• TABLE OF CONTENTS
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 Front Cover
 Table of Contents
 Introduction
 Experimental plan
 Results
 Discussion
 Summary
 Major results and conclusions
 Literature cited














Title: Beef production, soil and forage analyses, and economic returns from eight pasture programs in north central Florida
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Table of Contents
    Front Cover
        Page 1
    Table of Contents
        Page 2
    Introduction
        Page 3
    Experimental plan
        Page 4
        Page 5
        Page 6
        Page 7
        Page 8
        Page 9
        Page 10
        Page 11
        Page 12
        Page 13
        Page 14
        Page 15
        Page 16
        Page 17
        Page 18
    Results
        Page 19
        Page 20
        Page 21
        Page 22
        Page 23
        Page 24
        Page 25
        Page 26
        Page 27
        Page 28
        Page 29
        Page 30
        Page 31
        Page 32
        Page 33
        Page 34
        Page 35
        Page 36
        Page 37
        Page 38
        Page 39
        Page 40
        Page 41
        Page 42
        Page 43
        Page 44
        Page 45
        Page 46
        Page 47
        Page 48
        Page 49
        Page 50
        Page 51
        Page 52
        Page 53
        Page 54
        Page 55
        Page 56
        Page 57
        Page 58
        Page 59
        Page 60
        Page 61
        Page 62
        Page 63
        Page 64
    Discussion
        Page 65
        Page 66
        Page 67
        Page 68
        Page 69
    Summary
        Page 70
        Page 71
        Page 72
        Page 73
    Major results and conclusions
        Page 74
    Literature cited
        Page 75
        Page 76
Full Text


Bulletin 631 May 1961



UNIVERSITY OF FLORIDA
AGRICULTURAL EXPERIMENT STATIONS
J. R. BECKENBACH, Director
GAINESVILLE, FLORIDA







BEEF PRODUCTION, SOIL AND
FORAGE ANALYSES, AND ECONOMIC
RETURNS FROM EIGHT PASTURE
PROGRAMS IN NORTH CENTRAL
FLORIDA

By
M. KOGER, W. G. BLUE, G. B. KILLINGER, R. E. L. GREENE,
H. C. HARmS, J. M. MYERS, A. C. WAmNICK and N. GAMMON, JR.





TECHNICAL BULLETIN




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















CONTENTS
Page

INTRODUCTION -----................... -- ----------.................... .---........-- 3

EXPERIMENTAL PLAN ----.......---.....--------------- ...-----...-... 4
Experimental Area ..--....-.......---..... --...---- .....--...-.....-- 4
Design of Experiment ....-..... ------......-------........-.....---.. 6
Establishment and Fertilization of Pastures ....------.... --... -..---.---- 7
Forage Sam'pling and Analyses ......--.....------.. -----------..-..-- ...10
Soil Studies ....-........- .......-....- ...-.......-..-....--- ...-..-- ..--- ..... 11
Management of Cattle and Animal Data ........----....--... ..------...--..-. 12
Economic Analysis ......-...---------.....-------.... ---...--...----....13

RESULTS ....---......... ---.. -....... ..... ...... ..........---- .........-...................... 19
Management Experiences with the Various Programs ........-----.............. 19
Cow Weights ....---.. .......--.......------------- ......--....... 22
Reproduction Performance of Cows ....----..-- ...-... ..-.....--.--.-- ....--- 22
Weight and Grade of Calves ...---...---.-....-........ --..........--........ 27
\ Forage Yields --...---- --.... -.... .----....-.....- ....----............ 30
Forage Composition .---.....---......-..----...... .......---........ 34
) Botanical Composition of Pastures -............-....-....-... ...........-.......... 36
Rainfall During Course of Trial --................------..-...... ....-.......-- 38
Soil Analyses and Their Relation to Forage Yields ...........---................. 38
Estimated Costs and Returns ............---- ...----- ...---- --.-.........-- 59

DISCUSSION .....................-....... -....--' . -.......-- 65

SUMMARY ...........--... .........-- ---- ---------.......- ...-- --. --.. -........... -......... 70
Animal Response and Beef Production ....................--.........-......... 71
Soil Studies -----.... ---. ................ --....... ............ 72
Forage Yields and Analyses ...--...-.......-.....---..---...............-- 73
Economic Analyses ................ -- ------------.........-............. 74

MAJOR RESULTS AND CONCLUSIONS .-....----. ............. ----.....---- ..--........ 74

LITERATURE CITED .---........---------..--.. .....................---.. 75










BEEF PRODUCTION, SOIL AND
FORAGE ANALYSES, AND ECONOMIC

RETURNS FROM EIGHT PASTURE
PROGRAMS IN NORTH CENTRAL
FLORIDA

By
M. KOGER, W. G. BLUE, G. B. KILLINGER, R. E. L. GREENE,
H. C. HARRIS, J. M. MYERS, A. C. WARNICK and N. GAMMON, JR. 1

INTRODUCTION
According to recent estimates, beef production in the United
States will need to be increased approximately 15 percent by 1970
if the present per capital supply of beef is maintained. Due to
favorable moisture and undeveloped areas suitable for pasture
production, most of this increase in production likely will occur
in Florida and other Southeastern states. There are some 15
million acres of flatwoods soils in Florida, much of which could be
put into improved pasture if economical production practices are
developed. Already more than 2 million acres have been im-
proved, although there is only limited knowledge of the production
potential of these lands or the fertilization and production prac-
tices which will result in the most economical production of beef.
Consequently, a comprehensive, coordinated study of pasture
programs and breeding systems for beef production on flatwoods
soils of central and north central Florida was initiated at the Beef
Research Unit near Gainesville in 1952. This trial was unique in
that personnel from 5 different departments and the administra-
tion were organized into a coordinating committee to pursue a
comprehensive study of various phases of production, including
those pertaining to animal husbandry, soils, agronomy, agricul-
tural engineering and agricultural economics (see acknowledg-
ments). Another unusual feature of the trial was that the vari-
ous pasture programs were evaluated by grazing with cows and
calves rather than by the usual method of grazing with steers or
clipping of forage. This technique was adopted because most

SKoger, Animal Husbandman; Blue, Associate Soils Biochemist; Killing-
er, Agronomist; Greene, Agricultural Economist; Harris, Agronomist; Myers,
Associate Agricultural Engineer; Warnick, Associate Physiologist; and
Gammon, Soils Chemist.








4 Florida Agricultural Experiment Stations

pastures of necessity must be grazed by cows and calves and pro-
ductivity should be determined for the manner in which most pas-
tures will be utilized.
This bulletin summarizes 5 years' results from the first phase
of this trial. Eight pasture programs designed to represent those
that ranchers might use were evaluated from the standpoint of
beef production from a cow-calf operation, soils analyses, forage
production and composition and an economic analysis of each pro-
gram. Results from the cattle breeding study which incorporated
the animals used to graze the pastures are given also.

EXPERIMENTAL PLAN
EXPERIMENTAL AREA
General Characteristics.-The Beef Research Unit is located
approximately 15 miles northeast of Gainesville on flat, pine land
commonly called "flatwoods." Native vegetation (6) consisted
primarily of longleaf pine (Pinus australis Michx. f.), wiregrass
(Aristida spp. and Sporobolus spp.), saw palmetto (Serenoa re-
pens Bartr. Small), gallberry (Ilex glabra L.), runner oak (Quer-
cus minima Sarg.) and cypress (Taxodium asendens Brongn.)

Figure 1.-Typical scene from virgin area showing native vegetation and
pond in right background.



St . "* P6








Beef Production, Soil and Forage Analyses 5

(Figure 1). Most of the soils in the experimental area are some-
what poorly drained, although soils in the area vary from moder-
ately well drained to very poorly drained.
The area is characterized by numerous shallow cypress ponds
of varying sizes. The soils in these ponds contain an abundance
of organic matter. Organic matter content decreases with dis-
tance from the ponds and elevation. A typical scene from the
Beef Research Unit is shown in Figure 2.
Soil Types.-The major soil type in the area is Leon fine sand.
Small areas of Rutlege fine sand and Plummer fine sand occur
around the edge of ponds and in depressed areas. The slightly
higher areas are occupied by Leon fine sand and small pockets of
Immokalee fine sand and Ona fine sand. The highest or best
drained areas are occupied by Blanton fine sand.
Physical and Chemical Characteristics of Virgin Soil.-The
average organic matter content based on surface samples was 2.25
percent, but there were wide fluctuations resulting from relatively
small differences in elevation and drainage. The Rutlege and
Plummer soils contained as much as 7 to 8 percent organic matter.
The surface horizon of better drained soil had organic matter
content as low as 1 percent.
The average soil pH was 4.9 at the beginning of the experi-
ment, but was variable and inversely correlated with percentage
organic matter (Table 29). The soils with high organic content
had pH values of 4.5 to 4.6, while the pH range of soils with lower
organic content was 5.0 to 5.2.

Figure 2.-Typical scene of improved pasture showing pond areas,
clover forages and elevation differences.








6 Florida Agricultural Experiment Stations

Ammonium acetate extractable nutrients were variable but
were generally low. Average values expressed as pounds per
acre were calcium oxide, 200 pounds; P205, 14 pounds; and K20,
54 pounds.
Total P20s averaged about 140 pounds per acre and was pos-
itively correlated with organic matter content of the soil, as shown
in Table 23.
DESIGN OF EXPERIMENT

The trial was designed to obtain soil, agronomic and animal re-
sponse data from 2 replicates each of 8 different pasture pro-
grams. Three of the programs (1, 2 and 3) were all grass pas-
tures with varying levels of fertilizer application. Three pro-
grams (5, 6 and 7) were grass-clover pastures with two levels of
fertilizer application. Program 6 was planned as an irrigated
grass-clover pasture to be fertilized at the same rate as Program
7. An adequate water supply was not available during much of
the trial, preventing a satisfactory evaluation of irrigation. Pro-
gram 6 may be considered as a replicate of Program 7. In Pro-
gram 4, two-thirds of the area was all grass and one-third was
grass-clover pasture. Program 8 was a combination of 1 acre of
improved grass-clover pasture to 2.5 acres of cut-over pine land
with native vegetation. The annual fertilizer applications, for-
age plants and layout of pastures are shown in Table 1 and Figure
1.

TABLE 1.-TYPE OF FORAGE PLANTS AND FERTILIZATION RATE FOR THE
8 PASTURE PROGRAMS.

Annual Fertilization in
Program* Pounds per Acre
N P,O, | K,O

1. All grass ........ .................... 34 18 18
2. All grass .......... ...-- ..... ....... 68 36 36
3. All grass ............... ..... 120 72 72
4. % All grass .... ..................... 68 36 36
/3 Clover-grass .--............--.. .. 0 72 72
5. Clover-grass .. ...-......-..... .. 0 72 72
6. Clover-grass ...................---- 0 144 144
7. Clover-grass ....-....-.......----- 0 144 144
8. 1 acre clover-grass --........... ... 0 72 72
2.5 acres native .................... 0 0 0

There were 2 replications of each program, making a total of 16 pastures. Each pas-
ture was further sub-divided into 3 smaller pastures to facilitate fertilization, rotational
grazing and winter reserve feed.







Beef Production, Soil and Forage Analyses 7

Each pasture was divided into 3 parts in order to separate
grass species, to facilitate rotational grazing and for accumulation
of forage for winter grazing. The pastures were stocked with
pregnant 2-year-old heifers in September of 1952.

ESTABLISHMENT AND FERTILIZATION OF PASTURES
Preparation of Land and Fertilization for Planting.-Pulpwood
was cut from the areas during the spring and summer of 1951.
Stumps and the remaining timber were removed by bulldozing.
A scattered stand of young trees was left in a 50-foot band on
either side of roadways and lanes for landscaping and shade for
the cattle. The area was then web-plowed at a depth of 6 inches
to kill the palmetto and runner oak. The area was prepared for
planting by repeated discing and dragging until a good seedbed
was formed.
Early in the spring of 1952, 1 ton per acre of finely ground
high calcic limestone was broadcast over all pastures to be planted
to grass. Two tons per acre of limestone were broadcast over the
areas to be planted to grass and clover mixtures.
Minor elements, including copper, manganese and zinc as sul-
fates and boron as borax, were uniformly broadcast over all ex-
perimental pastures at a rate of 15 pounds per acre each of the
sulfates and 7.5 pounds of borax just prior to seeding. Fertilizer
at the rate of 350 pounds per acre of 5-7-5 was also broadcast
ahead of planting on Program 1 and at 600 pounds per acre on
all other programs.
Seeding and Sprigging of Grasses.-Pensacola bahia seeding
started March 14, 1952, and was completed June 7, 1952, as soil
preparation liming and fertilizing progressed. The bahia seed
were sown, covered and packed with a cultipacker seeder. Pas-
tures seeded to bahia in March and April were fully sodded by
mid-July, at which time 200 pounds per acre of bahia seed were
harvested by combine.
Pangolagrass planting was started July 7 and completed July
16, 1952. Fresh cut mature pangola hay was obtained from a
nursery field for planting material. This vegetative material
was broadcast by hand off a truck and immediately cut in with a
disk harrow and packed with a cultipacker. A good stand result-
ed, followed by rapid growth. There were over 4,000 pounds of
dry weight forage per acre by mid-September.
In late August approximately 16 pounds of nitrogen per acre
was applied to Program 1, 44 pounds to Program 3 and 32 pounds






8 Florida Agricultural Experiment Stations

to all other programs. By the end of the second season of the
experiment the pangolagrass in the heavier fertilized grass and
grass-clover pastures had materially decreased in stand. Half
of the pangolagrass was plowed and replanted with Coastal ber-
mudagrass in the summer of 1955, thus leaving one-third of each
program in bahia, pangola and bermuda.
Clover Establishment.-Pastures to be top-seeded with clover
were either mowed and the forage preserved as hay or were
grazed closely by cattle just prior to seeding the clover. The grass
sods were not disturbed and the clover seed were broadcast with-
out benefit of seed cover. All pastures received a uniform applica-
tion of 600 pounds per acre of an 0-12-12 mixture immediately
prior to seeding the clover. Fertilization and seeding were start-
ed October 20 and completed October 29, 1952. A mixture of
clover seed consisting of 1 pound of Ladino, 3 pounds each of No-
lin's Louisiana white, Kenland red and Nolin's red, and 7 pounds
of Hubam, for a total of 17 pounds per acre, was sown. Double
the recommended rate of the appropriate inoculum was applied
to the seed immediately before planting. The clover mixture was
seeded during a favorable moisture and temperature period. An
excellent stand of all clovers resulted, and grazing of the clover
started early in 1953.
Subsequent Fertilization of Pastures.-As noted in Table 14,
rates of mixed fertilizer were 300, 600 or 1,200 pounds of 6-6-6
and 600 or 1,200 pounds of 0-12-12 per acre annually. Starting
in 1953, the 6-6-6 grade of fertilizer was changed to 8-8-8, with
225, 450 and 900 pounds per acre being used each year on the
grass pastures. The 1,200 pound per acre application of 0-12-12
(Programs 6 and 7) and the 900 pounds of 8-8-8 (Program 3)
were split into 2 applications. The 0-12-12 was applied half
in the fall and half in the spring. Application of 8-8-8 was
staggered during the early spring and summer. Nitrogen appli-
cations (ammonium nitrate) to grass pastures also were stagger-
ed to obtain uniform grass production insofar as possible for the
entire season.
Fertilization rates and dates, along with the types of fertilizer
applied, are given in detail for the 1955-56 grazing seasons in
Table 2. Treatments in other years were similar.
Ground limestone was reapplied to each pasture at a 1-ton-
per-acre rate in 1954. In the fall of 1957 lime was again applied
at a rate of 1 ton per acre. During the 5-year period of this ex-
periment the grass and the grass-clover pastures received 3 and
4 tons per acre respectively of ground limestone.









Beef Production, Soil and Forage Analyses 9

TABLE 2.-SAMPLE FERTILIZATION SCHEDULE FOR THE VARIOUS PROGRAMS
PROM OCTOBER 1955 TO SEPTEMBER 1956.

Pasture _Fertilizer Materials
Program Desig- I
Number nation 0-12-12 8-8-8 Amm. Nitrate
SPounds Date Pounds I Date ]Pounds Date

1 6A 1,200 3-5-56 275 8-9-56
6B 1,200 6-26-56 275 2-8-56
6C 1,200 4-5-56 275 8-24-56
12A 1,200 6-26-56 275 2-7-56
12B 1,200 3-5-56 275 8-9-56
12C 1,200 4-5-56 275 8-24-56

2 3A 1,800 3-2-56 400 8-10-56
3B 1,800 4-4-56 400 8-24-56
3C 1,800 6-28-56 400 2-7-56
15A 1,800 3-2-56 400 8-10-56
15B 1,800 6-28-56 400 2-7-56
15C 1,800 4-3-56 400 8-24-56

3 4A 1,200 3-2-56 400 5-1-56
1,200 8-10-56
4B 1,200 4-4-56 400 6-26-56
1,200 8-20-56
4C 1,200 6-15-56 400 2-8-56
1,200 9-4-56
13A 1,200 3-25-56 400 5-1-56
1,200 8-10-56
13B 1,200 4-4-56 400 6-26-56
1,200 8-20-56
13C 1,200 6-15-56 400 2-7-56
1,200 9-4-56
4 7A 2,000 10-7-55
7B 1,500 2-9-56
7C 1,500 8-27-56 350 4-10-56
10A 1,500 2-9-56 350 6-26-56
10B 1,500 8-27-56 350 4-10-56
10C 2,000 10-8-55

5 5A 1,600 9-29-55
5B 1,600 9-29-55
5C 1,600 9-29-55
16A 1,600 10-6-55
16B 1,600 10-6-55
16C 1,600 10-6-55
6 1A 1,200 9-29-55
1,200 2-14-56
1B 1,200 9-29-55
1,200 2-14-56
1C 1,200 9-29-55
1,200 2-14-56
11A 1,200 10-6-55
1,200 2-14-56
11B 1,200 10-6-55
1,200 2-14-56

Continued on next page...








10 Florida Agricultural Experiment Stations

TABLE 2.-CONTINUED.

Pasture _Fertilizer Materials
Program I Desig-
Number I nation 0-12-12 8-8-8 Amm. Nitrate
IPounds l Date Pounds Date [Pounds Date

11C 1,200 10-6-55
1,200 2-14-56
7 2A 1,600 9-29-55
1,600 2-15-56
2B 1,600 9-29-55
1,600 2-15-56
2C 1,600 9-29-55
1,600 2-15-56
14A 1,600 9-30-55
1,600 2-14-56
14B 1,600 9-30-55
1,600 2-14-56
14C 1,600 9-30-55
1,600 2-14-56
8 8A 1,200 10-7-55
8B 1,200 10-7-55
8D 1,200 10-7-55
9A 1,200 10-7-55
9B 1,200 10-7-55
9D 1.200 10-7-55

FORAGE SAMPLING AND ANALYSES
Three cages measuring 5 x 10 x 41/2 feet were placed at ran-
dom in each experimental pasture to protect the forage from
grazing. Herbage samples were collected from these cages for
measuring yield and chemical composition. Each field was divid-
ed into thirds with a caged area in each to represent the forage for
that third of the pasture. Samples were collected by mowing a
3.3 x 10-foot strip within the cage. A similar strip was mowed
outside the cage. The difference in weight of forage between that
harvested inside and outside the protected area was assumed to
be the approximate forage consumed by the cattle. Both hand
plucked and mowed forage were used for chemical analysis. All
forage samples were dried in a 1200F. forced air drier until
weights were near constant, and the yield of oven dry forage per
acre was calculated. Samples were collected from February
through September whenever sufficient vegetation had accumulat-
ed for sampling. Clover was usually blooming vigorously with
occasional ripe seed heads. Harvesting always occurred before
grass was mature.








