Progress Report Series No. 99
Agricultural Experiment Station
AUBURN UNIVERSITY
February 1972
2. V. Smith, Director
Auburn, Alabama
Soil Fertility Experiments with Peanuts in 1971
Dallas H-artzog and Fred Adams'
THEI COOPERATIVE RESEARCH PROGRAM begun in
1967 to better define soil fertility requirements of
peanuts and to improve correlation between ferti-
lizer requirements and soil-test values by conducting
experiments on farmers' fields was continued in 1971.
Thirty-one experiments were initiated in 1971 in
seven counties and 23 were harvested (8 in Henry,
5 in Barbour, 3 in Dale, 2 each in Coffee, Crenshaw,
and Pike, and 1 in Houston).
The experimental area on each farm was divided
into either 8, 12, 16, or 20 plots, each plot being 4
rows wide and 100 feet long. Each farmer planted,
cultivated, dusted or sprayed, and harvested peanuts
within all plots the same as those in the remainder
of his field. Where the farmer did not carry out an
effective program for the control of leafspot, the
test area was sprayed with Benlate three times by
the researchers.
All experimental materials were applied by the
researchers. Four plots in each experiment received
no treatment; the remaining plots consisted of four
replications of one or more of the following treat-
ments: (1) a phosphorus-potassium fertilizer, (2)
gypsum, basic slag, or Fairfield slag, (3) boron, (4)
lime.
4 Research Associate and Professor, Department of Agronomy
and Soils.
FERTILIZER (P AND K) EXPERIMENTS
Five experiments were conducted to determine if
fertilizer should be applied to peanuts in the spring
on sois testing ow or "medium in phosphorus
(P) or potassium (K). In three of these experi-
ments, the fertilizer was broadcast and then turned
(Bostick, Deloney, and Morgan farms). In another
experiment, the fertilizer was broadcast after the
land had been turned and disked (Johnson farm).
The fertilizer was drilled at planting time in the
fifth experiment (Fuquay farm). The crop preced-
ing peanuts is listed in Table 1 for each farm.
Fertilizer was broadcast in four of the experiments
at a rate of 400 pounds per acre of 0-10-20 to one-
half of the experimental plots; the other plots re-
ceived no fertilizer. With the "drilled fertilizer" ex-
periment, the fertilized plots received 250 pounds
per acre of a 5-15-30 plus boron.
Two experiments were with the 'Florigiant' va-
riety, two with 'Florunner,' and one with 'Early Run-
ner.' Three of the soils 
tested "high" or "very high"
in phosphorus, one "medium," and one "low"; four
tested "low" in potassium 
and one "medium."
The results of these experiments are given in
Table 1 and confirm results of experiments from
previous years. Fertilizer did not increase yield or
TABLE 1. EFFECT OF BROADCAST FERTILIZER ON YIELD AND SMK OF 'FLORIGIANT, 'FLORUNNER', AND 'EARLY RUNNER' PEANUTS,
ALABAMA, 1971
Variety and farmer County Soil type 1970 Soil-test values Yield per acre
1  
SMK
crop pH P K 
No fert. Fert. No fert. Fert.
Lb./A Lb./A Lb. Lb. Pct. Pct.
Florigiant
J. Bostick Henry Dothan loamy sand idle 5.5 47(M) 56(L) 2,630 2,320 66 67
B. Deloney, Jr......... Dale Lucy loamy sand corn 6.4 145(VH) 39(L) 4,590 4,600 73 74
Florunner
D. Morgan------------ Henry Fuquay loamy sand corn 6.2 94(H) 79(M) 4,330 4,540 74 73
L. E. & J. H. Johnson---- Henry Fuquay loamy sand Bahia- 5.7 14(L) 37(L) 2,700 2,560 73 69
grass
Early Runner
T. D. Fuquay- Barbour Dothan loamy sand corn 6.2 180(VH) 55(L) 3,150 3,430 77 75
Fertilizer did not statistically increase or decrease yield.
