity resulted.
Conover and Wolfenbarger (3) nade a test on inarl soils of various methods to
control root-knot nematodes in potato fields and found that calcium cyanamide, D-D,
and ethylene dibromide had no effect on yield and 93 percent of the tubers showed
nematode infestation. Plots treated with methyl bromide gave the highest yield of
potatoes and the lowest amount of tuber infestation which was 26 percent. Weed killers,
such as 2-h-D amine and sodium chlorate, resulted in next to the lowest amount of
tuber infestation (57 percent). When the weed Colocasia esculenta was eradicated,
the quantity of tuber infestation was 80 percent and for fall plowing 83 percent.
In another test, D-D at rates of 176, 335, L4h4 and 1608 pounds per acre failed
to influence nematode infestation or yield of potatoes.
Malcolm (15) noted that all of the evidence indicated that the supply of cal-
cium was adequate. T1hile the high pH causes many people concern, it appears to be
of little consequence to the plants. With proper seed disinfection, potato scab
is not a serious problem on these soils in most years. As sources of nitrogen, ni-
trate of soda or ammonium sulfate gave equally good results for potatoes over a
period of years.
When adequate fertilizers are used, the yields of vegetables on these soils
are equal to or better than those obtained in other areas of Florida. Because of
the seasonal advantage, the net returns are generally better than in other areas.
The marls do have some serious disadvantages. During the summer months, cul-
tivation is not practical because the soil is subject to flooding. Shallow depth
to the water table level often limits the effective depth of the marl during the
winter cropping season .. This interferes with nitrification and root growth and
sometimes with cultivation and other tillage practices. As the marl is particularly
treacherous when it is wet, ground spraying may have to be abandoned at the most
critical time because the bearing value of wet marl is too low to support most farm
machinery. A high clearance crawler tractor has been developed to offset the poor
bearing quality of these soils.
When calcium cyanamid is applied to the soil, it usually retains its phytotox-
icity for weeks or even months. It may be safely applied to marl the same day that
potatoes or beans are planted without inhibiting sprouting or germination.
Considering the success of vegetable crops on marl soils, the conclusion is that
there is no such thing as too much calcium carbonate. Although the calcium must be
balanced by other plant nutrients, no special chemical compounds or complicated art
is needed to make these nutrients available.
Water Control Experiments on Perrine Soils
Gallatin (6) reported that pumping was not necessary on the water-control ex-
perimental plots in 1951. The increase in chlorides during the year was due to low
rainfall and a carry-over of residual chlorides. Some areas which had been farmed
successfully in previous years could not be used in 1951 because of high chloride
r:cncentrations. Results show that salt water will move inland through unprotected
ditches and contaminate the surrounding land. To keep sea water from moving up the
canals, barriers are effective. When pumping water from deep rock ditches is com-
pared to pumping from marl seal ditches, results show that chloride concentration
has remained lower in the area of marl seal ditches, although this area is located
closer to the bay.
In marls where the concentration of chlorides exceeds 250 ppm., snap beans should
not be planted. Potatoes, tomatoes, cabbage, and broccoli are more tolerant and
can be planted on land where the starting concentration is not more than 1000 to
1200 ppm. As the chlorides move toward the surface during the growing season, deep-
rooted crops are more tolerant than shallow-rooted crops. Where the plants have been
bedded by cultivation, good crops of tomatoes have been produced where the chloride
concentration at the surface was 15,000 ppm., but only 2000 to 3000 ppm. in the root
Gallatin (7) found that it is possible, by pumping, to get the land ready for
planting 2 to 3 weeks earlier than adjacent areas which were not pumped. The main
advantage of pumping is to protect crops against damage from rains coming late in
the growing season. In areas protected by pumping there has been no serious damage,
but in adjacent unprotected areas, the crops have been frequently damaged. by too
Gallatin (7) noted that barriers were effective in keeping chlorides from moving
up canals and ditches. As some crops are more tolerant to chlorides than others,
the soils should be sampled to determine concentration before planting. Then suitable
crops may be selected. Factors influencing chloride tolerance are: types, amounts,
end placement of fertilizers; cultural practices; rainfall; and organic matter.
After the plants are established, bedding-up the surface soil to raise the chlorides
above the root zone has been considered to be very important.
With almost normal rainfall during the summer of 1953 and a recharge of the
water table from the north, Gallatin (8) noted that a large portion of the contam-
inated area was flushed relatively free of chlorides. Because of a faulty barrier
in a ditch, the concentration of chlorides increased from 400 ppm. to 15,000 ppm.,
and resulted in serious damage to potatoes.
A low marginal area was diked for chloride control. Due to normal rainfall,
this area was low enough in chlorides to be planted for the first time in several
Gallatin (9) observed that, on farms not protected by pumps, the loss of crops
in 1953-54 season was extensive due to the inability to remove surface water from
the fields. The station farm, which was protected by pumping, saved all the crops.
At the start of the 1954-55 season, there was a long period of high water table.
The assurance of being able to plant at the proper time and to harvest the crop was
made possible by pumping and is essential to successful farming of these naturally
poorly drained soils. The rate of seepage from a 2-foot head through a marl sealed
ditch was only 0.10 cubic foot per second per mile which was an insignificant amount
compared with the seepage reported from a 2-foot head through a deep rock ditch.