Beef Production, Soil and Forage Analyses 11

SOIL STUDIES
Sampling Procedure.-Virgin soil was sampled prior to selec-
tion of the program areas. Thereafter the legume-grass pastures
were sampled in the fall prior to fertilizer application and also in
the spring in the case of pastures which received split applications
of fertilizer. Samples were taken from grass pastures before the
spring application of fertilizer.
Soil samples consisted of 10 cores taken from the top 6 inches
of soil within a 30-foot radius of cages used for forage samples.
This gave 9 samples for each program replicate or a total of 18
samples per program.
Soil samples taken in this manner were representative of the
top 6 inches during the early years of the experiment, since the
original lime and fertilizer applications were thoroughly disced
into the soil. However, subsequent lime and fertilizer applications
in the soil surface are known to result in the accumulation of phos-
phate and calcium in the surface inch of soil; hence, the later
analyses for these elements, while representative of the average
condition, do not represent the highly localized distribution of
calcium, pH and phosphorus values that are known to exist under
the conditions of an undisturbed sod. These samples were utilized
for comparisons among soil analytical values, forage yields and
plant nutrient values.
,Soil Analyses.-Soil pH was measured in a 1:2 (volume) soil-
water suspension with a Leeds-Northrup potentiometer and thin-
glass electrode. Solutions for determination of extractable potas-
sium, calcium and phosphorus were obtained from a 4:1 (gravi-
metric) ammonium acetate (pH 4.8) soil equilibrium extract.
Potassium and calcium were determined with the Beckman Model
B flame spectrophotometer, and phosphorus was determined col-
orimetrically (3). A value which closely approximates total phos-
phorus on sandy soils was obtained by dry ashing a 5-gram sample
of soil at 450 C. The silica in the ashed sample was dehydrated
by adding 5N HCI, evaporating to dryness and heating for one-
half hour. The residue was taken up in sufficient 5N HC1 to give
a final volume of 100 ml. of 0.1N HC1, and an aliquot of this solu-
tion was used to determine phosphorus colorimetrically, using
aminonaptholsulfonic acid as the reducing agent. Phosphorus
values obtained by this method on sandy flatwoods soils are very
similar to total phosphorus values obtained by the sodium carbon-
ate fusion procedure-hence the designation "total phosphorus"
throughout this manuscript. Moisture equivalent was determined








12 Florida Agricultural Experiment Stations

according to the procedure outlined by Piper (11), and organic
matter by the method of Walkley and Black and as modified by
Walkley (14).

MANAGEMENT OF CATTLE AND ANIMAL DATA
The cows used for grazing the experimental pastures were
Brahman x native crosses, most of which were 1/2 Brahman, al-
though some animals likely were of 3/4 Brahman breeding. They
were purchased from a large commercial ranch in the Lake Okee-
chobee area and were born in 1950. They were mated to bulls of
4 breeds, including Angus, Brahman, Hereford and Shorthorn.
Two bulls of each breed were used each year. For the most part,
bulls were changed annually in order to avoid confounding the
data due to individuality of sires. The breeding season extended
from March 1 to June 4. A bull was placed in each program and
bulls rotated every 12 days so that each bull was in each program
for one 12-day period. Breed of bulls were sequenced so that the
sire of the calf was easily determined from birth date and breed
characteristics of the calf. This technique resulted in calves of
different breeding being rather uniformly distributed in the differ-
ent programs and permitted keeping a cow on the same program
as long as she was in the experiment. Cows were culled the
second time they failed to conceive. The only other cows removed
from the experiment were a few that were extremely poor pro-
ducers or were of unmanageable temperament. Three cows died
during the course of the trial. Cows similar in breeding and
age to the original experimental cows were maintained on reserve
pastures to replace animals which died or were culled from the
experiment.
Each program was stocked permanently with the number of
cows which, estimated on the basis of the first year's experience,
it would maintain on a year-round basis. This number varied
from 5 to 7 per replicate or a total of 10 to 14 cows per program.
Cows remained on their respective programs throughout the year.
Grass was accumulated during the summer months to be grazed
during the winter, and with the exception of Program 3, the
cattle received all their roughage by grazing. In Program 3,
which was an all-grass program receiving heavy applications of
nitrogen, it was found that enough roughage could not be reserved
without excessive lodging and wastage of roughage through con-
tamination and spoilage. Consequently, during the last 4 years
of the trial, forage in the form of hay or silage was harvested







Beef Production, Soil and Forage Analyses 13

from this program during late summer and fed back to the cows
during the winter months. Any harvested forage in excess of
that needed for winter feed was harvested and credited to the pro-
gram from which it was harvested.
The practice was to manage the cattle on as practical a basis
as possible and for the cows to get as much of their feed as pos-
sible from the pastures. Supplementary feed was given only
when necessary. The first year's experience indicated that cows
on the clover-grass pastures wintered satisfactorily without a sup-
plement. This practice, with only minor exceptions was followed
in all clover-grass pastures throughout the experiment. Cows on
the all-grass pastures were fed from 1.0 to 1.5 pounds per head
daily of 41 percent cottonseed pellets beginning usually about De-
cember 1 and continuing approximately to March 15.
A mineral mix consisting on one-half trace mineralized salt
and one-half steamed bone meal was fed free-choice throughout
the trial.
Calves were weaned about August 20 at an average age of
approximately 7 months. Cows were checked for pregnancy at
this time. Complete production records, including pregnancy at
weaning time, birth data, weights of cows and calves, market
grades and value of calves and seasonal weight changes, were
kept for each individual animal in the trial.
Productivity of each program in terms of beef production was
determined from the carrying capacity, weaning percentage,
weaning weights and value of calves produced in the program.

ECONOMIC ANALYSIS
Costs and returns were estimated for each program. To make
the results applicable to a commercial operation, experimental
data were supplemented with data from other studies. Items of
costs were calculated on the basis of the level of experimental
practices used. Costs of developing and establishing pastures and
performing various maintenance operations were charged at ap-
proximately what they would have cost on a commercial opera-
tion. Income was based on production of beef on each program
and market value of the calves at weaning age.
In calculating costs, no charges were made for irrigation on
Program 6, since it was not possible to irrigate the program as
planned. In the discussion, data are presented on an estimated
cost of irrigating the program, assuming a stated amount of ir-
rigation had been used.







14 Florida Agricultural Experiment Stations

Cost of Establishing Pastures.-Amounts of seed, fertilizer
and lime used in establishing pastures are given in Table 3. Vari-
ous items of cost were charged as follows:

TABLE 3.-SEED, FERTILIZER AND GROUND LIMESTONE USED
PER ACRE IN ESTABLISHING PASTURES.
S I F ilir Clover Seed
Fertilizer I
Pro- Lime- Ni- IBahia I I I
gram Acres stone 5-7- trate Seed I I Ken- I Nolan
No. 5* ] of f Ladino White EHubam land Red
S___ i____ soda __ I Red |_
ton lb. lb. lb. b.l. lb. |b. lb. lb. lb.
1 16 1.00 353 104 13.1 -
2 12 .96 604 204 13.1 -
3 8 1.06 594 266 13.1 -- -
4 10 1.50 610 210 13.1 1.0 3.0 6.0 3.0 3.0
5 8 2.06 594 206 13.1 1.0 3.0 6.8 3.0 3.0
6 6 2.00 558 212 13.1 1.0 3.0 7.0 3.0 1 3.0
7 8 2.00 594 219 13.1 1.0 3.0 6.8 3.0 3,0
8 6 2.08 600 208 13.1 1.0 3.0 7.0 3.0 1 3.0

With minor elements added.

(1) The value placed on land was the estimated market value
of "cut-over" land when the pastures were established. It was as-
sumed a ranch would be fenced with barbed wire. Land was val-
ued at $30 per acre. This amount was assumed to cover value of
the land and cost of fencing the pastures with barbed wire.
(2) Land clearing was charged on a per acre basis at the con-
tract rate paid. Disking, raking, picking up and burning trash
were done by station laborers. The amount charged repre-
sented about 60 percent of actual cost to the Experiment Station
as estimated by one who supervised the operations.
(3) Amounts of lime, fertilizer and seed charged to each pro-
gram were those actually applied. Costs of each of these items
were based on average prices paid by the Experiment Station
(Table 4). Items donated were charged at their market value.
(4) Operations for applying lime and fertilizer and seeding
grass and clover were based on those normally used by commer-
cial operators in establishing permanent pastures. Costs of per-
forming these operations were charged on a per acre basis. The









Beef Production, Soil and Forage Analyses 15

rate for each operation was assumed to cover man labor, power
and use of equipment as reported by Reuss (12).

TABLE 4.-PRICES AND COST RATES USED IN
CALCULATING COSTS OF ESTABLISHING PASTURES.
I I
Item Unit I Price per Unit

Mixed Fertilizer, Ground Limestone and Top Ammonium Nitrate

5-7-5 high level of minor elements,
Program 1 only ........................... ........ ton $66.35
5-7-5 low level of minor elements .............-- ton 52.35
Nitrate of Soda ...-....----............. .. -------........ ton 68.00
Limestone .........-.. .......- ......- ...............I.. ton 4.90*

Seed and Plant Material

Bahia seed .............---.-......... ............... lb. .60
Ladino clover ......-- ..........- ...-......... ........ lb. .85
Hubam clover ...-........... ..... .... ........- .. lb. .15
Kenland red clover ....----.................. .......- lb. .60
Nolin white clover ................... ........I lb 1.10
Nolin red clover ................................... lb. .75
La. white clover ............. ..- ....... ......... ...... lb. .78
Pangola plant material ..............-.......... acre 5.00

Cost Rates for Specified Operations

Stump, pile, web plow and disk ................ acre 35.00
Level, disk, chop, pick up and burn ................ acre 20.00
Disking .---- ............. ---------.............. ------------- acre 2.50
Dragging ...--... ........ acre 1.00
Spreading fertilizer ......--.-------.....--.. ----.-.. ton 5.00
Seeding bahia seed .......... ........ ... ... ....... acre 1.75
Planting pangola stems ........- ................. acre 7.50
Seeding clover seed .............---................. acre .75
Value of land and fence ................... .. acre 30.00

* Price includes cost of spreading.

(5) Costs of planting pastures were charged at what it would
have cost a commercial operator using comparable amounts of
fertilizer and seeding materials. No establishment cost was in-
cluded for planting the Coastal bermuda which replaced half of
the pangola pastures in 1955. It was assumed that if Coastal ber-
muda had been seeded when the pastures were established the ex-
tra costs wQuld not have been necessary.
Annual Costs and Returns.-Estimates were made of annual
costs of maintaining pastures in each program based on the level
of experimental practices used. In addition to these costs, charg-









16 Florida Agricultural Experiment Stations

es were made to cover mineral supplement, supplemental feed,
investment charge and depreciation, breeding fees and other costs
of maintaining the cattle.
(1) Cost of Fertilizer, Topdressing and Limestone.-The
charge to each program for fertilizer and top dressing was based
on the amounts applied (Table 1). Cost per ton was based on the
average price paid for these items (Table 5). Cost per ton for
lime included spreading and was prorated on a yearly basis.

TABLE 5.-PRICES AND COST RATES USED IN CALCULATING
ANNUAL COSTS AND RETURNS.

Item Unit Price per Unit

Mixed Fertilizer, Limestone and Top Ammonium Nitrate

8-8-8 ............---.... --. .--- ....- ---. ... ton $42.59
0-12-12 ......-----......... ------.. --------.. ton 31.56
Lime ......................... ..--- ..-..- ......----... ton 4.90
Ammonium Nitrate ..----................ ....-------.... ton 78.50

Maintenance Operations

Spreading fertilizer -..........------.----. ..-- -----. per ton 5.00
Spreading top dressing ....... ............................. per ton 10.00
Miscellaneous maintenance .-----...............---....... per acre 2.00
Harvesting silage .--......-..-..- :---.-...:--. ---.... -[- per ton 3.00

Investment Charge

Interest on investment ....--........................-- .... per dollar
of investment 5 percent

Feed and Minerals

41 percent cottonseed pellets ...... --............... cwt. $ 3.74
Trace mineralized salt .-......----- ...... ...- cwt. 2.64
Steamed bone meal ....---.....---.....-...... -- ... cwt. 3.93
Silage ............. --------.... ---------.... ....... ton 7.50

Animal Costs

Breeding fees ...................- ....- -........ ....... per cow $ 6.00
Labor on cattle ........---............. ............ ...... per cow 2.00
Vet., med., taxes, etc ......------............ .........- ....... per cow .50
Depreciation on cows ................................-....... per cow 9.00
Interest on livestock inventory .----....................... per cow 6.25
Other ....-..-- --.........- .................. -...... ........ per cow 2.00
Total .-----------.---------..... ........... er cow 25.75







Beef Production, Soil and Forage Analyses 17

(2) Cost of Maintaining Pastures.-Costs for spreading fer-
tilizer were charged on a per ton basis, based on the normal time
on commercial operations (Table 5). The rate charged was as-
sumed to cover labor, power and use of equipment (12). Pastures
received some maintenance such as chopping and mowing each
year. An annual charge of $2 per acre was made to cover such
miscellaneous operations.
(3) Interest on Investment and Depreciation of Pastures.-
It was assumed that annual fertilization and maintenance prac-
tices were adequate to maintain or improve the pastures. There-
fore, the cost of establishing each pasture was not depreciated
over a period of years. An annual interest charge of 5 percent on
the capital invested in establishing each pasture was made to
cover the investment charge.

TABLE 6.-AVERAGE ANNUAL MINERAL AND PROTEIN SUPPLEMENT INTAKE
AND SILAGE HARVESTED FROM VARIOUS PROGRAMS, 1953-57.
Min- I
eral* Cotton Silage Per Acre
In- Seed I Acres
Program take Pellets I Credited Per Cow
Per Per Harvest- Fed to Pro-
Cow Cow ed gram I
lbs. lbs. ton ton ton
1 51 55 -
2 45 73 2.00
3 35 83 1.2 1.1 0.1 1.33
4 31 41 0.8 0.8 1.67
5 25 1.1 1.1 1.33
6 16 1.1 0.3 0.8 1.20
7 27 1.1 0.3 0.8 1.23
8 22 55 .02** 4.00

Consisting of % trace mineralized salt and % steamed bone meal.
** Cows in this program were fed silage for 30 days during 1 year only.

(4) Cost of Feed and Minerals.-A record was kept of supple-
mental feed, salt and bone meal fed the cattle. These items were
charged on the basis of the average annual amount fed on each
program (Table 6). Hay or silage was fed to cattle on some pro-
grams, but in summarizing the data, forage was handled as if
silage were fed. If forage was cut from the program on which it
was fed, a charge was made to cover only cost of harvesting. In







18 Florida Agricultural Experiment Stations

other cases silage was charged at $7.50 per ton. All purchased
feed and minerals were charged at the average annual cost (Table
5).
(5) Annual Charges for Cattle.-To obtain an estimate of
total costs of producing beef, charges were included to cover labor
for caring for the cattle, breeding fee, veterinary expenses, medi-
cations, taxes, depreciation on cows, interest on livestock inven-
tory and other costs. The amount charged for these items was
based on data obtained in a study of improved pastures in central
Florida (Table 5). Cows in the experiment were valued at $125
per head. Five percent was used in calculating interest charge on
the livestock inventory.
Method of Estimating Returns.-In calculating returns, each
program was credited with value of calves produced on the pro-
gram. A credit was also allowed for any forage harvested and
not fed back to cattle on the program and also for growth of tim-
ber on Program 8.
(1) Production of Beef.-Production of beef for each program
was calculated from the average weaning percent, number of cows
on the program and average weaning weight of calves standard-
ized for variables indicated in Table 12. Value of beef produced
was the approximate market value of calves at weaning age based
on live slaughter grades. Prices of beef per pound used in calcu-
lating income were 13 cents for standard, 16 cents for good and
19 cents for choice calves.
(2) Credit for Value of Forage Produced.-Any forage har-
vested and not fed back to cattle on the program from which it
was harvested was credited to the program at a value of $7.50 per
ton for silage.
(3) Credit for Growth of Timber.-Timber growth on the
native area of Program 8 was estimated by members of the For-
estry Department at the rate of four-tenths cord per acre per
year. At $5.00 per cord, the value of timber produced amounted
to $2.00 per acre per year. This amount was credited against the
cost of producing beef in this program.







Beef Production, Soil and Forage Analyses 19

RESULTS

MANAGEMENT EXPERIENCES WITH THE VARIOUS
PROGRAMS
All-Grass Programs.-In the all-grass programs with the low
and intermediate fertilizer applications (Programs 1 and 2) it
was possible by deferred grazing to have an adequate amount of
roughage for the cattle to graze at all times. Quality of roughage
deteriorated rapidly after frost, however, and protein supplement,
at the rate of 1 pound per head daily, was fed in all-grass pastures
for approximately 100 days each year. Whether this supple-
mentation was adequate for all years is problematical, as will be
discussed later in the section on reproduction. Results indicated,
however, that supplementation of frosted grass was necessary to
maintain satisfactory weights and condition in the cows. Pan-
golagrass was the principal forage reserved for winter grazing in
this study.
In Program 3, where the carrying capacity per acre was higher
due to application of a higher level of fertilizer, it was not possible
to keep a constant number of cows on the program throughout
the year. Reservation of enough forage for winter grazing re-
sulted in lodging, smothering of sod and excessive loss of forage
due to trampling and contamination. Thus, after the first year,
approximately 1.5 tons of silage per cow was harvested annually
during the summer months and fed back to the cows during the
winter months after the standing forage had been mostly grazed
off. This method proved satisfactory from the standpoint of
maintaining the cows in good condition, but it increased costs due
to charges for harvesting silage and hauling it back to the cattle.
Clover-Grass Programs.-A satisfactory yearlong grazing pro-
gram was achieved in most of the clover-grass pastures. Less
reserve grass for deferred grazing was required in the clover pro-
grams than in all-grass programs, since clover production pre-
ceeded grass in the spring by approximately 6 weeks. This early
growth of clover, along with clover which lived through the sum-
mer months and provided some legume forage beginning in Oc-
tober, alleviated the need for protein supplement. Cows on the
clover-grass pastures received no supplemental feed and obtained
all their nutrients from the pastures except for 2 pastures where
a small amount of silage was fed during the winter.
In clover pastures, however, only moderate amounts of forage
can be reserved for winter grazing without danger of reducing the







20 Florida Agricultural Experiment Stations

stand of clover. Thus, there was always the danger that adverse
weather conditions would result in a disastrous feed shortage
requiring heavy feeding of the cattle. This is a very real danger,
especially where the stocking rate is high. Consequently, silage
or hay was harvested from these programs and stored for possible
emergency feeding.2 Any silage not fed back was credited to the
program.
Combination Programs.-In Program 4, two-thirds of which
was all-grass and one-third was clover-grass pasture, the cows
were confined to the grass area the first winter in order to es-
tablish the clover area. Thus, during the first year the cattle
responded similarly to those on the grass programs. By the
third year, however, there was considerable live-over clover in
the clover area and noticeable areas of clover were appearing in
the grass portion. Thereafter the cattle responded similarly to
those on programs where clover was planted throughout. Supple-
mental protein was not fed on this program during the last 2
years. From the standpoint of ease of management, supply of
winter feed and performance of cattle (after the first year),
this was one of the better programs.
Program 8 provided only 1 acre of improved clover pasture per
cow, the remainder of the program being native pasture. The
limited clover area necessitated confining the cows to the native
area during a part of winter and spring months to avoid over-
grazing of the clover during this period. While the cattle were
confined to the native area, they were fed protein supplement, and
during 1 year received a limited amount of hay for 30 days. The
native area was not burned during the trial. It was felt that the
large amount of dry roughage provided when unburned was of
more value to the cattle than the limited amount of green feed
that would have been available following burning. The cattle
spent most of their time in the native areas during the winter
months even when they had access to the improved area. Most
of the roughage in the native area was utilized by the cattle by the
time forage became plentiful in the improved portion. During the
summer months the cattle grazed very little in the native area
but used it extensively for shade and as a loafing area. This was
one of the most popular programs with the herdsman because of
ease of management, protection for cattle during cold, rainy

"2During the first winter following this study, extended cold weather
necessitated feeding roughage in all-clover pastures for a period of 20
days.