2 Fertilizer drilled.
TABLE 2. EFFECT OF RYE AND SPRING-APPLIED FERTILIZER ON YIELD AND SMK or 'FLORIGIANT' AND FLORUNNER PEANUTS, ALABAMA, 1971
Yield per acre
2  
SMK
Variety and farmer County Soil type Soil test values Rye Fallow Rye Fallow
pH P 
K No 
Fert. No 
Fert. No 
Fert. No Fert.
fert. Fert. fert. Fert. fert. t. fert. Fert.
Lb./A Lb./A Lb. Lb. Lb. Lb. Pct. Pct. Pct. Pct.
Florunner
Marshall Bro._
Faceville
Henry sandy loam 5.6 66(H) 77(M) 4,550 4,520 4,790 4,830
Florigiant
Alaga
F. Martin-------- Barbour fine sand 5.1 48(M) 75(M) 8,060 3,010 2,770 2,930
SAll plots received a fall application of fertilizer.
2 Yields were not increased or decreased statistically by turned-under rye or spring-applied fertilizer.
grade of peanuts in any experiment. These experi-
ments continue to show that a direct application of
fertilizer to peanuts is not an economical practice.
Rye as a Cover Crop. Planting rye as a winter
cover crop preceding peanuts has become a fairly
common practice in the Wiregrass area. It has the
obvious asset of providing winter grazing for cattle.
In addition, it may have a beneficial effect upon the
following peanut crop. To test this possibility, two
experiments were conducted in which the effect of
rye as a cover crop on peanuts was measured, Table
2. Rye was planted and fertilized in November 1970
and allowed to grow on one-half the plots. After
turning under the rye in the spring, one-half of the
plots were fertilized with 0-10-20 at the rate of 400
pounds per acre. The results in Table 2 show 
no
benefit from the rye or from the fertilizer applied
directly to peanuts in the spring. Excellent yields
were made in both experiments: 21/4 tons per 
acre
for one and 11/2 tons for the other.
77 76 78 77
71 71 69 70
CALCIUM (Ca) EXPERIMENTS
Eleven experiments were harvested in which the
effect of calcium, applied as 1,000 pounds per acre
of gypsum at early blooming time, was determined.
In addition, two of the experiments compared gyp-
sum with basic slag and five compared gypsum
with Fairfield slag (Fairfield slag is a by-product
of modern steel-making processes and is similar to
basic slag). Soil-test calcium ranged from 64 pounds
per acre (low) to 512 pounds per acre (high) ahd
soil pH ranged from 4.8 to 6.3. Thus, a wide range
in soil calcium and soil acidity was represented by
these tests. Results are summarized in Table 3.
Yields were increased by gypsum only on soils
testing 214 pounds per acre (low) of calcium or
less. Yields were not affected by gypsum on soils
testing higher than this in available calcium.
Yields on the three soils "low" in calcium planted
to 'Florigiants' were increased about 600 to 800
pounds per acre by the gypsum application. Gypsum
TABLE 3. EFFECT OF TOPDRESSING CALCIUM AT RATE OF 1,000 POUNDS PER ACRE OF GYPSUM, BASIC SLAG, OR FAIRFIELD SLAG
ON YIELD AND PER CENT SOUND MATURE KERNEL (SMK) OF PEANUTS, ALABAMA, 1971
Variety and farmer County
Soil type
Yield per acre SMK
soil soil- Fair- Gyp- Basic Fair-
pH No Ca ypsum Basic field No Ca Gyp- Bas field
N Gslag 
slag sum 
slag slag
Lb./A Lb. Lb. Lb. Lb. Pct. Pct. Pct. Pct.