It appears that rainfall is the most important factor in controlling chlorides.
Barriers are effective in keeping brackish-water from moving up the canals, but the
many ditches and small canals with no barriers reduce the effectiveness of the bar-
riers considerably for preventing salt intrusion.
Low dikes near the coast have been effective in keeping out fall and spring tides
in the marginal areas that are 1 to l1 feet above the mean sea level. Results from
these areas show that no pumping should be done from deep rock ditches adjacent to
the coast, because heavy pumping reduces the head of fresh water and allows salt
water to move in from the bay.
The estimated yields of principal crops on Perrine marl in Dade County (10)
are as follows: tomatoes, 135 to 200 bu./acre; potatoes 80 to 500 bu./acre; snap
beans, 100 to 300 bu./acre; pole beans, 125 to 350 bu./acre; squash, 150 to 250
bu./acre; and cabbage, 3 to 12 tons/acre.
- 21 -
:1. Borders, H. I. Control of Tomato Diseases.
Sta. Annual Report. p. 199. 1946.
2. Conover, R. A. Control of Tomato Diseases.
Sta. Annual Report. p. 345. 1957.
State Project 291.
State Project 291.
Fla. Agr. Exp.
Fla. Agr. Exp.
3. Conover, R. A. and D. O.
Nematode on Marl Soils.
p. 249. 1950.
Wolfenbarger. Studies on the Control of the Root-Knot
Non-Project Studies. Fla. Agr. Exp. Sta. Annual Report.
4. Fifield, W. M. and H.
Soils of Dade County.
Fertilizer Experiments with Potatoes on Marl
Exp. Sta. Bul. 352. 1940.
5. Fiskel, J. G. A., W. T. Forsee, and J. L. Malcolm. Some Manganese-Iron Relation-
ships in Tomato Fruits Grown on Marl, Peat and Sand Soils. Fla. State Hort.
Soc. Proc. 66:159-166. 1954.
6. Gallatin, H. M. Irrigation, Water Control, Chloride Tolerance and Intrusion
Studies on Rockdale and Perrine Marl Soils of the Homestead Area in 1951. Fla.
Agr. Exp. Sta. Annual Report. p. 289. 1952.
7. Gallatin, M. H. Irrigation, Water Control, Chloride Tolerance and Intrusion
Studies on Rockdale and Perrine Marl Soils of the Homestead Area in 1952. Fla.
Agr. Exp. Sta. Annual Report. p. 331. 1953.
8. Gallatin, M. H. Irrigation, Water Control, Chloride Tolerance and Intrusion
Studies on Rockdale and Perrine Marl Soils of the Homestead Area in 1953. Fla.
Agr. Exp. Sta. Annual Report. p. 295. 1954.
9. Gallatin, M. H. Irrigation, Water Control, Chloride Tolerance and Intrusion
Studies on Rockdale and Perrine Marl Soils of the Homestead Area in 1954. Fla.
Agr. Exp. Sta. Annual Report. p. 319. 1955.
10. Gallatin, M. H., J. K. Ballard, C. B. Evans, H. S. Galsberry, J. J. Hinton,
D. P. Powell E. Truett, W. L. Watts G. C. Wilson, Jr, and R. G. Leighty.
Soil Survey (Detailed Reconnaissance) of Dade County, Florida. U.S.D.A. and
Fla. Agr. Exp. Sta. Series 1947, No. 4. 1958.
11. Malcolm, J. L. Manganese Requirements of Potatoes and Tomatoes on Marl Soils.
Soil Sci. Soc. of Fla. Proc. 14:81-87. 1954.
12. Malcolm, J. L. Nitrogen Experiments with Potatoes and Tomatoes on Marl Soils.
Soil Sci. Soc. of Fla. Proc. 15:91-100. 1955.
13. Malcolm, J. L. Tomato Culture Investigations. Fla. Agr. Exp. Sta. Annual Re-
port. p. 308. 1955.
J. L. Tomato Culture Investigations. Fla. Agr. Exp. Sta. Annual Re-
15. Malcolm, J. L. Marl Soils: A Review. Soil and Crop Sci. Soc. of Fla. Proc.
16. Malcolm, J. L. Phosphorus Experiments with Potatoes on the Perrine Marl.
Soil and Crop Sc.i Soc. of Fla. Proc. 17:216-218. 1957.
17. Malcolm, J. L. Phosphorus Experiments with Tomatoes on Perrine Marl. Soil
and Crop Sci. Soc. of Fla. Proc. 17:219-225. 1957.
18. Skinner, J. J. and R. W. Ruprecht. Fertilizer Experiments with Truck Crops.
Fla. Agr. Exp. Sta. Bul. 218. 1930.
19. Westgate, P. J. Potato Culture Investigations. State Project 28$. Fla.
Agr. Exp. Sta. Annual Report. p. 196. 1946.
20. Westgate, P. J. Tomato Culture Investigations. State Project 286. Fla. Agr.
Exp. Sta. Annual Report. p. 196. 196,