TABLE 7.-SEASONAL WEIGHTS AND WEIGHT CHANGES IN COWS (POUNDS) BY PROGRAMS.
AVERAGE FOR 5-YEAR PERIOD 1953-1957.

Program Number
Approximate 1 2 3 4 5 6 7 8 Average
date of weighing _

wt. Aug. 15 .................. 887 912 909 1009 918 848 838 894 902 Q
wt. change ....-----.-................. 91 67 96 94 26 40 48 37 62
wt. Nov. 15 ................................ 978 979 1005 1103 944 888 886 931 964
wt. change ...-....-..---........... -153 -171 -184 -231 -126 -134 -125 -142 -158
wt. March 1 ............................. 825 808 821 872 818 754 761 789 806
wt. change ............................ 38 63 87 102 114 86 110 81 85
wt. June 1 .............-- .......... 863 871 908 974 932 840 871 870 891
wt. change ............................... 66 62 25 53 31 34 43 45 45
wt. Oct. 15 ....----------.............. 929 933 933 1027 963 874 914 915 936
Mean Weight .....--..................... 896 901 915 997 915 841 854 880 900
Net wt. change ........................ 42 21 24 18 45 26 76 21 34


CO0





r-








22 Florida Agricultural Experiment Stations

weather and the safety feature of reserve forage in the native
area.
Mineral consumption by the cattle, amount of protein supple-
ment fed and the forage harvested and fed in the various pro-
grams are shown in Table 6.

COW WEIGHTS
All animals were weighed 4 times annually. The first quarter-
ly weight was taken at weaning about August 15; the second, ap-
proximately November 15, when it was estimated that the cattle
had reached their peak weight; the third, March 1, when the
breeding season started; and the fourth, June 1, when the bulls
were removed from the pastures.
The seasonal weight changes (Table 7) showed some interest-
ing differences among programs. Cows in all programs gained
during the quarter following weaning of the calves, lost weight
during the winter quarter during which they calved and gained
weight during the breeding season and from June 1 to weaning
time. In comparing the grass (1, 2, and 3) and clover (5, 6, and
7) programs, however, cows on the former gained more immedi-
ately following weaning and after June 1. Cows on the all-grass
pastures lost significantly more weight from November 15 to
March 1 and gained significantly less weight during the breeding
season. Weight changes of cows on Program 8 (combination of
improved and native pasture) were similar to those on clover pro-
grams. In Program 4 (1/3 clover and 2/ grass) weight loss was
heavy during the winter months but gains were very good during
the breeding season. The possible relation of these differences
to reproductive behavior is discussed in the next section, dealing
with breeding efficiency.

REPRODUCTION PERFORMANCE OF COWS
There was a striking difference in reproduction rate in the var-
ious programs and during different years. Also there was a
marked difference due to lactation status of the cow during the
breeding season. The data are shown in Tables 8 and 9.
A most striking feature was the failure of the nursing cows
on grass pasture to conceive during the first 2 years of the trial.
A total of 50 nursing cows were exposed to bulls on grass pastures
before a single conception occurred. In 1955 the situation began
to improve; 26 percent of the nursing cows on the grass pro-
grams conceived. During the last 2 years of the trial, conception









TABLE 8.-PREGNANCY RATE BY PROGRAM, YEAR AND LACTATION STATUS
OF Cow DURING BREEDING SEASON, 1953-57*.

S_______Program Number_ t_
-Weighted
1 2 3 4 5 6 7 8 Average

Nursing Cows Q

1953 ............................... 0 0 0 0 75 62 50 62 32
1954 ........................ 0 0 0 14 60 38 80 38 32
1955 ..............-........... 33 43 87 100 86 89 100 71
1956 -......................... 100 80 100 83 100 75 90 88
1957 ...................... 91 91 100 100 90 100 100 67 93

Weighted Average .................. 42 48 52 68 82 79 77 71 65

Dry Cows

1953 ................................ ** 100 100
1954 ....... ..................... 100 100 100 100 100 100 100 100 100
1955 ...........-................ 100 100 100 100 100 100 100 100 100
1956 ............................ 100 80 50 82
1957 ................................ - 100 100 100 100

Weighted Average ........... 100 93 92 100 100 100 100o 100 97

Av. mean weaning I
percent for, all cowst ........... 63.1 63.8 66.1 75.8 85.0 82.7 81.8 77.4 74.5

* Pregnancy rate as used .here refers to percent of cows pregnant by palpation at the time calves were weaned about Aug. 20.
** No cows in sub-group.
t Equilibrium frequency = f = wf + (1 f) d where w = pregnancy rate in nursing cows and d = pregnancy rate in dry cows.








24 Flordia Agricultural Experiment Stations

rate on the grass pastures was comparable to that on clover pas-
tures. Clover had begun to invade the grass pastures by the third
year of the trial, however. Whether this was a factor contribu-
ting to the improvement in conception is not known definitely but
it appears likely. Conception rate in dry cows was extremely high
in all programs.

TABLE 9.-VARIANCE ANALYSIS OF PREGNANCY RATE IN NURSING COWSf.

Source df Mean Square

Years -- --..............-.................... 4 1,1074.8**
Program s .......--- ......--..... ....... --7 2,449.9*
Replication ....--- ......--- ..---- ......-- 1 1,312.0*
Y x P .........-...... ----.......-- .. ..... 28 908.2**
Y x R .. -....................- ..-............... 4 273.3
P x R ....................... .................. 7 221.9
Y x P x R ----............................. .. 28 275.6

* P = .05
** P = .01
t Iata were classified by replication, program and year. Percentages were transformed
to angles.

The occurrence of low reproductive efficiency on improved pas-
tures had not been reported previously. Other more recent stu-
dies by Warnick and Koger (15), however, have shown that low
reproductive efficiency in young nursing cows is widespread in
Florida. It was not possible to incorporate detailed studies in this
trial to clarify the problem. Weight data were analyzed for pos-
sible indications, however, and detailed physiological studies were
initiated under supporting project.
The fact that both cow weights (Table 7) and weights of
weanling calves (Table 13) were similar on grass and clover pas-
tures would suggest that the general level of nutrition was not the
principal explanation for the difference in reproduction on these
programs. Seasonal distribution and quality of feed, however,
probably were involved. Cows on grass pastures lost more weight
during the winter months due probably to lower protein content
of roughage (Table 15). They also gained less weight during the
breeding season than cows on clover pastures, where the feed
came earlier, was more abundant and was of higher protein con-
tent. Gain during the breeding season was positively correlated








Beef Production, oil and Forage Analyses 25

with conception rate (gross c relation coefficient = .66). When
gain during the breeding season was adjusted for by covariance
techniques, there was still a significant difference in calving rate
in favor of the clover pastures (Table 10). These results would
indicate that there was possibly some qualitative influence of
clover over and above its effect on weights and gains during the
breeding season. This suggestion is supported by data from de-
tailed studies of breeding efficiency on similar cows under con-
trolled conditions. In these experiments the addition of alfalfa
leaf meal to a ration of pangola hay and cottonseed meal has re-
sulted in reduced postpartum interval to estrus and increased
number of pregnancies in young lactating cows (17).

TABLE 10.-SUMMARY OF COVARIANCE ANALYSIS OF GAIN DURING BREEDING
SEASON (X) AND PREGNANCY RATE OF NURSING COWS (y). POOLED
GRASS AND POOLED CLOVER PROGRAMS CLASSIFIED BY YEAR.

Mean Squares and Products Errors of Estimate
Source df I Mean
_x xy y Idf Square
Pasturet ......... '. 1 6,991 6,001 5,151
Year .-.................. 3 15,304 10,756 9,941
P xy ........... 3 672 640 2,609
Error .........-...... 24 1,247 28 671 23 699

Pasture means adjusted for gain .---...------------........ 1 3,924*
Years adjusted for gain ..................................... --- .... 3 4,955**

t All-grass vs. Clover-grass.
* P = .05
** P .01

Pregnancy rate in nursing cows increased progressively with
years on both grass and clover pastures. In the case of grass
pastures, invasion of clover may have been a contributing factor.
The performance of cows on clover pastures and other observa-
tions, however, indicate there was a time trend over and above
what could be attributed to pasture effects. One factor probably
was increasing age of cows. Pastures were stocked in 1952 with
pregnant 2-year-old heifers. Replacements added during the
course of the trial were of the same age as the cows removed.
Thus, all the cows were approaching their prime in 1956 and 1957.
The tendency for reproduction to be somewhat lower in young
cows, especially under conditions of stress, is generally recognized








26 Florida Agricultural Experiment Stations

by ranchers and has been substantiated by experimental studies
in Florida (15).
The increase in pregnancy rate in all programs, however, was
somewhat larger than that generally thought to be associated
with age of cows. The procedure followed was to cull cows the
second time they were non-pregnant at the end of the breeding
season. It is felt that this practice removed cows with the inclin-
ation to calve on alternate years and had an important bearing on
increasing pregnancy rate to 95 percent during the last year of
the trial.
After the first year's experience of no pregnancies occurring
on grass pastures, the question arose as to whether the difficulty
was due to failure of estrus in the cows or due to failure to con-
ceive when bred. To gain information on this point, bulls were
painted daily on the brisket during the 1954 and 1955 breeding
seasons and the cows checked for paint marks to determine if
mating had occurred. This information, along with calving dates,
was used to calculate interval from calving to first estrus, number
of services per conception and gestation length. The data are
summarized in Table 11.

TABLE 11.-INTERVAL IN DAYS FROM PARTURITION TO FIRST OBSERVED
POST-PARTUM ESTRUS AND SERVICES PER CONCEPTION. 1954-1955.

Interval to Services Per
Program First Estrus Conception
Number No. of Av. INo. of IAv. No. of
cows interval Icows I services

1 ......... ....... .............. 7 98.4 18 1.33
2 .............. ............... 10 94.2 17 1.40
3 .......... .... ................ 9 75.4 15 1.47
4 .................................... 12 75.4 17 1.47
5 .................................. 16 75.9 21 1.19
6 ..-. ........... ......... 16 69.4 20 1.27
7 ................................. 15 66.5 18 1.35
8 .... ....... ..................... 9 76.8 14 1.54

Av., grass programs ........ 26 90.3 50 1.40
Av., clover programs ........ 61 72.5 90 1.34








Beef Production, Soil and Forage Analyses 27

Variance Analysis of Interval to First Estrus

Source df Mean Square

Programs ....-- ----- -... --......-- ..--. 7 588*
Y ear ................................. .................. 1 455
Program x year .....--....------.------------.. 7 297
Grass vs. clover .......-.............................-. 1 5,786**
Error .......... --........--.....- ................... 70 I233

t Differences in services per conception were non-significant.
*P = .05
** P = .01

The cows which were not paint marked were not included, be-
cause not all bulls could be painted. For the cows which were
marked, the number of services per conception was 1.40 for grass
programs and 1.34 for clover programs-a non-significant differ-
ence. These results indicate that the lower pregnancy rate in
cows on grass pastures was due to failure of cows to come into
heat rather than failure to conceive when bred. This indication
was also supported by the length of interval from calving to first
estrus. The average for grass programs was 90.3 days, while that
for clover programs was only 72.5 days. The difference was high-
ly significant. These results are in agreement with those reported
by Witt et al. (17) in which the majority of young cows on pan-
gola hay and cottonseed meal failed to come into heat.

WEIGHT AND GRADE OF CALVES
Due to causes such as failure of some cows to produce calves
and random occurrence of sex of calf and breed of sire, dispro-
portionate numbers of calves of different classifications were pro-
duced in the various programs. The least squares method for
fitting constants for main effects (5) was utilized for analysis
of the data classified by program, replication, year, sex of calf
and month of birth. The mean effect of pasture program on
weight and grade of calves was non-significant, as shown in Table
12.
The average weights and grades of calves, adjusted for the
variables indicated, were used along with weaning percentage to
calculate beef production and income from each program. The
results are summarized in Table 13. Prices used in calculating








28 Florida Agricultural Experiment Stations

TABLE 12.-EFFECT OF PASTURE PROGRAM ON WEIGHT AND GRADE OF
CALVES*.

Weaning Weight Market Grade
Program Deviation Adjusted Deviation I Adjusted
from mean Average from mean Average
lbs. lbs. score score
1 .......... 7.3 417 -.10 9.3
2 .-........ .6 423 -.09 9.3
3 .......... -15.9 408 -.56 8.8
4 .......... +10.8 435 +.04 9.4
5 .......... +18.5 443 +.33 9.7
6 .......... 6.8 417 +.10 9.5
7 .......... 3.1 421 -.07 9.3
8 .......... + 4.3 428 +.38 9.8

The effect of program on weight and grade was non-significant. Thus program influence
was reflected mainly in carrying capacity and reproduction as shown in Table 13.

income were 13 cents per pound for standard, 16 cents for good
and 19 cents for choice calves.
The average adjusted weaning weights of calves varied from
408 pounds in Program 3 to 443 pounds in Program 5. Calves
from clover programs were slightly heavier and graded slightly
higher than those from grass programs. In both grass and clover
programs, calves from the more highly fertilized pastures were
lighter in weight than those from the programs receiving lower
applications of fertilizer. This response probably resulted from
lowered palatability of forage in the more highly fertilized pas-
tures, where contamination from feces and urine was greater due
to higher grazing intensity.
In total weight production and income per cow and per acre,
clover pastures significantly exceeded grass pastures. This was
due to a combination of a higher weaning percentage and slightly
higher weaning weights and grades of calves in the clover pro-
grams.
Program 6 was a highly fertilized clover program that was to
be irrigated. An inadequate supply of irrigation water during
dry periods made it impossible to irrigate the program as plan-
ned. The irrigation water that was applied did not increase pro-
duction per cow or production per acre as compared to the other
clover programs. Slightly more cows per acre were carried on the












TABLE 13.-PRODUCTION PERFORMANCE OF COWS AND INCOME FROM BEEF BY PROGRAMS, 1953-57.
____ ____ ---- ---- i--------,-------------1---- _1_ ___
Program Acres per Average Weaning Beef Production Slaughter Value of Beef**
Number cow Weaning Weight of Per Per Grade of Per Per Per
________ Percent Calves Acre Cow Calves* Pound Acre Cow
No. Pet. lbs. lbs. lbs. Score -
1 ........ 2.67 63.1 417 99 263 9.3 15.30 $15.15 $40.24
Q
2 ........ 2.00 63.8 423 135 270 9.3 15.3 20.66 41.31
3 ........ 1.33 66.1 408 202 270 8.8 14.8 29.90 39.96

4 ........ 1.67 75.8 435 198 330 9.4 15.4 30.49 50.82

5 ....... 1.33 85.0 443 282 377 9.7 15.7 44.27 59.19
6 ........ 1.20 82.7 417 287 345 9.5 15.5 44.49 53.48
7 ....... 1.23 81.8 421 280 344 9.3 15.3 42.84 52.63

8 ........ 4.00t 77.4 428 83 331 9.8 15.8 13.11 52.30
_____________ ___1-------------------------____________
* Score of 8 equal to high standard; 9 to low good; 10 to good, etc.
"* Standard prices assumed in cents per pound: standard calves, 18 cents; good, 16 cents; choice, 19 cents, etc.
t 1.09 acres of improved pasture + 2.91 acres of native pasture.








30 Florida Agricultural Experiment Stations

irrigation pastures, but this was offset by lower weaning weights
of calves from the program.
In Program 8, which consisted of a combination of improved
and native pasture, weaning weights were comparable to the aver-
age of the clover pastures. Reproduction rate was 77.4 percent,
compared to an average of 83.2 percent for the remaining clover
programs. This difference was due mostly to 1 year's results
(1954) when cows in Program 8 were confined to the native area
during part of the breeding season in order to get clover better
established on the improved portion. Assuming that the improv-
ed portion of this program produced at the same rate as the aver-
age of other clover programs, the beef production from the native
area amounted to 8.2 pounds per acre. With beef valued at 15.8
cents per pound, the estimated income per acre from the native
area grazed in conjunction with improved pasture amounted to
$1.30 per acre.
FORAGE YIELDS
Oven dry forage yields for each program, determined from
clipping caged areas, are given in Table 14. Yields varied from
year to year, with 1953 and 1957 averaging somewhat more her-
bage production than 1954, 1955 and 1956.
The stand of grasses (pangola and Pensacola bahia) was ex-
cellent in the first season, with some pangola drying out the sec-
ond and third years in certain programs. Pangola stands remain-
ed good in all low fertility pastures and deteriorated most in those
heavily fertilized. Clover production was best during the first and
last 2 years; the 1954 and 1955 seasons gave somewhat spotted
clover production due to inadequate moisture. The stand of
clover improved steadily throughout the trial.
Because pangolagrass decreased in stand in the heavier fertil-
ized grass pastures and all grass-clover pastures, one-half of the
pangola pastures was plowed during the summer of 1955 and re-
planted to Coastal bermuda. A good to medium stand of bermuda
was in evidence by the late summer of 1955, with good production
recorded in 1956. By midsummer of 1957 the bermuda stand was
poor in some pastures and was being overrun by pangola, Pensa-
cola bahia, maiden cane and watergrass.
Program 1, which received 225 pounds of 8-8-8 (or equiva-
lent) per acre with 16 pounds of nitrogen as a top dressing (Fig-
ure 2), yielded two-thirds to one-half as much forage as Program
2, which received twice as much fertilizer and top dressing. Dur-
ing 1954 and 1955 yields were similar on these 2 programs.