Florigiant
H. Hartzog and Sons-
F. Martin
1
D. Averett
D. and L. McCart ..
Florunner
Barbour
Henry
Coffee
Coffee
Dothan loamy sand
Troup loamy sand
Red Bay fine sandy loam
Norfolk sandy loam
4.8
5.7
5.6
5.6
87(L)
167(L)
214(L)
392(M)
2,0602
2,9102
2,6902
2,370
J. Hartzog Barbour Tifton loamy 
sand 4.9 64(L) 1,230
-
E. Strickland. Crenshaw Brogdon loamy sand 6.0 294(M) 4,850
E. Strickland........ Crenshaw Wagram loamy sand 5.8 319(M) 
4,230
0. and B. Deal------ Dale Darco sand 6.0 337(M) 
3,320
J. L. Falkner-1.. Henry Dothan sandy loam 6.1 402(H) 3,980
J. R. (Jack) Kelly Houston Dothan sandy loam 6.3 453(H) 3,780
J. L. Falkner-2------ Henry Tifton sandy loam 6.3 512(H) 
3,840
1 This experiment also included a "lime" treatment (see Table 4).
2 Yield is statistically greater than yield on plots receiving no gypsum.
SPercentage SMK is statistically greater than SMK on plots receiving no gypsum.
2,810 2
3,5002
3,300'
2,240
1,770
4,810
4,520
3,200
3,950
3,670
4,050
513
643
2,770 67
72
1,590
4,330
43
65
702
712
70
74
68
76
77
73
76
75
76
65
75
76
70
77
73
76
75
3,530
4,020
3,740
3,890
74
76
73
76
.~
TABLE 4. EFFECT OF LIME ON YIELD AND SMK OF FLORIGIANT AND 'FLORUNNER PEANUTS, ALABAMA, 1971
Yield per acre SMK
Variety and farmer 
County Soil type 
Soil pH Soil-test Ca Nie 
ie Nlm
No lime Lime No lime Lime
Lb./A Lb. Lb. Pct. Pct.
Florunner
A. C. Fomen and Deal Bro.......... Dale Lakeland loamy sand
Florigiant
E. W. Washington Henry Wicksburg loamy san
R. Griffin and Sons... Barbour Fuquay loamy sand
F. Martin Henry Troup loamy sand
1 All plots received gypsum applied by farmer.
2 Yield is statistically greater than yield 
on unlimed plots.
SPercentage SMK is statistically greater than SMK on unlimed plots.
also increased percentage SMK in two of these tests,
one by 19 per cent. Only one "low" calcium soil
was planted to 'Florunner,' and gypsum also in-
creased its yield by more than 500 pounds per acre.
Because this field was very acid, there is little doubt
that the yield of the 'Florunners' was reduced by the
very low soil pH (4.9) even on the plots receiving
gypsum.
The effect of applying basic slag or Fairfield slag
at early bloom was tested at seven sites. However,
only two of these soils proved to be deficient in cal-
cium and, therefore, suitable for a gypsum-slag com-
parison (H. Hartzog and Averett farms). In neither
of these experiments was slag found to have any
value as a calcium source when applied in this 
man-
ner, whereas gypsum increased yields by 600 to 800
pounds per acre on the two soils that were "low" in
calcium.
LIME EXPERIMENTS
Four experiments in which 1 ton per acre of dolo-
mitic limestone was applied to peanuts were har-
vested in 1971, Table 4. Lime was applied in No-
vember 1970 on the Fomen-Deal farm; subsequently,
the land was disked and turned. Lime was applied
and disked-in in the spring on the other three farms
after the land had been turned and disked.
Soil pH ranged from 4.9 to 5.7 and soil calcium
was "low" in each case. The most acid soil was on
the Fomen-Deal farm where the farmer added 450
pounds per acre of gypsum to all plots. Without
lime (but with gypsum), the yield was 1,410 pounds
per acre with a SMK of 77 per cent. With lime, how-
ever, the yield was 3,740 pounds, an increase of
4.9 75(L) 1,41012 3,7401' 77
id 5.3
5.4
5.7
186(L)
76(L)
167(L)
571
3,5101 3,5601 -69
2,9102 3,4802 
64'
74
6 2 
'
70
70'
2,330 pounds per acre. These yields provide a strik-
ing example of how lime serves as more than just a
source of calcium on very acid soils. They also show
that farmers suffer serious economic losses by not
liming such soils.