Beef Production, Soil and Forage Analyses 31

Program 3 received 900 pounds of 8-8-8 fertilizer per acre with
48 pounds of nitrogen top dressing (Table 15), or 4 times as much
as Program 1. Yields of forage from Program 3 were appreciably
higher than those from Program 2 and were approximately 2
times higher than yields recorded for Program 1. Programs 1,
2 and 3, all-grass programs, produced maximum forage yields in
1953, the year following establishment, and in 1957, the last year
of the experiment.
Program 4 was a combination type of pasture with one-third of
the area in clover and grass and two-thirds of the area grass.
The grass-clover pasture received 600 pounds per acre of an 0-12-
12 mixture in the fall, while the grass received 450 pounds of an
8-8-8 fertilizer and 32 pounds of nitrogen top dressing during the
spring and summer. The quantity of fertilizer used on the grass-
clover and grass pastures under this program was considered a
normal application capable of supporting and sustaining good
stands and yields of forage. Actual yields of herbage under Pro-
gram 4 were quite similar to those recorded for the heavily fer-
tilized grass pastures under Program 3. The grazing season for
green forage on Program 4 was appreciably longer than for either
Programs 1, 2 or 3 because of the winter clover.
Program 5 was a grass-clover mixed forage fertilized with
600 pounds per acre of an 0-12-12 mixture in the fall of the year.
This rate and fertilizer formulation has proven successful in past
experiments and has been quite generally practiced by farmers
with grass-clover pastures. Forage yields for the 5-year period
were generally excellent, with green grazing available early in
the year and total production equal to the heavily fertilized Pro-
gram 3 at a lesser cost.
Program 6 involved irrigation and double the rate of fertiliza-
tion used in Program 5 with half applied in the fall and the other
half applied early in the year. Because of an inadequate water
supply and lack of sufficient irrigation equipment, it was impos-
sible to follow a satisfactory irrigation pattern. Forage yields
from Program 6 were the highest of any program under study
but were not sufficiently higher to be of economic importance.
Neither the extra rate of fertilization nor the added water mater-
ially affected the production of grass or clover in this program.
Program 7 was the same as Program 6 but without irrigation.
Forage yields of Program 7 and 6 were similar, indicating little
effect from the very limited supplemental irrigation applied dur-
ing the 5-year experiment.






TABLE 14.-FORAGE YIELD SUMMARY 1953-57.

Fertilizer Pounds per Acre I Yield in Pounds per Acre Oven-dry Forage
Program Rep Nitro- I I I Averaget CA
__Mixed I gen* 1953 1954 1955** 1956 1957
1. Grass ............... Rep 1 225# 8-8-8 16# 4,372 3,866 2,513 3,283 4,166 3,922
Rep 2 225# 8-8-8 6,099 4,829 1,810 4,024 6,662 5,404
Ave. 5,236 4,348 2,162 3,654 5,414 4,663
2. Grass ............... Rep 1 450# 8-8-8 32# 7,788 4,189 2,823 5,891 7,074 6,236
Rep 2 450# 8-8-8 9,134 4,188 2,463 6,200 7,229 6,688
Ave. 8,461 4,188 2,643 6,046 7,152 6,462
3. Grass -.............. Rep 1 900# 8-8-8 48# 9,635 8,358 4,280 8,868 9,320 9,045
Rep 2 900# 8-8-8 8,708 7,268 3,380 9,313 7,346 8,159
Ave. 9,172 7,813 3,830 9,090 8,333 8,602
4. % Clover ........ Rep 1 (%) 600# 0-12-12 I- 11,477 4,980 4,060 9,832 8,989 8,820
% Grass ....... Rep 2 (%) 450# 8-8-8 | 32# 9,626 5,174 3,050 7,194 8,707 7,675
Ave. 10,552 5,077 3,555 8,513 8,848 8,248
5. Clover --.......... Rep 1 600 # 0-12-12 7,403 5,215 2,953 10,670 11,515 8,701
Rep 2 600# 0-12-12 9,960 5,338 3,907 10,464 9,480 8,811
Ave. 8,682 5,276 3,430 10,567 10,498 8,756
6. Clover ........... Rep 1 1200# 0-12-12 10,488 7,825 4,037 9,104 10,258 9,419
Rep 2 1200# 0-12-12 11,026 5,927 2,483 8,586 10,496 9,009
Ave. 10,757 6,876 3,260 8,845 10,377 9,214
7. Clover ............. Rep 1 1200# 0-12-12 7,684 6,265 3,087 7,678 11,881 8,377
Rep 2 1200# 0-12-12 11,869 6,955 3,107 11,912 8,258 9,749
Ave. 9,776 6,610 3,097 9,795 10,070 9,063
8. Clover ......... Rep 1 600# 0-12-12 9,552 5,085 3,660 7,656 6,780 7,268
Native ........... Rep 1 1,789 2,699 1,160 2,106 1,940 2,134
Clover .............. Rep 2 600# 0-12-12 9,578 4,364 3,850 7,654 9,858 7,864
Native --.......... Rep 2 1,769 1,918 910 2,956 2,164 2,202
Ave. 2 Reps .... 9,565 4,724 3,755 7,655 8,319 66
Ave. Native .... 1,779 2,308 1,035 2,531 2,052 (2,168)

From ammonium nitrate.
"** Forage yield data low because of Coastal bermuda establishment.
tOmitting 1955 when one-half of Pangola pastures were plowed up and planted to Coastal bermuda.





TABLE 15.-PROTEN AND MINERAL CONTENT IN PERCENT OF HERBAGE CALCULATED ON OVEN-DRY SAND-FREE BASIS.

Nutrient I Program
and Year 1 2 3 4 5 6 7 1 8 *8N

Protein
1953 .... ........ 6.0 7.3 7.2 6.9 8.4 8.6 8.1 8.5 5.3
1954 .................. 6.7 7.5 9.7 8.4 10.7 12.8 10.4 10.7 4.5
1956 ................. 6.2 6.2 7.3 9.1 12.5 12.9 11.5 11.7 4.7
1957 .................. 6.7 6.9 7.8 11.5 17.9 17.6 15.9 15.0 4.8
Ave. .................. 6.4 7.0 8.0 9.0 12.4 13.0 11.5 11.5 4.8

Phosphorus
1953 ................ 0.18 0.20 0.25 0.22 0.24 0.29 0.32 0.22 0.08 0
1954 ................. 0.19 0.22 0.29 0.24 0.23 0.32 0.30 0.24 0.08
1956 ................ 0.21 0.20 0.27 0.26 0.25 0.32 0.28 0.28 0.06
1957 .............. 0.23 0.24 0.26 0.28 0.35 0.40 0.37 0.31 0.19 ;.
Ave. ............. 0.20 0.22 0.27 0.25 0.27 0.33 0.32 0.26 0.10

Potassium
1953 ................. 0.88 1.00 1.19 1.02 1.12 1.35 1.39 1.16 0.33
1954 ...............- 1.13 1.18 1.64 1.33 1.35 2.20 1.86 1.46 0.24
1956 .............. 1.06 1.30 1.25 1.47 1.38 1.65 1.58 1.19 0.30
1957 .............. 1.23 1.21 1.40 1.52 1.91 1.95 2.00 1.56 0.36
Ave. ............. 1.08 1.17 1.37 1.34 1.44 1.79 1.71 1.34 0.31
o
Calcium
1953 ................. 0.30 0.28 0.26 0.40 0.50 0.38 0.36 0.38 0.32 2
1954 .................. 0.26 0.27 0.22 0.32 0.48 0.58 0.45 0.48 0.24
1956 ................ 0.24 0.23 0.20 0.31 0.38 0.35 0.40 0.45 0.19
1957 ................. 0.14 0.16 0.14 0.25 0.46 0.37 0.39 0.46 0.20
Ave. ................. 0.24 0.24 0.20 0.32 0.46 0.42 0.40 0.44 0.24

Magnesium
1953 ............... 0.15 0.17 0.15 0.16 0.19 0.16 0.16 0.18 0.14

Sodium
1953 .................. 0.23 0.26 0.28 0.28 0.32 0.24 0.24 0.32 0.13
1954 ................. 0.24 0.26 0.29 0.18 0.30 0.13 0.18 0.22 0.09
1956 .................. 0.21 0.21 0.24 0.23 0.25 0.18 0.16 0.19 0.10
1957 ........ ....... 0.21 0.20 0.16 0.25 0.32 0.25 0.23 0.23 0.11
Ave. ................ 0.22 0.23 0.24 0.24 0.30 0.20 0.20 0.24 0.11

* 8N = native portion of Program 8.







34 Florida Agricultural Experiment Stations

Program 8 consisted of a grass-clover improved pasture in
combination with native unimproved pasture. Six acres of im-
proved grass-clover were in combination with 16 acres of native
pasture per replication. Fertilization for the grass-clover part
of the program was the same as used in Program 5: that is, 600
pounds per acre of 0-12-12 applied in the fall. Forage yields
were somewhat lower than those recorded from Program 5, prob-
ably due to overgrazing of the clover due to the restricted area.
The native pasture was burned during the year of establishment
of the improved pasture. No other treatment was applied during
the experiment. The native forage yield was one-fourth to one-
third as great as that from the improved area.
All programs with mixed grass-clover forage furnished graz-
ing earlier in the spring and were of higher quality than grass
pastures, particularly in the spring, but also had some advantages
in the fall. Good clover grazing became available during most
seasons by February, with limited grazing in late December and
January. November and December were the 2 months when
clover-grass pastures furnished the least grazing. Grass pastures
did not furnish appreciable new growth for spring grazing until
mid-March and the forage was usually mature by October or
early November. In each program at least one-third of the land
area was allowed to accumulate forage for winter reserve feed
by not grazing the area from August until the feed was needed,
usually in December.
Yields of forage (oven-dry) produced on the 8 programs varied
from 4,663 pounds per acre on the low fertilizer grass treatment
to 9,214 pounds on the heavily fertilized grass-clover area. For-
age yield of replicates of the same treatment varied considerably
during some years. When averaged over the 4- or 5-year period,
however, replicates agreed very well.

FORAGE COMPOSITION
From 1953 through 1957 herbage samples were cut and hand
plucked from all of the experimental pastures to determine yield
and composition. Three caged areas in each pasture were the
source of the mowed samples, while hand plucked samples were
primarily from outside the cage and were vegetation similar to
that being grazed by the cattle. From 5 to 7 samples per cage
were taken each season depending upon growth of the forage,
which in turn was dependent upon rainfall, temperature and time
and rate of fertilization.







Beef Production, Soil and Forage Analyses 35

Samples were oven-dried and all forage yields reported on an
oven-dry basis. Samples analyzed were finely ground and analyz-
ed on moisture-free, sand-free basis. Nitrogen was determined
by the Kjeldahl-Gunning method and crude protein calculated by
using the factor 6.25 times nitrogen. Sodium, calcium and po-
tassium were determined by flame-photometry, and magnesium
and phosphorus by colorimetric methods.
Crude protein is sometimes considered a measure of feed qual-
ity, and on this basis the grass programs 1, 2 and 3 reflect decided
improvement in quality with each fertilizer increment increase.
The clover in one-third of program 4 is directly responsible for
the 9.0 percent protein content, which is higher than any of the
grass plus mineral fertilization programs 1, 2 and 3. Programs
5, 6, 7 and 8, except for the native grass portion of program 8,
reflect a substantial increase in forage protein content due to the
presence of the clover above and beyond that found in the all
grass or two-thirds grass with one-third grass-clover programs.
Phosphorus levels varied from 0.20 to 0.33 percent in the im-
proved grass and legume herbage and averaged 0.10 percent in
the native vegetation. The grass-clover mixed herbage and the
grass fertilized at a high rate averaged 0.25 to 0.33 percent phos-
phorus, which was markedly higher than the forage from the
lower rates of fertilization. Potassium averaged from 1.08 per-
cent for the light fertilization rate on the grass programs to 1.79
percent on the heavy rate on the grass-clover. Native vegetation
averaged only 0.31 percent potassium.
Calcium was appreciably higher in the grass-clover mixtures
than in grass alone, averaging from 0.20 to 0.46 percent. Magne-
sium determinations were made only on samples harvested during
1953 and averaged from 0.15 to 0.19 percent, showing no appreci-
able variation among either forages or rates of fertilization.
Sodium content of the forage was relatively constant, averag-
ing from 0.22 to 0.30 percent for all improved pastures. Native
range contained only 0.11 percent sodium. Pangolagrass had a
much higher sodium content than either bahia or bermudagrass
in the same program.
As would be expected, grass-clover combinations in general
contained the most protein and minerals, with improved grass
second and native vegetation least. Total protein produced per
acre per year is shown in Table 16. The all-grass programs, at
all levels of fertilization, produced forage with less total crude
protein than any of the grass-clover mixed programs. Average
yield of crude protein per acre for the 4-year period varied from








36 Florida Agricultural Experiment Stations

299 pounds for the low fertilization program to 1,193 pounds for
the heavily fertilized, irrigated program. Native vegetation for
the same period averaged only 104 pounds of crude protein per
acre.

TABLE 16.-POUNDS OF CRUDE PROTEIN PER ACRE FROM HERBAGE.

Program No. Year
1953 | 1954 1956 j 1957 Average
1 ................... 314 291 227 363 299
2 .----------.............-----.. 618 314 375 493 450
3 ....-....---..........-...... 670 586 664 650 642
4 ....................... 728 426 775 1,018 737
5 --.....--.-- .---------- 729 565 1,322 1,879 1,124
6 --.........----............... 925 880 1,141 1,826 | 1,193
7 ...................... 792 687 1,126 1,601 1,052
8 .............-....-...---.. 813 505 896 1,248 866
8N* ............... 94 104 119 98 104

* 8N = native portion of Program 8.

BOTANICAL COMPOSITION OF PASTURES
The botanical composition is shown in Table 17 for 1953, the
first year following establishment, and 1957, the last year of the
experiment. These percentages are based on stand and ground
cover estimates at 10 locations in each pasture. A good stand of
grass was noted in all programs at the start of the experiment.
Pangolagrass in particular and some of the bermuda pastures had
deteriorated in the heavily fertilized and clover programs by 1957.
As a result of loss of pangola and Coastal bermuda, considerable
invasion by Pensacola bahia was in evidence. Maiden cane, car-
petgrass and watergrasses also gave serious competition during
the later years of the experiment.
A good stand of clover was obtained in all legume pastures,
with white, Ladino, red and Hubam growing in proportion to
their respective seeding rates the first year. Because of a rather
serious drought in 1955-56, total clover production fell off. Clover
continued to spread through the pastures, however, and the time
during which there was clover for the cattle to graze continued
to lengthen, due to a steady increase of white clover which sur-









TABLE 17.-BOTANICAL COMPOSITION OF EXPERIMENTAL PROGRAMS, MAY 1953 AND AUGUST 1957t.

May 1953 August 1957
Program Rep. I Pensa- *Costal Pensa- Costal
Number Pangola I cola Ber- Clover Other Pangola cola Ber- Clover I Other
______ __________Bahia muda ________- muda- I

1 ........................ 1 100 100 T 90 100 70 5 30
2 100 100 T 100 100 80 T 20

2 ...................... 1 100 100 T 70 90 40 10 60
2 100 100 T 30 100 50 T 70 c

3 ........................ 1 100 100 T 70 100 40 10 60
2 100 100 T 50 100 40 T 60

4** .................... 1 100 100 33 T 50 100 40 55 60
2 100 100 33 T 79 100 50 18 50

5 ....................... 1 100 100 90 T 70 100 40 42 60
2 100 100 100 T 40 100 40 26 60

6 ...................... 1 100 100 100 T 80 100 100 40 20
2 100 100 90 T 10 100 50 35 90

7.......................... 1 100 100 95 T 90 100 20 37 80
2 100 100 100 T 30 100 30 35 70

8 ...................... 1 100 100 80 T 60 100 30 23 70
2 100 100 100 T 50 100 30 27 70

t Values are based on 100 as a complete stand and ground cover.
Coastal Bermuda added 1955 to make each program % pangola, % Coastal bermuda and % Pensacola bahia.
** Program planned for % grass-clover and % grass.
T = trace.
-:1







38 Florida Agricultural Experiment Stations

vived the summer months. During 1957, with rather favorable
rainfall, clover growth was excellent and held up well during the
entire season. By 1954-55 most of the Ladino, red and Hubam
clovers had disappeared. Only a few scattering plants of red and
Hubam clovers were in evidence by the end of the experiment in
1957.

RAINFALL DURING COURSE OF TRIAL
Average annual precipitation at Gainesville 1926-1955 was
51.70 inches. Precipitation during the 1953-1957 period is shown
in Table 18. The 1953 season was abnormally wet, with a total
precipitation of 73.30 inches. On the other hand, 1954 was the
driest year of the period, with only 36.24 inches of rainfall. Pas-
ture production fell off during 1954. However, 9.00 inches of rain
in December of 1953 provided sufficient moisture during the early
spring months to support good clover growth. The total quantity
of forage produced was low for 1954, but the quality of roughage
was as good or better than that of forage produced during sea-
sons of high rainfall. By 1955 the lack of rainfall affected both
clover and grass production adversely. The total 1955 rainfall
was only 44.39 inches. Cypress ponds and areas normally wet
were dry, resulting in sparse clover stands. Again in 1956 rain-
fall was below normal, with only 47.98 inches, but distribution was
good except during November and December, when only traces
of rainfall were recorded. Forage production improved over the
previous 2 seasons. Rainfall was above normal in 1957, with 56.93
inches recorded, and the water table returned to approximately
normal. Forage production was second only to the first year,
1953, with clover growth being excellent throughout the year.

SOIL ANALYSES AND THEIR RELATION TO
FORAGE YIELDS
Nitrogen.-Nitrogen was applied to grass programs only. Part
of the nitrogen was applied in a mixed fertilizer containing N,
P205 and K20 in the ratio of 1 : 1 : 1 and part as a top dressing
of NH4N03. No attempt was made to determine ammonia or ni-
trate in field soil during the course of the experiment because of
the transient nature of these forms of nitrogen.
Laboratory studies were made in 1956 of the relationships
among soil organic matter, total soil nitrogen and nitrifiable soil
nitrogen in samples from different programs. The relationship
between organic matter and total nitrogen was highly significant









TABLE 18.-PRECIPITATION IN INCHES, GAINESVILLE VICINITY 1951-1957.*

__Year

Month 1951 1952 1953 1954 1955 *1956 1957 Average


January .................... 1.07 1.04 4.60 1.16 3.64 3.14 0.59 2.18

February .--..--...- .. 1.05 7.32 1.05 1.40 3.26 4.19 2.37 2.95

March ........................ 5.00 2.33 3.87 2.85 1.66 0.84 5.35 3.13

April .......................... 2.16 3.20 8.43 2.13 1.25 2.78 3.94 3.41

May ............................ 2.31 4.44 2.29 3.32 2.50 4.51 6.69 3.72 ?

June ............................ 3.95 3.31 12.35 3.83 7.04 9.67 7.51 6.81

July ............................ 9.73 3.85 6.71 4.24 11.90 7.24 8.72 7.48

August .-.....-.............. 10.99 3.99 12.78 5.81 5.19 6.81 10.33 7.99
September ................ 7.46 4.66 6.18 5.57 4.04 3.05 6.50 5.35

October ..................... 3.22 4.73 3.37 2.85 1.25 5.57 1.94 3.28

November .................. 6.48 0.88 2.67 1.26 2.51 0.16 2.12 2.30
December .................. 2.55 2.39 9.00 1.82 0.15 0.02 0.87 2.40

Annual ......................-. 55.97 42.14 73.30 36.24 44.39 47.98 56.93 51.00

Data for 1956 and 1957 were collected at the Agronomy Farm. Data for 1951-1955 were from Campus Station, Gainesville. Rainfall data reported
in this table are from stations approximately 6 air miles from BRU.








40 Florida Agricultural Experiment Stations

(r=.91). The regression equation was y=59 + 174x, where
y=ppm total nitrogen and x=-percentage organic matter. Organ-
ic matter and total nitrogen were not significantly correlated with
nitrifiable nitrogen. These data are shown in Table 19. The
effect of lime on the production of nitrate nitrogen in virgin soils
with varying quantities of organic matter was also examined in
the laboratory. These data are shown in Table 20. Nitrate pro-

TABLE 19.-LABORATORY INCUBATION STUDY SHOWING THE RELATIONSHIP
OF NITRIFIABLE NITROGEN* TO PERCENT ORGANIC MATTER AND TOTAL
NITROGEN IN SOIL FROM DIFFERENT PASTURE PROGRAMS.
Total
Organic Soil *NOa N Produced in Each of three
Program Sample Matter Nitro- Successive 14-Day Periods.
gen 1 2 3 Total
Percent p.p.m. p.p.m. p.p.m. p.p.m.
1 ........ 1 1.02 216 10.4 16.3 8.4 35.1
2 2.16 470 28.8 16.0 9.0 53.8
3 2.23 322 7.9 20.9 9.2 38.0
2 ........ 1 2.12 433 11.9 14.4 11.6 37.9
2 2.68 435 6.0 13.9 10.4 30.3
3 4.30 796 16.3 22.2 12.5 51.0
4 4.89 794 7.0 12.6 23.5 43.1
3 ........ 1 2.47 407 25.6 11.8 8.8 46.2
2 2.56 384 21.4 13.7 4.0 39.1
3 3.28 505 11.5 19.4 9.0 39.9
4 ........ 1 1.56 292 19.2 12.5 6.2 37.9
2 2.10 363 22.9 14.3 6.7 43.9
3 3.55 845 29.6 23.3 11.3 64.2
4 4.13 797 22.9 21.5 15.0 59.4
5 ........ 1 2.05 420 25.2 14.4 8.4 48.0
2 2.47 485 13.0 24.5 12.4 49.9
3 3.60 895 9.5 30.8 19.8 I60.1
4 3.91 854 25.6 18.4 13.9 57.9
6 --..... 1 1.37 374 21.5 14.5 8.2 44.2
2 1.93 361 25.6 11.6 7.9 45.1
3 2.32 620 25.1 15.2 11.5 51.8

7 ........ 1 1.51 283 15.0 10.8 9.2 35.0
2 1.64 368 25.7 14.8 11.0 51.5
3 2.84 585 17.6 17.3 19.4 54.3
4 3.10 674 13.0 23.0 14.0 50.0
5 3.50 602 10.6 24.0 9.6 I 44.2
8 --- 1 2.13 398 16.7 14.2 10.6 69.5
2 2.13 617 32.0 15.6 12.4 60.0
3 2.55 423 24.1 11.9 7.3 43.3
4 4.17 695 28.3 20.9 12.1 61.3

Nitrate produced was derived from soil as taken from field. Lime equivalent to 2 tons
per acre was thoroughly mixed with each sample.








Beef Production, Soil and Forage Analyses 41

duction was enhanced by lime, but the incorporation of 1 ton per
acre was about as beneficial as 2 tons. With lime added, nitrate
production was increased as organic matter increased. Without
lime, the rate of nitrification was not significantly higher on the
soils with higher organic matter content. These data, as well as
those in Table 19, indicate that the nitrification rate under field
conditions was adequate when lime was applied.

TABLE 20.-LABORATORY INCUBATION STUDY SHOWING THE RELATIONSHIP
OF NITRIFIABLE NITROGEN* TO PERCENT ORGANIC MATTER, TOTAL
NITROGEN, AND LIME ADDITIONS IN VIRGIN FLATWOOD SOILS.
Total
Lime Organic Soil NO. N Produced in Each of three
Treat- Matter Nitro- Successive 14-Day Periods.
ment gen 1 1 2 1 3 J Total
ton/acre percent p.p.m. p.m. p.p.m. p.P.m. p.p.m.
0 0.94 199 3.8 3.6 12.4 19.8
1 0.94 199 4.3 16.7 5.0 26.0
2 0.94 199 5.8 15.4 6.7 27.9
0 1.26 304 3.8 3.4 9.4 16.6
1 1.26 304 4.1 18.5 10.0 32.6
2 1.26 304 3.6 14.2 9.4 27.2
0 3.33 579 4.3 2.9 9.4 16.6
1 3.33 579 3.1 4.6 26.0 33.7
2 3.33 579 3.8 24.6 14.2 42.6
0 3.48 688 3.4 2.9 7.2 13.5
1 3.48 688 3.6 10.8 27.7 42.1
2 3.48 688 3.8 22.6 27.5 53.9

* Nitrate produced was derived from soil as taken from field.

Relatively large accumulations of nitrate after liming virgin
soils have been measured on several occasions with supplemental
experiments at the Beef Research Unit. The accelerated release
of nitrate following the application of lime probably explains the
excellent growth of newly planted pastures on properly limed flat-
wood soils with relatively small applications of fertilizer nitro-
gen.
In order to take advantage of this accelerated rate of nitrate
production, lime should be applied and mixed with the soil just
prior to planting the grass. Any delay in grass planting may re-
sult in the loss of this extra nitrate stimulation, since nitrates
are readily leached from the soils and plants should be present to
utilize the nitrate as it is produced.
Phosphate.-Ammonium acetate (pH 4.8) extractable phos-
phate was determined annually for both fall and spring soil sam-







42 Florida Agricultural Experiment Stations

ples. Total phosphate was determined for fall samples taken in
1953, 1955 and 1957. Average values for extractable phosphate
are shown in Table 21. The values are averages of 18 separate
samples for each year except 1951. The average of 54 virgin
samples is shown for all programs for 1951.
Data from Programs 1, 2, 3, 5 and 7 were statistically analyzed.
Data from the other programs were omitted because of differences
in treatments within the programs. The increase in extractable
phosphate for these 5 programs for the period was highly signifi-
cant. Differences in extractable phosphate values among pro-
grams also were highly significant. Differences among replica-
tions were significant. The replication x programs interaction
and the years x programs interaction were highly significant.
Five-year average extractable phosphate values for the 5 pro-
grams were closely correlated with quantities of phosphate ap-
plied. The increase in extractable phosphate in fall samples
taken from Programs 1, 2, 3, 5 and 7, calculated by subtract-
ing values obtained in 1953 from those in 1957, was 11, 31,
39 and 62 pounds per acre, respectively. Acid ammonium ace-
tate extractable phosphate decreased with time after phos-
phate application. The decrease apparently was not due entirely
to leaching from the soil. A portion of it was recoverable by the
total phosphorus analytical procedure. In later years of the ex-
periment, phosphate was not applied to all portions of Program
1, 2 and 3 at the same time, but was delayed for some sub pro-
grams to obtain better forage distribution and better forage qual-
ity. This probably caused some variation in extractable phos-
phate values.
Total phosphate values are shown in Table 22. The relatively
small number of samples of virgin soil obtained did not fully rep-
resent each program area, and since there is a close relationship
between organic matter and total phosphate (Table 23), the total
phosphate values for each area at the beginning of the trial were
adjusted in accordance with the organic matter values. Sufficient
soil samples were taken in subsequent years for direct determina-
tion of total phosphate. Analyses were made of Programs 1, 2,
3, 5 and 7 in 1953 and 1955 and all programs in 1957. An increase
in total phosphate occurred in all programs. Essentially all of
the applied phosphate was accounted for in the surface 6-inch
layer from Programs 1 and 2. Only about one-third was account-
ed for in Programs 3 and 5. In Programs 6 and 7 about one-fourth










TABLE 21.-LEVEL OF AMMONIUM ACETATE (pH 4.8) EXTRACTABLE P205 IN SOIL.
Annual
Program Forage Fertilization _P__ Level _
_Plants N P20 KO2 1951 1953 1954 1 1955 I 1956 ] 1957 Ave.
Pounds per Acre Pounds per Acre r
1 ......................... Grass 34 18 18 14 11 8 15 10 25 14
2 ......................... Grass 68 36 36 14 17 15 20 13 45 22
3 .............................. Grass 120- 72 72 14 29 29 34 32 53 35
5 ......................... Clover-grass 0 72 72 14 16 12 18 15 27 18
7 ....................... Clover-grass 0 144 144 14 31 22 46 41 76 43
Ave ......----..........--- - 14 15 17 27 22 45 25
4 ............................. Grass 68 36 36 14 13 13 28 16 45
4a ........................... Clover-grass 0 72 72 14 16 19 43 34 36
6 ........................... Clover-grass 0 144 144 14 28 29 52 64 100
8 ............................ Clover-grass 0 72 72 14 23 17 14 19 30
8 ................................ Virgin None 14 8 5 4 8


Statistical significance of differences for Programs 1, 2, 3, 5 and 7.
Probability of
Source of Variance I Significance

Years .01
Program .01
Replication .05
Replication x Programs .01
Years x Programs .01











TABLE 22.-TOTAL PHOSPHATE APPLIED THROUGH YEAR INDICATED AND TOTAL PHOSPHATE (Pa05) FOUND IN SOILS.

Program 1951 __ 1953 _1955 1957
S*Determ'ned Applied ] Determined t Applied | Determined | Applied I Determined
lbs/A Ibs/A lbs/A lbs/A lbs/A lbs/A Ilbs/A
5-X
1....... 125 39 137 75 174 111 294 2.
2 ..... 152 78 164 150 235 222 444
3 ........ 140 156 249 400 308 544 439
4 ....... 146 78 150 222 352

4a..... 153 156 400 544 451
5 ....... 149 156 193 400 248 544 444
6 ..... 118 228 516 804 450
7 ........ 140 228 181 516 255 804 477

8 ... 150 156 400 544 503
Average of treatments
1, 2, 3, 5 & 7
141 185 255 420

* Because of limited samplings total organic matter was used as a basis for adjusting values reported on 1951 virgin soil samples.








Beef Production, Soil and Forage Analyses 45

of the applied phosphate was found in the surface soil. In con-
sidering these data, the attention of the reader is again called to
the problem of localized differences in calcium, pH and phosphate
which may develop in an undisturbed sod but which must of
necessity be expressed here only in terms of average values. The
values obtained are in general agreement with data published by
Neller et al. (9).
Regression analyses of total phosphate on percentage soil or-
ganic matter are shown in Table 23. This relationship was highly
significant for 1953 and 1957 as well as for virgin samples, and
was significant in 1955. While total phosphate averages for pro-
grams closely paralled quantities of phosphate applied, phosphate
accumulation was to some extent dependent on the organic matter
content of the soil. Since extractable and total phosphate increas-
ed with increasing rates of applied phosphate, it is likely that
these values were related to the quantities of phosphate applied.
The establishment of the relationship between extractable phos-
phate and total phosphate within programs seemed to be very im-
portant because of the variability of soil and phosphate within
programs. Regression analyses of extractable phosphate on total
phosphate were made for 1953, 1955 and 1957 for Programs 1, 2
and 3. While regression coefficients (8) were usually negative,
this relationship was in no case significant. If the decrease in
extractable phosphate with time after phosphate application and
other interrelated factors is considered, the lack of significance
between extractable and total phosphate within programs is not
particularly surprising.

TABLE 23.-RELATIONSHIP BETWEEN ORGANIC MATTER (X) AND TOTAL
PHOSPHATE (Y)
I Regression I Correlation I Degrees of
Year I Intercept Coefficient Coefficient Freedom
1951 .......-............ 61.9 35.3 0.73** 52
1953 .......................... 101.8 35.8 0.35** 88
1955 ...--... -----.. ... 177.7 31.0 0.23* 88
1957 ................---......... 249.1 60.8 0.42** 142

* P = .05
** P = .01

There has been considerable interest in determining relation-
ships between extractable nutrients and crop yields. An exam-







46 Florida Agricultural Experiment Stations

nation of the data showed that extractable phosphate and forage
yields increased with increasing quantities of applied phosphate.
Therefore, the relationship between extractable phosphate and
forage yields was determined for Programs 1, 2 and 3 in a com-
bined analysis. Results of this analysis are shown in Table 24.
The positive relationship shown probably has limited importance,
since N, P205 and K20 were applied in a ratio of approximately
2:1:1 in all 3 programs. Differential response was probably due
to nitrogen rather than phosphate. With these programs it is im-
possible to differentiate among the 3 nutrients, since they were
all increased in the same ratio.
The regression of forage yields on extractable phosphate on a
within program basis was determined for Programs 1, 2, 3, 5 and
7 for each year separately and for combined years 1953 through
1957. In no case was there any consistent relationship.
This lack of correlation between yields and extractable phos-
phate contents is in accord with data obtained by Neller et al.
(9). They found that flatwood soils containing about 20 pounds
per acre of sodium acetate (pH 4.8) extractable phosphate in the
surface 3 inches were borderline in response from applied phos-
phate. Soils containing 30 pounds extractable phosphate per
acre in the surface 3 inches did not respond to applied phosphate.
Soil analyses reported in the present study were from the surface
6 inches of soil. Since phosphate was surface applied, the surface
3 inches of soil should have higher concentrations than the sur-
face 6 inches. Numerous phosphate values, even at low rates of
applied phosphate, were in excess of values given by Neller.
Potash.-Forage yields per pound of potash applied for Pro-
grams 1, 2, 3, 5 and 7 for each year of the experiment are shown
in Table 25. The increasing forage yields with increasing rates
of potash application in Programs 1, 2 and 3 have been previously
discussed and probably are not related directly to potash applica-
tions. The yield per pound of potash applied in Program 5 was
very high. Since no appreciable increase in yield was obtained for
Program 7 over 5, it can be concluded that approximately 72
pounds of fall-applied potash per acre was sufficient for maximum
yields of clover-grass forage under grazing conditions such as
those employed. The removal, of forage for hay, silage or other
purposes would necessitate much larger fertilizer applications
for maximum yields. It would appear that efficiency of cattle ex-
crement in returning and distributing plant nutrients to the soil
has been underestimated.









TABLE 24.-REGRESSION OF FORAGE YIELDS ON NHIAc (pH 4.8) EXTRACTABLE PaOs FOR PROGRAMS 1, 2 AND 3 COMBINED.

Yield during Current YearT Yield during Subsequent Year$
Grouping of Data I Number of Number of
a b r Comparisons a b r Comparisons

By variety of forage
with years combined.

Bahiagrass ................ 2,683 64 .55** 90 2,393 89 .61** 72

Pangola and Coastalt 6,932 41 .23* 72 6,746 16 .11 54

Pangolagrass ............ 5,665 59 .38** 90 6,321 92 .40** 72

By years with varieties .
combined.

1953 ............................ 5,783 104 .27* 54 3,727 103 .37** 54

1954 ..-...................-..---.. 4,260 60 .25 54 3,128 32 .14 54

1955 .................... 2,044 76 .46** 54 4,302 87 .37** 54

1956 ............................. 4,500 80 .36** 54 5,972 50 .26* 54

1957 ....................... 5,745 30 .26* 54

Average all years. ........ 4,810 49 .34* 270 4,245 69 .28** 216

t 1955 data omitted because of replanting to Coastal bermudagrass.
Sa = the mean of the forage yield values in Ibs. per acre.
b = the average increase in yield per Ib. P,O, extracted.
r = the correlation coefficient.
*P = .05
"**P = .01











TABLE 25.-AMMoNIUM ACETATE EXTRACTABLE POTASH IN SOIL BY PROGRAM AND YEARS*.
Annual
Program Forage Fertilization Soil KsO
Plants N POs5 K0s 1953 1954 1955 1956 1957 Ave.
Pounds per Acre Pounds per Acre I
1 ......................... Grass 34 18 18 26 31 33 41 52 37
2 ............................. Grass 68 36 36 40 33 40 54 64 46
3 ........................... Grass 120 72 72 48 59 63 59 70 60
5 ..-----------...........--- Clover-grass 0 72 72 37 52 37 60 60 49
7 .............................. Clover-grass 0- 144 144 53 54 56 76 110 70 .
Ave ........................ 41 46 46 58 71 52
4 ............................. Grass 68 36 36 40 34 35 33 83 45
4a ......................-..... Clover-grass 0 72 72 37 40 38 61 76 50
6 .........-................... Clover-grass 0 144 144 40 52 35 46 68 48
8 .............................. Clover-grass 0 72 72 52 31 39 39 61 44
8 .............................. Native None 20 22 15 33 23


Statistical significance of differences for programs 1, 2, 3, 5 and 7.
S Probability of
Source of Variance I Significance

Years .01
Programs .01
Replications .01 o
Replications x Programs .01
Years x Programs .01
The average K.0 level in virgin soil in 191 before fertilization was 4 pounds er are.
* The average KoO level in virgin soil in 1951 before fertilization was 54 pounds per acre.








Beef Production, Soil and Forage Analyses 49

Ammonium acetate (pH 4.8) extractable soil potash was de-
termined annually on fall and spring samples. The data for fall
samples are shown in Table 25. Values for Programs 1, 2, 3, 5
and 7 for 1953 through 1957 were statistically analyzed. The in-
crease in soil potash concentrations by years was highly signifi-
cant. Differences in accumulation from treatments were also
highly significant. Potash concentrations for years appeared to
be somewhat dependent on rainfall. The average increase from
1951 to 1957 for Programs 1, 2, 3, 5 and 7 were 0, 10, 16, 6 and 56
pounds per acre, respectively. These values, in comparison with
phosphate accumulation, are small. However, the residual potash
is undoubtedly of value for future production. It does not appear
that any appreciable reserve of potash can be accumulated in Leon
fine sand and related soils. Differences in potash concentrations
by replications were highly significant, as were replications x
programs and years x programs interactions.
The relationships between yields and applied potash were sta-
tistically significant for Programs 1, 2 and 3 combined (Table 26).
The previous discussion concerning phosphate and yield as related
to ratios and response to nitrogen is equally applicable for potash.
A significant correlation of forage yields with potash concen-
trations within programs would be of more value than correlation
among programs and would establish the value of extractable
potash in predicting yields. Regression analyses were made for
Programs 1, 2, 3, 5 and 7 individually. All forages were combined
in 1 group of analyses and each grass was considered separately
in other analyses. Potash concentrations were compared with
yields obtained the same year that soil samples were taken and
with yields obtained during the subsequent year. There were no
significant relationships between extractable potash and yields
within programs.
The retention of potash in the surface soil during the 4- to 5-
month winter season has been interesting and very important in
determining the need for supplemental potash in the spring for
optimum clover production. A statistical analysis of potash con-
centrations in soil samples collected in the fall and spring of each
year from Programs 5 and 7 was made. These data are recorded
in Table 27. Seventy-two pounds of potash per acre were applied
to both programs in the fall and an additional 72 pounds to Pro-
gram 7 in the spring. Differences in yearly average concentra-
tions were highly significant. These differences were undoubtedly
related to rainfall and also to the amount of clover growth be-
tween October and about February. Rainfall varied from a low of









TABLE 26.-THE REGRESSION OF FORAGE YIELDS ON SOIL KaO FOR PROGRAMS 1, 2 AND 3.