Yields on the Washington farm (pH 5.3) were not
obtained because of a harvesting problem, but sam-
ples from the plots were taken and graded. The re-
sults showed an increase of 5 per cent in percentage
SMK from the lime, and it is reasonable to infer
from this that there was also a yield increase from
the application of lime.
Lime did not affect yield on the Griffin farm with
soil pH at 5.4 and soil-test calcium at 76. However,
the farmer applied 650 pounds per acre of gypsum
to all plots, thus supplying adequate calcium to both
unlimed and limed plots.
The experiment on the Martin farm (pH 5.7)
showed that lime was not needed to increase soil
pH but did serve as a satisfactory source of calcium.
Both yield and percentage SMK were increased
about the same from applications of gypsum and
lime on this farm, Table 3. This shows that the in-
crease in yield resulted from the application of cal-
cium and not from the change in pH caused by lime.
BORON (B) EXPERIMENTS
Two experiments were harvested in which boron
was added at a rate of 1 pound per acre, Table 5.
Neither showed any evidence of the telltale symptom
of boron deficiency - hollow-heart - even with soil-
test boron at about 0.1 pound per acre. Thus, the
"critical" soil boron 
level below which 
deficiency oc-
curs continues to vary from year to year because
TABLE 5. EFFECT OF BORON FERTILIZER ON YIELD AND PER CENT SOUND MATURE KERNEL (SMK), ALABAMA, 1971
Soil-test Yield per acre
1  
SMK
Variety and farmer 
County Soil type 
B No B Added 
B No B Added B
Lb./A Lb. Lb. Pct. Pct.
Florunner
H. E. McDaniel- Pike Dothan loamy sand
Virginia-67
L. Windham -------------- --------- Pike Dothan loamy sand
1 Boron did not increase or decrease yield statistically.
0.086
0.120
2,650
2,470
2,760
2,390
71 73
64 64
-I II ~- ' I I I \I I I-
I
of differences in soil moisture (boron deficiency is
more severe 
under droughty 
conditions).
The only appearance of boron deficiency in the
1971 experiments was on the Johnson farm, Table 1,
with a P-K fertilizer experiment in which boron was
omitted from the fertilizer. This field was in bahia-
grass from 1960 until 1971. Soil samples were taken
from all plots at harvest time and analyzed for avail-
able boron. The results are shown in Table 6 along
with the amount of hollow-heart in each plot. The
lower the level of available soil boron, the greater
the percentage of hollow-heart. In this particular
experiment, the "critical" boron level for deficiency
was less than 0.07 pounds per acre, a value below
the boron levels in either of the "boron experiments.
SUMMARY
The last 5 years of experimentation on farmers'
fields have shown the following: no yield increase
TABLE 6. SOIL-TEST BORON AND PERCENTAGE HOLLOW-HEART IN
A FERTILIZER EXPERIMENT ON FUQUAY LOAMY SAND IN
HENRY COUNTY (JOHNSON FARM)
Plot no.
4
5
7
4 -------------5 -------------------------6 
-----------------------------
. Soil-test B
Lb./A
0.090
0.070
0.058
0.060
0.066
0.066
0.046
0.060
Hollow-heart
Pct.
0.0
0.0
1.0
2.0
6.0
9.0
6.0
from directly-applied P and K fertilizers in 29 experi-
ments; gypsum in 37 experiments increased yield
only on soils with about 200 pounds per acre of
calcium or less; boron in 20 experiments was bene-
ficial in the drier years on soils very low in boron;
slag does not appear to be a satisfactory source of
calcium when applied at blooming time.