Yield during Current Year$ I Yield during Subsequent Year$
Grouping of Data I Number of I I] Number of
I a b [ r Comparisons a b r r Comparisons

By variety of forage
with years combined.

Bahiagrass ............... 3,645 15 .22* 90 3,204 26 .40** 72

Pangola and Coastalt 6,205 34 .24* 72 6,746 16 .11 54

Pangolagrass ............ 5,478 34 .28* 90 6,321 4 .03 72

By years with varieties
combined.

1953 ..........-- ............... 4,150 88 .40** 54 3,509 51 .30* 54

1954 -...........-...- 4,705 22 .13 54 2,747 31 .19 1 54

1955 ......................... 1,567 50 .54** 54 5,161 25 .19 54

1956 .....- .............. 6,109 3 .03 54 7,927 -19 -.23 54

1957 ....................... 8,799 -30 -.26* 54 -

Average all years. ........ 5,114 19 .15* 270 4,835 19 .15 216

t 1955 data omitted because of replanting to Coastal bermudagross.
Sa = the mean of the forage yield values in pounds per acre.
b = the average increase (decrease) in yield per pound K,O extracted.
r = the correlation coefficient.
*P = .05
** P = .01








Beef Production, Soil and Forage Analyses 51

1 inch to a high of 15 inches during this period. The difference in
average concentrations between Programs 5 and 7 was highly
significant. Differences among replications and the programs x
sampling date interactions also were highly significant. The dif-
ference between sampling dates was highly significant and is the
most important statistic of the group.

TABLE 27.-POUNDS PER ACRE OF AMMONIUM ACETATE EXTRACTABLE
POTASH IN SOIL FROM PROGRAMS 5 AND 7.
Program [ Yearly
Sampling Dates 5 7 I Average Average

10/53 ......................-... 37 53 45
2/54 .......................... 64 124 94 69
10/54 ...........--............- 52 54 53
2/55 ..........-............... 101 158 130 91
10/55 ......................... -37 56 47
2/56 ........---............. 85 119 102 76
10/56 .-....---...-- ........... 60 76 68
2/57 --......................... 127 228 178 123
Fall Average .................... 47 61 54 -
Spring Average ............. 94 158 126 -
Program Average .......... 71 109 -

Statistical significance of differences
Probability of
Source of Variance Significance

Years .01
Programs .01
Sampling Dates .01
Programs x Sampling Dates .01
Replications .01


Averages for the different years show considerable variation
in retention of potash, probably as a result of differential rain-
fall. The percentages of potash retained for the 4 comparisons
were 68, 107, 76 and 153. Rainfall during the winter season for
the 4 comparisons was 14.9, 11.3, 7.4 and 1.2 inches, respectively.
The overall percentage retention according to these data was 100.
The actual retention efficiency would be somewhat less, but a








52 Florida Agricultural Experiment Stations

number of factors, including fertilizer distribution and potash
held in living plant tissue, present errors in determination. It is
sufficient to say that retention was efficient during this period.
This undoubtedly is 1 reason for lack of response to additional
potash used in Program 7 as compared to Program 5. It would
appear that spring applied potash, supplementing a fall applica-
tion of about 70 to 80 pounds, would be beneficial and economical
only in very unusual years with this soil. The rate of potash
leaching is much more rapid from deep, course textured, ridge
sands. Data from this study probably will not apply to those
soils. Irrigation also might alter retention considerably.
pH and Calcium.-After the original lime treatments it was
found that these rates were insufficient; consequently, the le-
gume-grass programs were relimed at 1 ton per acre in July 1954.
The grass programs were relimed at the same rate in March 1955.
Additional lime was applied in the summer of 1957; this was pri-
marily for the second phase of the experiment.
Data for pH values by years and programs are shown in Table
28. pH values from Programs 1, 2 and 3 were compared by sta-
tistical analysis, as were values from Programs 5, 6 and 7. The
analysis of Programs 1, 2 and 3 showed that differences due to
years, programs and replications were highly significant. The in-
teractions for replication x years, replication x programs and
years x programs were also highly significant. For these pro-
grams the pH values from the initial 1-ton application reached a
maximum of 5.3 and declined in the fall of 1954 to values as low
as 4.9. There was a highly significant negative relationship be-
tween pH and percentage of organic matter in all years except
1953 (Table 29). Program 2 averaged considerably higher in or-
ganic matter; and while this program had the highest calcium
content of the 3 programs, the pH remained closer to Program 3
than to Program 1. This may be explained by the close relation-
ship between organic matter and exchange capacity in this soil,
and the relationship between pH and percentage base saturation.
Differences in pH values for Programs 5, 6 and 7 were highly
significant for years, programs, replications and the years x pro-
grams interaction. pH values were again influenced by organic
matter. The higher values for Program 6 were due to low organic
matter and also calcium in the irrigation water. Calcium values
in Program 6 were maintained at a slightly higher level and the
pH was consistently 6 or above, compared with a pH range of 5.4
to 5.7 for Programs 5 and 7. Calcium analysis of the irrigation
water showed a concentration of about 15 ppm. The contribution








TABLE 28.-pH OF SOIL BY PROGRAM AND YEARS*.

Annual I
Programs** Forage Fertilization _pH
Plants N P205 K20 1953 1954 1955 1956 1957 Ave.
Pounds/Acre :

1 ......- ........... Grass 34 18 18 5.3 5.3 5.7 5.7 5.7 5.5
2 ...................... Grass 68 36 36 5.3 4.9 5.4 5.3 5.3 5.2
3 .............................. Grass 120 72 72 5.3 4.9 5.0 5.1 5.5 5.2
Ave. ........................ 5.3 5.0 5.4 5.4 5.5 5.3
5 .............................. Clover-grass 0 72 72 5.4 5.4 5.4 5.4 5.3 5.4
6 ........................ Clover-grass 0 144 144 6.2 6.0 6.1 6.1 5.8 6.0 0
7 .............................. Clover-grass 0 144 144 5.7 5.6 5.7 5.6 5.5 5.6
Ave. ....................... 5.8 5.7 5.7 5.7 5.5 5.7
4 .......................... Grass 68 36 36 5.7 5.4 5.8 5.9 5.8 5.7
4a .......................... Clover-grass 0 72 72 5.8 5.7 5.8 5.8 5.5 5.7
8 ............................ Clover-grass 0 72 72 5.7 5.6 5.6 5.8 5.6 5.7
8 ............................ Native None 5.4 5.0 5.0 4.9 5.1


Statistical Significance

For Programs 1, 2 and 3 For Programs 5, 6 and 7
Probability of Probability of
Source of Variance Significance Source of Variance Significance

Years ........ ....................... ............................ .01 Years ....................... ............. ...... ...... .01
Program ................................. ..................... .01 Program ................ ......................... .01
Replication ........................... ........... .... .01 Replication ........................................ .01 v,
Replication x Years ....................... .......... .01 Replication x Program ...................... .01
Replication x Program .................................. .01
Years x Program ............................................
The average pH of virgin soil in 1951 before fertilization was 4.9.
** All clover areas limed at 2 tons per acre and grass areas at 1 ton per acre in 1951. Clover areas relimed at 1 ton per acre in July 1954; grass areas 1
relimed at 1 ton per acre in March 1955. C








54 Florida Agricultural Experiment Stations

of irrigation water in maintaining pH, with possible detrimental
effects, is shown clearly by a supplemental irrigation experiment
conducted as Project 684 by the Departments of Agricultural En-
gineering and Soils3. In this study irrigation consisted of 0, 15
and 30 acre-inches of water per year. pH values after 3 years,
where only phosphate and potash were used for the 3 irrigation
treatments, were 6.7, 7.1 and 7.2, respectively. When nitrogen
was included at relatively high rates, the values were 6.5, 6.9
and 7.2, respectively. The increase in calcium was about 300
pounds per acre in the surface soil. The high pH values main-
tained by the irrigation water, even with high rates of nitrogen
fertilization, indicated that the effects of irrigation water should
be followed closely. High pH can be detrimental from the stand-
point of minor element availability.

TABLE 29.-THE RELATIONSHIP BETWEEN ORGANIC MATTER CONTENT OF
SOIL AND pH WITHIN YEARS.
SNumber
Year atS I rb 4 Comparisons

1951 ...........- 5.18 -0.12 -0.50** 54
1953 .........-... 5.60 -0.13 -0.58** 54
1955 ...-.......... 5.44 -0.05 -0.21 54
1957 ---..... 5.10 -0.21 -0.68** 54

t The 1951 samples were from virgin area; remaining samples were from Programs 1, 2
and 3 during the years shown.
Sa = the mean of the soil pH values.
b = the average change in pH per percent organic matter.
r = the correlation coefficient.
"**P = .01

Regression analyses of forage yields and soil pH were made.
Analyses for Programs 1, 2, 3, 5 and 7 were made separately and
for Programs 1, 2 and 3 combined. pH values were compared
with all forages combined and for each of the 3 grass forages sep-
arately. Comparisons were made also with forage yields obtained
during the same year soil samples were taken, and with those
from the subsequent year. There were no consistent significant
relationships within programs. This is somewhat surprising for
Programs 5 and 7 in view of the relatively close relationship of
pH to clover growth. Again keeping in mind the large local pH
variations that will develop in liming an undisturbed sod, it is

I Conducted cooperatively by J. S. Norton and J. M. Myers, Department
of Agricultural Engineering, and L. C. Hammond and W. G. Blue, Depart-
ment of Soils.










TABLE 30.-AMMONIUM ACETATE EXTRACTABLE CALCIUM IN SOIL FROM BEEF RESEARCH UNIT*.
Annual
Program Forage Fertilization Ca (lbs./acre)
Plants N P205 K2O 1953 1954 1955 | 1956 1957 Ave.

1 ............................. Grass 34 18 18 520 550 840 700 1,110 750
2 .......................... Grass 68 36 36 710 750 1,070 860 1,420 960 I
3 ........................... Grass 120 72 72 690 720 920 700 1,190 840
Ave. ................ 640 670 940 760 1,240 850 P.
5 ............................ Clover-grass 0 72 72 740 1,050 870 840 1,060 910
6 .......................... Clover-grass 0 144 144 1,120 1,200 1,190 1,020 1,180 1,140
7 ......................... Clover-grass 0 144 144 1,060 1,190 1,280 880 1,060 1,090
Ave. ...................... 970 1,150 1,110 910 1,100 1,050
4 ............................ Grass 68 36 36 670 720 1,190 730 1,190 900 C
4a .......................... Clover-grass 0 72 72 1,500 1,770 1,590 1,260 1,460 1,516 0.
8 ........................... Clover-grass 0 72 72 1,220 1,480 880 960 1,450 1,198
8 ..-.......................... Virgin None 90 130 90 120 108


Statistical Significance
For Programs 1, 2 and 3 _For Programs 5, 6 and 7
Probability of Probability of
Source of Variance Significance Source of Variance Significance

Years ............. .................... .... ............ .01 Years .. ............. .................. .01
Program s ................... ....... ...... ........ .01 Program s ................................ ............ .01
Replications ...... .................. ...... ...--- ----...- .01 Replications ................ ................... .01
Replications x Programs .........--.-----..... ......- .01 Years x Programs ............................ .01
I Replications x Programs ................... .01

Averages for 5 years after fertilization was begun. The average level of calcium in virgin soil in 1951 before fertilization was 200 pounds per acre.
CT
Um








56 Florida Agricultural Experiment Stations

evident that clover will grow satisfactorily in soils sampled to a
depth of 6 inches which show an average pH of 5.1 to 6.0 as found
in these programs. There was a highly significant negative corre-
lation between yields of Pensacola bahiagrass and soil pH for
the combination of Programs 1, 2 and 3. This undoubtedly re-
flected the increase in yields from increasing rates of nitrogen and
the subsequent depression of pH resulting from acidity produced.
This relationship was not significant for pangolagrass and Coas-
tal bermudagrass.
Ammonium acetate (pH 4.8) extractable calcium values ob-
tained during the course of the experiment are shown in Table
30. Separate statistical analyses were made for calcium values
for Programs 1, 2 and 3, and for Programs 5, 6 and 7, because
a different amount of lime was applied to each group. The analy-
sis for Programs 1, 2 and 3 showed highly significant differences
due to years, programs, replications and the replication x program
interaction. Calcium values were not directly related to pH, due
to the complication of organic matter differentials.
The statistical analyses for extractable calcium values from
Programs 5, 6 and 7 showed highly significant differences due to
years, programs, replications, the replication x programs inter-
action and the year x programs interaction.
Analyses were made also for the regression of pH on percen-
tage soil organic matter for samples from Programs 1, 2 and 3 for
1953, 1955 and 1957, as well as for virgin samples taken in 1951.
These 2 measurements were negatively correlated in 1953 and
1957 and for virgin samples taken in 1951. The negative rela-
tionship was maintained in 1955 but was just under statistical
significance. The fact that this relationship was significant is
interesting in view of the effect of differential fertilizer applica-
tions, lime additions and changes in organic matter content with
years.
Organic Matter.-Soil organic matter contents are shown in
Table 31. Organic matter determinations were made for virgin
soil samples taken in 1951 and for the alternate years 1953, 1955
and 1957. The average organic matter content at the beginning
of the experiment was different among programs. Averages for
program replications were also different in some cases. Soil or-
ganic matter was variable within all programs throughout the
experiment.
A statistical analysis was made of organic matter contents of
samples obtained in 1953, 1955 and 1957. Differences due to
years were highly significant. The average soil organic matter











TABLE 31.-ORGANIC MATTER CONTENT BY YEARS AND PASTURE PROGRAMS.
Annual
Programs Forage Fertilization Organic Matter
_Plants N P2Oc K20 1951* 1953 1 1955 1957
Pounds per Acre Percent Percent Percent Percent

1 ............... ............ ..... Grass 34 18 18 1.80 2.07 2.18 2.46

2 .................................. Grass 68 36 36 2.56 2.68 3.06 3.65

3 ................................. Grass 120 72 72 2.21 2.10 2.47 2.82

4 .................................. Grass 68 36 36 2.10 2.21

4a ................................ Clover-Grass 0 72 72 2.57 4.00

5 .................................. Clover-Grass 0 72 72 2.47 2.65 2.92 3.24

6 .................................. Clover-Grass 0 144 144 1.59 2.17 a

7 .................................... Clover-Grass 0 144 144 2.22 2.12 2.38 3.02

8 ................................ Clover-Grass 0 72 72 2.57 3.58

Programs 1, 2, 3, 5 and 7 2.25 2.32 2.60 3.04 r

* Virgin soil before pastures were fertilized and planted.







58 Florida Agricultural Experiment Stations

increased from 2.32 percent in 1953 to 3.04 percent in 1957, for
an increase of 30 percent. There is a close relationship in sandy
soils between organic matter, water holding capacity and cation
exchange capacity. The increase in organic matter during this
trial and the resulting increase in water holding capacity and ex-
change capacity should have made an important contribution to
potential forage production as the experiment progressed. For-
age yields and quality were improved as the experiment pro-
gressed, but due to improvement in most factors responsible for
plant growth, it is difficult to assign definite contributions to the
many interrelated factors. Regression analyses of forage yields
on the percentages of organic matter were made for Programs
1, 2, 3, 5 and 7 separately and for Programs 1, 2 and 3 combined.
Comparisons were made only with yields obtained the same year
that samples were taken. No consistent relationships were found.
Minor Elements.-It was not known that minor elements were
needed for forage production, but they were applied as a precau-
tion against deficiency which would limit response from major
elements. Because of the uniform application of minor elements,
it was not possible to study them in this experiment.
However, supplemental studies on minor elements have been
made with soils from the Beef Research Unit. Harris (4) used
Leon fine sand with white clover and Coastal berumdagrass in pot
studies and obtained responses to copper, boron and molybdenum.
Winsor and Blue (16) also have obtained some yield response to
minor elements on Leon fine sand at the Beef Research Unit with
white clover and Pensacola bahiagrass in a long term, clipped
plot, field study. A combination treatment of copper and zinc
gave approximately 20 percent increase in yield of dry matter
and of forage nitrogen during the fifth year of the study and bor-
on gave an additional 10 percent increase. No fertilizer nitrogen
had been applied during the previous 2 years. Forage production
in this study was high even without minor elements, and 25 to 40
tons of forage per acre had been removed from the plots before
statistically significant differences were obtained. The responses
obtained indicate that copper and boron were the limiting ele-
ments. It would appear that boron should receive most attention
from a maintenance standpoint, since it leaches readily, particu-
larly when applied as borax. Copper is used as a mineral supple-
ment for cattle by most ranchers and it is not subject to severe
leaching.







Beef Production, Soil and Forage Analyses 59

ESTIMATED COSTS AND RETURNS
Establishment Cost per Acre.-Estimated costs per acre for
establishing pastures on each program are shown in Table 32.
For Programs 1 to 7, which were all improved, establishment costs
varied from $91 per acre for Program 1 to approximately $114 per
acre for Programs 5, 6 and 7. Establishment cost for Program 8
was only $31 per acre if both improved and unimproved acres are
considered. Costs for the improved part of Program 8 was $114
per acre, the same as Programs 5, 6, and 7. To arrive at total in-
vestment in improved pastures, value of land was added to es-
tablishment costs. When these pastures were established, value
of fenced cut-over land being used for pastures was estimated at
$30 per acre. When land value was added to establishment cost,
investment varied from $61 per acre for Program 8 to $144 per
acre for Programs 5, 6 and 7.
Annual Costs and Returns.-Estimated annual costs and value
of beef produced per acre and per cow for each program are shown
in Tables 33 and 34. Net costs per acre ranged from $12.61 for
Program 8 to $62.63 for Program 3. Net costs per pound for pro-
ducing beef were consistently higher on grass pastures than on
clover pastures. On grass programs, value of beef produced per
acre was equal to only about one-half of the total net cost per
acre. In Program 3, the annual cost of fertilizer and lime alone
was almost equal to the total value of beef produced.
Program 5 was the most economical for production of beef.
On this program, net cost for producing a pound of beef was 12.9
cents. The program showed a net return above all costs of ap-
proximately $8 per acre. Program 8, with a net cost of 15.2 cents
per pound of beef produced was the second most economical pro-
gram. Programs 5 and 8 were the only ones on which value of
the beef produced was more than net cost of producing the beef.
On a per-cow basis, value of beef produced was about $40.00
per acre on grass pastures. On clover pastures value of beef
varied from $50.82 on Program 4 to $59.19 on Program 5. Net
returns averaged about $11 per cow per year on Program 5 and
$2.00 per cow on Program 8.
Pounds of Beef Necessary to Cover Cost Items.-Returns from
following a specified practice depend on cost of the practice and
price of the product. Therefore, the relative profitableness chang-
es as price of the product changes. To indicate effects of changes
in price of beef on returns from improved pastures, calculations
were made of pounds of beef necessary at specified prices to cover






TABLE 32.-AVERAGE COST AND TOTAL INVESTMENT, PER ACRE OF ESTABLISHING PASTURES.

ITEM Program Number*
__1 2 F 3 4 5 6 7 | 8** _

Limestone and fertilizer:
Limestone ..---.................. 4.90 $ 4.70 $ 5.21 $ 7.35 $ 10.11 $ 9.80 $ 9.80 $ 2.78
Fertilizer ...................... 11.72 15.81 15.54 15.97 15.71 14.62 15.55 4.28
Top dressing ................ 3.56 6.94 9.03 7.14 7.01 7.22 7.44 1.93
Seeding Materials:
Bahia seed .-...........-- ..... 2.62 2.62 2.62 2.62 2.62 2.62 2.62 1.07
Pangola plant material 3.33 3.33 3.33 3.33 3.33 3.33 3.33 .68
Clover Seed _
Ladino ....... ............- .28 .85 .85 .85 .23
M. White .................. 1.10 3.30 3.30 3.30 .90
Hubam .............. --- -. .35 1.01 1.05 1.01 .29
K. Red .. ---..........-. -- .60 1.80 1.80 1.80 .49
N. Red ......................... -- -- .75 2.25 2.25 2.25 .62
Clover innoculent -......-.... ---- -- .04 .11 .11 .11 .03
TOTAL COST ... 5.95 5.95 5.95 9.07 15.27 15.31 15.27 4.31
Land clearing and
preparation:
Stump, pile, web plow
and disk ..........--..... 35.00 35.00 35.00 35.00 35.00 35.00 35.00 9.55
Level, disk, chop,
pick up and burn .... 20.00 20.00 20.00 20.00 20.00 20.00 20.00 5.45
Fertilizing and Seeding:
Disking .-----------------.. 2.50 2.50 2.50 2.50 2.50 2.50 2.50 .64
Dragging ................... 1.00 1.00 1.00 1.00 1.00 1.00 1.00 .27
Spreading fertilizer ... .88 1.51 1.49 1.52 1.50 1.40 1.49 .41
Seeding bahia seed .... .58 .58 .58 .58 .58 .58 .58 .24
Planting pangola I
material ........ .. 5.00 5.00 5.00 5.00 5.00 5.00 5.00 1.02
Seeding clover .......... .25 .75 .75 .75 .21
Total cost of I
Establishing ........ 91.09 98.99 101.30 105.38 114.43 113.18 114.38 31.09
Value of Land and Fence .. 30.00 30.00 30.00 30.00 30.00 30.00 30.00 30.00
TOTAL
INVESTMENT 121.09 128.99 131.30 135.38 144.43 143.18 144.38 61.09

Acres in Program ................ 16 12 8 10 8 6 8 22

* Average cost for both replications.
** Averages based on total acres in program.





TABLE 33.-AVERAGE COSTS AND RETURNS PER ACRE BY PROGRAMS.

Program Number
Item 1 2 3 4 5 1 6 7 8

Estimated Annual Costs:
Fertilizer and ground
limestone:
Mixed fertilizer .......... $ 4.79 $ 9.58 $ 19.17 $ 9.54 $ 9.47 $ 18.94 $ 18.93 $ 2.58
Top dressing ................ 2.02 3.93 5.89 2.75 --
Limestone .................... .98 1.22 1.63 1.36 1.63 1.63 1.63 .44
Total ................... 7.79 14.73 26.69 13.65 11.10 20.57 20.56 3.02
Maintenance Operations:
Spreading fertilizer .... .56 1.13 2.25 1.25 1.50 3.00 3.00 .41
Spreading top dressing .26 .50 .50 .35 -- -
Miscellaneous
maintenance ........... 2.00 2.00 2.00 2.00 2.00 2.00 2.00 .55
Harvesting silage ...... -- 3.56 2.40 3.38 3.25 3.19
Total direct costs 10.61 18.36 35.00 19.65 17.98 28.82 28.75 3.98
Interest on investment 5.88 6.10 6.11 6.41 6.87 6.80 6.85 2.96
Total pasture costs 16.49 24.46 41.11 26.06 24.85 35.62 35.60 6.94
Feed and Minerals:
41% cottonseed pellets .76 1.36 2.33 .92 -.51 -'
Silage ............................ -- -
Salt and bone meal .... .60 .70 .82 .57 .59 .51 .76 .17
Miscellaneous Livestock
cost .................................. 9.66 12.88 19.31 15.45 19.31 21.46 20.92 6.44
Total costs ........... 27.51 39.40 63.57 43.00 44.75 57.59 57.28 14.06
Less:
Credit for silage ........ .94 6.00 8.44 5.62 5.62 -
Credit for timber ........ -- --1.45
Net costs ............ 27.51 39.40 62.63 37.00 36.31 51.97 51.66 12.61
Production Value and
Cost of Beef:
Total production (lbs.) 99 135 202 198 282 287 280 83
Total value ................ $ 15.15 $ 20.66 $ 29.90 $ 30.49 $ 44.27 $ 44.49 $ 42.84 $ 13.11
Value per pound
(cents) .................... 15.3 15.3 14.8 15.4 15.7 15.5 15.3 15.8
Net cost per pound
(cents) .................... 27.9 29.2 31.0 18.7 12.9 18.1 18.5 15.2







TABLE 34.-AVERAGE COSTS AND RETURNS PER COW BY PROGRAMS.

S _Program Number
Item 1 | 2 3 4 5 6 7 8

Estimated Annual Costs:
Fertilizer and ground
limestone:
Mixed fertilizer ....-... $ 12.78 $ 19.16 $ 25.55 $ 15.91 $ 12.62 $ 22.72 $ 23.31 $ 10.33
Top dressing ............... 5.40 7.85 7.85 4.58 -----
Limestone .....------- 2.61 2.45 2.18 2.27 2.18 1.96 2.01 1.78
Total ...................... 20.79 29.46 35.58 22.76 14.80 24.68 25.32 12.11
Maintenance Operations:
Spreading fertilizer .. 1.50 2.25 3.00 2.08 2.00 3.60 3.69 1.64
Spreading top dressing .69 1.00 .67 .58 -- --- ---
Miscellaneous
maintenance ............ 5.33 4.00 2.67 3.33 2.67 2.40 2.46 2.18
Harvesting silage ..-...- -4.75 4.00 4.50 3.90 3.92
Total direct costs 28.31 36.71 46.67 32.75 23.97 34.58 35.39 15.93
Interest on Investment .... 15.67 12.21 8.15 10.69 9.16 8.16 8.43 11.83
Total pasture costs 43.98 48.92 54.82 43.44 33.13 42.74 43.82 27.76
Feed and Minerals:
41% cottonseed pellets 2.04 2.73 3.10 1.53 2.05
Silage ....................-.... -
Salt and bone meal .... 1.60 1.40 1.09 .95 .79 .62 .94 .70
Miscellaneous Livestock I
Costs ........--- ... 25.75 25.75 25.75 25.75 25.75 25.75 25.75 25.75
Total costs ........... 73.37 78.80 84.76 71.67 59.67 69.11 70.51 56.26
Less: "*
Credit for silage ....... -- 1.25 10.00 11.27 6.75 6.92 -
Credit for timber ........ 5.82
Net costs ............ 73.37 78.80 83.51 61.67 48.40 62.36 63.59 50.44
Production Value and
Cost of Beef:
Total production (lbs.) 263 270 270 330 377 345 344 331
Total value .................. $ 40.24 $ 41.31 $ 39.96 $ 50.82 $ 59.19 $ 53.48 $ 52.63 $ 52.30
Value per pound
(cents) ..........- ......- 15.3 15.3 14.8 15.4 15.7 15.5 15.3 15.8
Net cost per pound
(cents) ............-.. .. 27.9 29.2 31.0 18.7 12.9 18.1 18.5 15.2
_ _ _ _ _ _ -._ _ _ _ _ _ _ I _ _








Beef Production, Soil and Forage Analyses 63

total and individual items of costs (Table 35). At 10 cents per
pound the amount of beef necessary to cover costs of each pro-
gram would vary from 626 pounds per acre on Program 3 to 126
pounds on Program 8. With beef at 10 cents per pound, none of
the programs produced enough beef to cover cost of production.
At 25 cents per pound, the amount of beef per acre necessary
to cover net cost of each program would vary from 250 pounds
for Program 3 to 50 pounds for Program 8. At 25 cents per
pound, Program 3 was the only 1 on which production of beef was
not sufficient to cover cost of the program. At 20 cents per pound
for beef, production on Programs 1, 2 and 3 was not sufficient to
cover costs, while all of the clover programs would have made a
good profit.
Irrigation Cost for Program 6.-Programs 6 and 7 were sim-
ilar, except that Program 6 was set up with the expectation that
irrigation would be used as needed. A sprinkler type irrigation
system was to be used. Due to an inadequate supply of water and
shortage of equipment, the amount of irrigation applied was not
sufficient to have an appreciable effect on the production of for-
age. Therefore, cost for irrigation was not included in the sum-
mary of costs for Program 6.
Experiments with irrigation at the Dairy Unit at Hague would
indicate that an annual application of approximately 20 inches of
water above normal rainfall would be necessary to result in a
substantial increase in the production of forage. An estimate
was made of the costs to applying this amount of water to Pro-
gram 6 to determine the increase in beef production that would
be necessary to cover the cost of irrigation.
No data are available on the cost of irrigating pastures in
Florida. Agricultural engineers estimated it would cost $6,400
to install a sprinkler irrigation system to irrigate 40 acres, or an
investment of $160 per acre. It would require about 1.5 hours to
apply an acre-inch of water with such a system. Data from a
study of costs of irrigating tobacco indicated that fixed costs of
maintaining an irrigation system were 12 percent of the invest-
ment, and cost of operating the equipment, $1.50 per acre-inch.
Labor for applying water was estimated to be 75 cents per acre-
inch.
Based on these estimates, the cost of irrigating Program 6
would be $64.20 per acre: $19.20 per acre for fixed costs, $30.00
for operating the equipment and $15.00 for labor used in applying
'Unpublished data, Florida Agricultural Experiment Station.









TABLE 35.-BEEF PER ACRE NECESSARY AT SPECIFIED PRICES TO COVER SELECTED COSTS.

Item Program Number
1 2 | 3 4 5 6 7 8
Production of Beef per Acre ............................. .........-...... 99 1 135 202 198 282 287 280 83
Pounds of Beef Necessary to Cover Selected Costs with beef at 10 cents per Pound
Fertilizer and ground limestone .-....-....--- ....-- ..--. 78 147 267 136 111 206 206 30
Other direct pasture costs .....------------------------ 28 36 83 60 69 82 82 10
Interest on investment ............. ................................ 59 61 61 64 68 68 68 30
Supplemental feeds and minerals .-.......---.........----....... 14 21 31 15 6 5 8 7
Miscellaneous costs, less credits .-..........-------............. 96 129 184 95 109 159 153 49
Net costs ..... 7...................... ...................................... 275 394 626 370 363 520 517 126 .
Pounds of Beef Necessary to Cover Selected Costs with beef at 15 cents per Pound
Fertilizer and ground limestone --.........----................ 52 98 178 91 74 137 137 20
Other direct pasture costs ....................................... 19 24 55 40 46 55 54 6
Interest on investment ...................--..--................. 39 41 41 42 46 45 46 20
Supplemental feeds and minerals .....--...........................-- 9 13 21 10 4 3 5 5
Miscellaneous costs, less credits ..........................-........... 64 86 123 63 72 106 102 33 t
Net costs .......................................... ............. 183 262 418 246 242 346 344 84
Pounds of Beef Necessary to Cover Selected Costs with beef at 20 cents per Pound
Fertilizer and ground limestone ................................... 39 74 133 68 56 103 103 15
Other direct pasture costs .................................... 14 18 42 30 34 41 41 5
Interest on investment ........................------- ........ .......... 29 31 30 32 34 34 34 15
Supplemental feeds and minerals .................................. 7 10 16 8 3 3 4 3
Miscellaneous costs, less credits .-..................................... 48 64 92 47 55 79 76 25 t5
Net costs .........................- ........................................ 137 197 313 185 182 260 258 63
Pounds of Beef Necessary to Cover Selected Costs with Beef at 25 cents per Pound _
Fertilizer and ground limestone ................................ 31 59 107 55 44 82 82 12
Other direct pasture costs ........... ................................ 11 14 33 24 28 33 33 4
Other direct pasture costs ---------------------------- 11 14 33 24 28 33 33 4
Interest on investment ........-......-- .... -- ....----................ 24 24 24 25 28 27 27 12
Supplemental feeds and minerals ........................-........ 5 8 13 6 2 2 3 3
Miscellaneous costs, less credits ........................................ 39 52 73 38 43 64 62 19
Net costs ....................... ..................... ........... 110 157 250 148 145 208 207 50









Beef Production, Soil and Forage Analyses 65

water. Based on these calculations, to cover cost of irrigation,
production of beef on Program 6 would have to be increased 642
pounds per acre if beef was 10 cents per pound, 428 pounds if beef
was 15 cents, 321 pounds if beef was 20 cents, 257 pounds if beef
was 25 cents and 214 pounds if beef was 30 cents per pound.

DISCUSSION
With the prices prevailing during the course of this 5-year
study, only Programs 5 and 8 had incomes higher than the costs
of production. Program 5 was a clover-grass pasture fertilized
at the rate of 600 pounds of 0-12-12 per acre. Program 8 was a
combination of 1 acre of improved area similar to that of Program
5 with 2.5 acres of native area. No nitrogen was used on either
program. The only other data of this nature that has been re-
ported from Florida was a preliminary report by Kirk (7). In-
cluded in his report were the cost and productive figures from a
program very similar to number 8 in this study. The estimated
costs and production per cow were $55.65 and 320 pounds, re-
spectively. These values agree well with those of $50.44 ($56.26
before credit for timber production) and 331 pounds of calf per
cow obtained in Program 8.
The failure of the remaining programs to return a profit serve
to emphasize the necessity for productive cattle, careful planning,
skilled management and a good ranch site if cow-calf operations
are to be profitable on improved pastures in Florida. The estimat-
ed levels of production necessary to cover costs (Tables 35 and 36)
indicate that it is doubtful whether grass pastures without le-
gumes on flatwoods soils can support a cow-calf operation profit-
ably. Certainly, production costs must be lowered or beef prices
increased before pastures improved in this manner can be used
profitably in a cow-calf operation.
On the other hand, the results from Programs 5 and 8 indicate
that where clover can be grown successfully, cow-calf operations
may be extremely profitable on flatwoods soils. Program 5, for
example, produced beef for a net cost of 12.9 cents per pound.
This cost probably could be lowered somewhat as indicated below.

PROMISING METHODS FOR INCREASING PRODUCTION
WITHOUT INCREASING COSTS
The experiences gained during this trial suggest several pos-
sibilities for increasing production above the levels of the 5-year
averages obtained in this trial without increasing costs. During









66 Florida Agricultural Experiment Stations

the first years of this trial reproduction efficiency was lower than
what should be obtained in well managed herds. As shown in
Table 36, production levels during the last 2 years of the trial
were substantially higher than the 5-year average. It is felt that
this increase was brought about principally by culling irregular
producing cows. Well managed herds should be able to maintain
production levels equivalent to or in excess of that achieved dur-
ing the last 2 years of the trial. If this be true, it is estimated
that with production costs similar to those current during this
study, a well managed cow-calf operation on Program 5 should
produce beef for approximately 12 cents per pound.

TABLE 36.-PRODUCTION DATA DURING LAST TWO YEARS OF TRIAL
COMPARED WITH FIVE-YEAR AVERAGES AND PRODUCTION REQUIRED TO
MEET COSTS.

Average Pro- Production per cow required Net cost per
duction per to meet costs with beef pound of beef
Program cow valued per pound at produced
5-year I Last 2 I 5-yr. I Last 2
Av. yrs.* 10 I 15 20 250 Av. I yrs.*
lbs. Ibs. lbs. lbs. lbs. lbs. Cents Cents
1 -.... 263 389 734 488 366 294 27.9 18.9
2 ..-. 270 394 788 524 394 314 29.2 20.0
3 -..... 270 381 832 555 416 333 31.0 21.9
4 ....-. 330 405 618 411 309 247 18.7 15.2
5 ....... 377 412 483 322 242 193 12.9 11.7
6 ........ 345 389 624 415 312 250 18.1 16.0
7 ........ 344 392 636 423 317 255 18.5 16.2
8 ....... 331 399 504 336 252 200 15.2 12.6

The production levels shown in this column are somewhere near what should be obtained
in well managed commercial herds on improved pastures without creep feeding of calves.

A second possibility for increasing income would be to have
higher quality cattle, so that calves would sell for more per
pound. The foundation cows used in this study were of mediocre
quality. If calves had been of higher quality, they would have
sold for more money and the economic evaluation of the programs
would have improved accordingly. In operating on high cost in-
put programs, the importance of stocking the pastures with pro-
ductive high quality cattle can not be overemphasized.









Beef Production, Soil and Forage Analyses 67

The third possibility for increasing returns would be to cull all
open cows in the fall and replace them with pregnant heifers. The
returns from open cows off good pasture generally will be enough
to pay for their replacement. Thus, only pregnant cows would
be wintered and the weaning percent should be increased to 95
percent or above. This practice would increase income substan-
tially over the general practice of maintaining a number of open
cows and is a procedure that should be emphasized in enterprises
where pasture costs are high.

QUESTIONABLE MEANS FOR INCREASING PRODUCTION
One possibility that naturally arises is whether production
could be increased by raising the stocking rate. The forage pro-
duced and the estimated percent of the forage that was utilized
by the cattle, based on the National Research Council require-
ments for dry matter, are shown in Table 37. The estimated utili-
zation varied from 64 to 80 percent in the all improved pastures
and was 60 percent in Program 8, where much of the forage in the
native area was of poor quality and not palatable to the cattle.
On the basis of these estimates, utilization was high enough that
it appears unlikely that beef production could be increased sig-
nificantly by increasing the stocking rate. More likely, production
would be lowered, due to lighter weights of individual animals and
lowered reproductive efficiency. -It appears that the stocking
rates in effect during this trial were near optimum from the
standpoint of total production per acre.
The high utilization of roughage observed with year-long graz-
ing in this study suggests further that harvesting of roughage
for winter feeding would not increase utilization enough to pay for
the machinery and labor costs involved in harvesting and feeding
the roughage. Forage definitely should be harvested and stored
for emergency feeding, but the results from this trial confirm the
generally held contention of ranchers that grazing should be prac-
ticed insofar as possible and feeding of harvested feed held to a
minimum.
Another suggestion that has been advanced for increasing
production is to wean calves at an age older than 7 months, the
age at which calves were weaned in this trial. There are no data
from this trial or in the literature that bear directly on this mat-
ter. It is a problem that merits investigation. The experience
and observations of animal husbandmen, however, lead to the be-
lief that in most operations weaning of calves much later than an










oo


TABLE 37.-BEEF AND FORAGE PRODUCTION, FORAGE UTILIZATION AND INDEX OF SELECTED ITEMS BY PROGRAMS.

Produc- Avail- Pasture Forage Forage Index (Program 5 = 100)
Stion of able cost per Avail- Utiliza- Beef Forage PastureI Forage Net Net
Program I beef per forage* 100 lbs. able tion by Produc- Produc- cost per Avail- Cost Cost
acre per acre forage per cow cattle** tion tion 100 lbs. able per lb. per
per acre per acre forage per cow of beef Acre
Pounds Pounds Cents Pounds Percent .
1 ........ 99 4,663 35.4 12,450 69.6 35 53 $125 110 216 75.8

2 ...... 135 6,462 37.8 12,924 67.1 48 74 133 114 226 108.5
3 ........ 202 8,577 47.8 11,407 76.0 72 98 168 101 240 172.5
4 ........ 198 8,088 31.6 13,507 64.2 70 94 111 119 145 101.9
5 ........ 282 8,531 28.4 11,346 76.4 100 100 100 100 100 100.0

6 ........ 287 9,064 38.6 10,829 80.1 102 105 136 96 140 143.0
7 ....... 280 8,933 39.2 11,881 73.0 99 104 138 105 143 142.3

8 --... 83 3,623t 19.2t 14,492t 59.8t 29 41 68 128t 118 34.7

Estimated forage yield less forage cut and not fed back in program.
** Estimated on basis of National Research Council requirements of 8670 pounds dry matter per cow per year.
SIncludes roughage from native pasture.







Beef Production, Soil and Forage Analyses 69

average of 7 months might decrease rather than increase income
over a period of years, due to decreased weights of cows going
into the winter and resultant lowered production and reduced sal-
vage value of cull animals. It is possible, however, that under
good conditions weaning at a later age could be practiced to ad-
vantage.
Creep feeding of calves to increase weight and grade has been
advocated by some. This practice would increase costs. Since no
data on creep feeding on the types of pasture programs used in
this study are available, there is no basis for an objective evalua-
tion. In general, however, creep feeding has not proven profitable
where growth rate of calves has been as good as that obtained in
this study.

POSSIBILITY FOR REDUCING FERTILIZER COST
As indicated in the section on soils studies (Table 26), phos-
phate levels increased in the soil during the course of this trial.
In view of these results and indications from other studies by
Blue and Gammon (1) that 40 pounds of phosphate annually were
adequate for maximum clover yields, it appears that phosphate
applications lower than the amounts used in this study might
have been used without lowering production in the clover pro-
grams. One program with phosphate applied at the rate of 30
pounds per acre will be investigated in the next phase of this pro-
ject.
Potash at the rate of 72 pounds per acre (Programs 5 and 8)
apparently was adequate to support maximum growth of clover.
How much applications of potash could have been lowered without
reducing yields is not known. In view of general experience,
however, applications of much less than 70 pounds per acre would
likely result in lowered forage production. Potash application at
the rate of 60 pounds per acre will be included in the next phase
of this study.

RESPONSE FROM INCREASING FERTILIZER LEVELS
The cost per pound for producing beef increased progressively
with increasing rate of fertilizer application in the grass programs
(Tables 33, 34, 35 and 37). This was due to the fact that as fer-
tilization rate was increased, costs increased out of proportion to
the increase in production of either forage or beef (Table 37).
This means that for the conditions in this experiment the higher
rates of fertilization proved to be inefficient in terms of beef pro-







70 Florida Agricultural Experiment Stations

duction. There is further need to study management problems
including fertilizer rates, ratios and time of application in de-
veloping cow-calf operations capable of yielding a high net return
for the operator.
Historically, cow-calf operations have been largely confined
to extensive type operations with relatively low input into pas-
tures, and the quality of feed required is usually below that of
steer feeding programs. As the value of land increases, the need
for more intensive type of operation becomes obvious. In gen-
eral, the highest yields of forage per acre are associated with the
highest quality forage because of the high rates of fertilization
(especially nitrogen) necessary to produce these yields. If and
when the need for more intensive production per acre develops,
it may be necessary to consider a combined cow-calf and steer
feeding program in order to best utilize the quality and quantity
of forage produced.
It is obvious from the results of this trial that clover should
be included in pastures where moisture conditions are satisfactory
for clover growth. Clover programs receiving 600 pounds of 0-12-
12 annually produced at essentially the same rate as programs
which received 1,200 pounds, indicating the minimum fertilizer
requirements have been exceeded on clover pastures under con-
tinuous grazing. It appears possible that the efficiency with
which applied nutrients are retained where cattle excrement con-
stantly returns nutrients to the soil has been underestimated.

SUMMARY
Five years' results from the first phase of a coordinated study
of pasture programs for beef production in north central Florida
are presented. Eight programs at the Beef Research Unit,
Gainesville, were evaluated from the standpoint of beef produc-
tion with a cow-calf operation, soils analyses, forage production,
forage composition and an economic analysis of each program.
Three all-grass programs (1, 2 and 3) received increasing
amounts of N, P205 and K20 in pounds per acre as follows: Pro-
gram 1). 34, 18 and 18; Program 2). 68, 36 and 36; and Program
3). 120, 72 and 72 respectively. One grass-clover program (No.
5) received 72 pounds each of P205 and K20 annually and 2 grass-
clover programs (Nos. 6 and 7) received double these amounts.
Program 6 was to be irrigated, but water supply was inadequate;
and 6 may be considered a replicate of 7. Program 4 consisted of
two-thirds all-grass pasture fertilized the same as Program 2 and








Beef Production, Soil and Forage Analyses 71

one-third grass-clover fertilized at the same rate as Program 5.
Program 8 consisted of 1 acre of clover pasture fertilized the
same as Program 5, in combination with 2.5 acres of cut-over
native pasture which received no fertilization.

ANIMAL RESPONSE AND BEEF PRODUCTION
The average weaning percentages for the 3 all-grass programs
were 63, 64 and 66 percent, while those from the 3 grass-clover
programs were 85, 83 and 82 percent. Program 4, a combination
of one-third clover and two-thirds grass, had an average weaning
percent of 76; and the combination of native and improved pas-
ture (Program 8), 77 percent. In the all-grass programs (1, 2 and
3) reproduction in nursing cows was nil during the first 2 years
of the trial but increased to that of the cows on clover pastures
during the last 2 years. These results are in agreement with
low reproduction generally in Florida among young nursing cows
on all-grass flatwoods pastures. The improvement in reproduc-
tion as the trial progressed was attributed to increasing maturity
of the cows, culling for the reproductive failure and possibly to
the invasion of clover into the grass programs. It was concluded
that the beneficial effects of clover pastures on reproduction were
related to better quality and seasonal distribution of forage and
possibly to some specific qualitative effect of clover beneficial to
the occurrence of heat in young cows nursing calves.
The average weaning weights of calves were 417, 423 and 408
pounds, respectively, for the 3 all-grass programs (1, 2 and 3);
443, 417 and 421 pounds for the clover-grass programs (5, 6 and
7); and 435 and 428 pounds, respectively, for the 2 combination
programs 4 and 8.
/Thus, the principal effect of pasture programs on production
of beef was that the clover programs had a highly significant ad-
vantage in reproduction efficiency, had a slight advantage in
weaning weight of calves and required less supplemental feed
than grass pastures The production of beef, measured as pounds
of weanling calf per cow and per acre, was similar in all 3 clover
programs, averaging 356 and 283 pounds, respectively. Produc-
tion per cow was almost identical for the 3 all-grass programs, av-
eraging 268 pounds, while production per acre increased as fertil-
izer applications increased and was 99, 135 and 202 pounds, respec-
tively, for Programs 1, 2 and 3. The production per cow was 330
pounds and production per acre 282 pounds for Program 4 (1/3
clover-grass and 2 grass). In Program 8 (1 acre of improved to


A







72 Florida Agricultural Experiment Stations

2.5 acres of native pasture) production per cow was 331 pounds,
and the production per acre, 83 pounds.

SOIL STUDIES
Organic matter averaged 2.25 percent in virgin soil, with vari-
ations from less than 1 percent to approximately 7 percent. The
ratio of percentage soil organic matter to milliequivalents ex-
change capacity was 1:2. The ratio of percentage organic matter
to moisture equivalent percentage was 1:1.36. Soil pH averaged
4.9, varying from 4.5 to 5.2, depending on the percentage organic
matter. Ammonium acetate extractable calcium averaged 200
pounds per acre; extractable P205, 14 pounds per acre; total phos-
phate, 140 pounds; and K20, 54 pounds per acre in virgin soil.
There was a high correlation between total soil nitrogen and
soil organic matter. Nitrate production was enhanced by lime,
and the importance of liming just prior to grass establishment for
grass-clover pastures was emphasized.
Total phosphate and ammonium acetate (pH 4.8) extractable
phosphate increased significantly with years. Total phosphate
was significantly correlated with soil organic matter. On a with-
in program basis there was no significant correlation between ex-
tractable soil phosphate and forage yields. Forage yields per acre
increased progressively in Programs 1, 2 and 3 as phosphate levels
increased, but this relationship was coincidental with increasing
rates of nitrogen applications.
Extractable soil potash increased significantly with years and
with increasing levels of fertilizer. Accumulation was small,
however, when compared to phosphate. Potash retention during
the 4-month winter season was high for all years. This probably
explains the lack of response from spring applied potash. Within
programs, there was no correlation between extractable soil pot-
ash and forage yields.
Soil pH for Programs 1, 2 and 3 reached an average maximum
of 5.3 from 1 ton of lime and declined after 2 years to 4.9. In-
creasing rates of nitrogen reduced soil pH slightly. There was
a high correlation between soil organic matter and pH. Soil pH
in irrigated pastures was increased by calcium in the irrigation
water. Neither grass nor clover-grass forage yields were signifi-
cantly related to soil pH or extractable calcium. The pH range
for clover-grass pastures was 5.1 to 6.0. Although it was recog-
nized that the application of lime and (or) phosphate to the sur-
face of an undisturbed sod tends to develop localized areas widely



L








Beef Production, Soil and Forage Analyses 73

different in pH level as well as calcium and phosphate content,
this condition was not specifically studied during the first 5
years of this experiment. Analyses reported were on the basis of
the standard 0-6" soil sampling agreed upon prior to the initia-
tion of the experiment and regardless of the method of tillage or
lack of same. Knowledge of these facts should be taken into
consideration when reviewing the data reported.
Soil organic matter increased from 2.25 percent to approxi-
mately 3.0 percent from 1953 to 1957. Neither the program nor
the initial organic matter content apparently influenced accumula-
tion.
FORAGE YIELDS AND ANALYSES
The annual forage yields for Programs 1 through 8 were, re-
spectively, 4,663, 6,462, 8,602, 8,248, 8,756, 9,214, 9,063 and 7,566
pounds of oven-dry forage per acre. The native grass-woods
area in Program 8 produced 2,168 pounds of oven-dry forage per
acre. Distribution of forage for grazing was better in the grass-
clover programs, where growth preceded that in the grass pas-
tures from 4 to 6 weeks. Forage for winter grazing was obtained
by deferred grazing of 1/3 or more of the area except in Program 3,
where forage was harvested for winter feeding.
Composition of the forage varied widely with season and prox-
imity to time of fertilization in the grass programs. The average
protein content of forage on an oven-dry basis during the growing
season was approximately 8 percent for the grass programs and 12
percent for the clover-grass programs. Protein content of frosted
pasture grass deteriorated to approximately 3 percent by mid-
winter, but cattle apparently were able to meet their protein needs
from clover in the grass-clover programs. Cows on the grass pro-
grams received protein supplement during the winter months.
The calcium content of forage from clover programs averaged 0.43
percent, while that of grass programs was 0.23 percent.
Pangolagrass in clover programs and heavily fertilized grass
programs suffered severe winter-kill and was replaced gradually
by other plants. Coastal bermudagrass did not establish well or
maintain a satisfactory stand in low, wet areas. Bahiagrass
maintained a good stand in all but extremely low, wet areas.
Ladino, red and Hubam clovers almost disappeared from the
original mixed stands, leaving mostly only white clover after 3
years. White clover has increased steadily in density of stand,
has spread uniformly over all but a few areas, and has shown a
steady increase in the percent of biennial plants which survive the


A








74 Florida Agricultural Experiment Stations

summer. This live-over clover has supplied significant amounts
of grazing from October until seeding clover was ready to graze,
usually in February.

ECONOMIC ANALYSES
In estimating costs and returns, charges for materials used
and various operations performed were made on the basis of the
levels used in each program. Prices used and costs for perform-
ing various operations were charged at rates estimated for a
commercial operation. Interest on investment was charged at 5
percent. Income was calculated from the weight and market
value of the calves produced in the program.
Land with all the timber removed was valued at $30 per acre.
Costs for clearing land and preparation for planting amounted to
$55 per acre. These costs along with charges for seed, fertilizer
and planting resulted in total establishment costs of $121, $129
and $131 per acre for the respective all-grass programs (1, 2 and
3) ; $144 for each of the clover-grass programs (5, 6 and 7); $135
for program 4; and $61 per acre for Program 8, which consisted
of a combination of improved and native pasture.
The total annual cost per cow, including interest on invest-
ment, amounted to $73, $74 and $84 for all-grass programs; $48,
$62 and $64 for clover-grass programs; $62 for Program 4 (%
grass, 1/3 clover-grass) and $50 for Program 8, which consisted of
1 acre of clover-grass in combination with 2.5 acres of native pas-
ture. Annual income per cow amounted to $40, $41 and $40 for
all grass programs; $59, $53 and $53 for clover programs; $50 for
Program 4 and $52 for Program 8. Thus, most of the programs in
this study produced beef at an economic loss. However, Program
5, which was a clover-grass pasture fertilized at the rate of 600
pounds of 0-12-12 annually, and Program, 8 which consisted of
clover-grass pasture in combination with native pasture, produced
beef at a profit during a period when the calves produced averaged
15.8 cents per pound.

MAJOR RESULTS AND CONCLUSIONS
1. Where moisture conditions are favorable for clover growth,
cow-calf operations on flatwoods pastures can be made to produce
beef at a substantial profit with prices prevailing from 1952 to
1958.
2. Clover-grass pastures fertilized at the rate of 600 pounds
of 0-12-12 annually produced substantially the same amount of










Beef Production, Soil and Forage Analyses 75

forage and had a carrying capacity for cattle similar to pastures
receiving twice this amount. Fertilizer levels lower than 600
pounds were not used on clover-grass pastures in this study.
3. Clover-grass pastures produced beef at approximately 60
percent of the cost for all-grass pastures. The advantages for
the clover-grass pastures included a higher weaning percent (83
vs. 64 percent), slightly heavier calves (427 vs. 416 pounds) and
a lower cost per head for supporting cows ($56 vs. $79).
4. The results of this trial indicate that all-grass pastures on
areas comparable to the Beef Research Unit are not profitable for
cow-calf operations. Costs per pound of beef produced on grass
programs increased as rate of fertilization was increased. The
need for more research on low to moderate cost pasture programs
is indicated.
ACKNOWLEDGMENTS
Personnel in addition to the authors who were closely associated with
the project included Dr. T. J. Cunha, Head, Department of Animal Hus-
bandry and Nutrition; Dr. F. H. Hull, Head, Department of Agronomy; Dr.
F. B. Smith, Head, Soils Department; Frazier Rogers, Head, Department
of Agricultural Engineering (now deceased); Dr. J. R. Beckenbach, Direc-
tor; Dr. R. W. Bledsoe, Associate Director (now deceased); Dr. H. H.
Wilkowske, Assistant Director; G. R. Freeman, Superintendent, Field Opera-
tions; J. H. Norton, Assistant Agricultural Engineer; C. S. Hoveland, Assis-
tant Agronomist; and R. J. Bullock, Assistant Soil Biochemist.
These personnel and the authors composed the coordinating committee
for the Beef Research Unit. The committee met monthly and was presided
over by the Chairman of the Department of Animal Husbandry and Nutri-
tion. The Project Leader from Animal Husbandry and Nutrition served
as the executive representative of the committee and supervised operation
of the project.
Appreciation is expressed to Mrs. Joann Moss and Mrs. Betty Graham,
Laboratory Assistants in Soils, for their help with laboratory and statistical
analyses. Credit is due to R. L. Gilman, Mrs. B. N. Winnie and other tech-
nicians in the Agronomy laboratory for chemical analyses of many forage
samples.
Special acknowledgement is made to A. G. Lewis and J. D. Wright,
Herdsmen. To them goes much of the credit for clover pastures, especially,
which have flourished beyond expectation.
LITERATURE CITED
1. Blue, W. G., and N. Gammon, Jr. Rates and Ratios of Nitrogen, Phos-
phorus and Potassium for White Clover and Pangolagrass on Rex Fine
Sand. Proc. Soil Sci. Soc. Fla. 15; 208-218, 1955.
2. Burton, Glenn W. Coastal Bermuda-A triple-treat Grass on the Cattle-
man's Team. Better Crops 37: 6-10 and 45, 1953.
3. Fiske, C. H. and Y. J. Subbarow. The Colorimetric Determination of
Phosphorus. J. Biol. Chem. 66: 375, 1925.










76 Florida Agricultural Experiment Stations

4. Harris, H. C. Project 440. Fla. Agri. Expt. Sta. Annual Report, p. 43,
1957.
5. Hazel, L. H. The Covariance of Multiple Classification Tables with
Unequal Subclass Numbers. Biometrics Bul. 2: 21-25, 1946.
6. Henderson, J. R. The Soils of Florida. Fla. Agr. Expt. Sta. Bul. 334,
1939.
7. Kirk, W. G. Returns from beef herd. Unpublished mimeo report
Range Cattle Field Day, 1956.
8. Neller, J. R., D. W. Jones, Nathan Gammon, Jr. and R. B. Forbes.
Leaching of Fertilizer Phosphorus in Acid Sandy Soils as Affected by
Lime. Fla. Agr. Expt. St. Cir. S-32, 1951.
9. Neller, J. R., H. W. Lundy, and D. W. Jones. Relation between Soluble
Phosphorus in Fertilized Soils and Growth Response of Pasture Forage.
Fla. Agr. Expt. Sta. Bul. 558, 1955.
10. Peech, Michael (Revised by T. W. Young). Chemical Studies on Soils
from Florida Citrus Groves. Fla. Agr. Expt. Sta. Bul. 448. p. 15, 1948.
11. Piper, C. S. Soil and Plant Analysis pp. 89-91. Interscience Publishers,
Inc., New York. 1950.
12. Reuss, L. A. Costs of Clearing Land and Establishing Improved Pas-
tures in Central Florida. Fla. Agr. Expt. Sta. Bul. 600, 1958.
13. Volk, G. M. and C. E. Bell. Soil Reaction (pH). Fla. Agr. Expt. Sta.
Bul. 400, p. 14. 1944.
14. Walkley, A. An Examination of Methods for Determining Organic
Carbon and Nitrogen in Soils. Jour. Agr. Sci. 25: 598-609, 1935.
15. Warnick, A. C. and M. Koger. Unpublished data.
16. Winsor, H. W. and W. G. Blue. Project 785. Fla. Agr. Expt. Sta.
Annual Report, p. 161. 1958.
17. Witt, H. G., A. C. Warnick, M. Koger and T. J. Cunha. The Effect of
Level of Protein Intake and Alfalfa Meal on Reproduction and Gains
in Beef Cows. Jour. Animal Sci. 17:1211. 1958.





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