Progress Report Series No. h8 
May 1951
AGRICULTURAL EXPERIMENT STATION
of The Alabama Polytechnic Institute, Auburn, Ala.
S .. *. E. V. SMITH, Director . . * * *
RESULTS of LINE and GYPSUM EXPERIMENTS with RUNNER 
PEANUTS
FRANKLIN L. DAVIS, Soil Chemist
C. A. ROGDEN, Superintendent*
For years it has been said that peanuts are hard on soil. This is true
if peanuts are harvested. When both peanuts 
and hay are removed, even great-
er amounts of nutrient elements are taken 
from the soil than when only the
nuts are harvested and the hay 
is returned to the land.
When both peanuts and hay are removed year after year, the 
plant food
elements are "mined" from the soil and lower 
yields result. This brings up
the question, "What soil amendments and fertilizers 
are needed to replace
these plant nutrient elements in the soil 
and how much is it necessary to
add to maintain yields or to increase yields on low-producing 
soils?"
Results of field experiments at the 
Wiregrass ubstation and with coop-
erating farmers give answers to this question, iesults of 
these tests show
specifically:
1. That peanuts grown and gathered from the same land year after 
year
"mined" the soil of its 
supply of calcium and potash.
2' That applications of phosphate, potash, and calcium (as either lime
or gypsum) restored yields.
3. That a low percentage of sound, mature kernels was a good indica-
tion of calcium deficiency in the 
soil.
4. That applications of either lime or gypsum (land plaster) to soils
producing low-grade or light, "poppy" peanuts 
increased yields where enough
potash had been supplied.
5. That applications of lime or gypsum always increased the percent-
age of sound mature kernels whenever 
the yield was increased.
Results of Experiments at Wiregrass Substation
The experiments at the Wiregrass Substation, 
near Headland, Alabama,
were located on an area that had been 
depleted by continuous cropping to
peanuts since 1932. The area is almost 
level so erosion is not a problem.
The yields from 1932 to 1936 ranged 
between 1,500 and 2,000 pounds of 
pea-
nuts per acre. Since 19hh, the 
yields have been less than 500 pounds 
per
acre. An experiment was started 
on this area in 19h9 to find out 
what fer-
tilizer materials were needed to 
restore yields? Seven of the main 
treat-
ments and their effects upon yields 
are shown in Figure 1.
* Wiregrass Substation, Headland, 
Alabama
FIGURE1. Average Yield of Peanuts- from Different Treatments on Depleted Soil
and Value'According to Grade, Wiregra-ss Substation, 1949-1950
TREATMENTS*
400
800 1200 1600
.Ptxyz:::
LK-I- X Y Z!I!I
..,so~os~ P K -- XYZ
and Vlue ccorlnfso 0 so odeVlr
0I ________
POUNDS OF PEANUTS PER ACRE, 2-YEAR AVERAGE
VALUE PER TON
ACCORDING TO
2000 GRADE
S 182.20
S 163930
$S170.00
$ 167.20
$S155. 10
$204.50
$200.69
* Treatments shown w ere as follows: P= 400 lb./a. of 18% superphosphate; F.< 200 lb./a.
of 60% muriate of potash; gypsum 500 lb/a.; lime = 1 ton/a.; and XYZ = a mixture in-
cluding 5 lb./a. of borax,, 10 lb./a. of zinc sulfate, 10 lb./a. of copper sulfate, 30
lb./a. of manganese sulfate, and 100 lb./a.. of magnesium sulfate.
FIGURE 2. Average Yield of Peanuts f ron Different Treatments on Depleted Soil,
Wi regras s Substation, 1950
TREATMENTS*
400 800 1200 1600 2000
NONE
I ME XYZ
. II
......................... LIE..KI......
nun: 
I 
M E + P 
K
HT HT: L I ME?+P K-IXYZYi:::::::Q
____0886_681_......................... ..W1a__agea__a____awes_1a.a.
POUNDS OF PEANUTS PER ACRE. 1.YEAR AVERAGE
*Treatments shown were as follows: P 400 lb./a. of 18%' superphosphate; K= 200
lb./a. of 60%o muriate of potash; lime 1 ton/a.; and XYZ = a mixture-including 5
lb./a. of borax, 10 lb */a. of zinc sulfate, 10 lb./a. of copper sulfate, 
30,lb./a.
of manganese sulfate, and 100 lb/a.,of magnesium sulfate.
(2)
w 1w. W VI V40, 5mom %
The 2-year average yields graphically compared in Figure I show that
200 pounds per acre of muriate of potash brought yields up to 797 pounds
per acre of peanuts and to 891 pounds per acre when applied with super-
phosphate. Evidently, this soil still contained a fairly good supply of
phosphate. Where lime or gypsum was added in addition to superphosphate
and muriate of potash, yields were 1,859 pounds per acre from gypsum and
1,943 pounds per acre from lime. Use of lime or gypsum 
also gave large
increases in grade and price per ton of peanuts. These results show that
both calcium and potash were needed to restore the yield of peanuts,
In 1950, another test was started to determine the effects of lime
alone. The treatments and the 1950 yields of peanuts from this test are
shown in Figure 2.
These results show that both lime and potash are necessary to restore
the yield of peanuts to approximately a ton per acre. The lime alone pro-
duced 762 pounds per acre and lime plus the minor element mixture produced
774 pounds per acre of peanuts. Thus, the reason for the 
greatly reduced
yields of peanuts on this soil appears to be that both lime and potash were
"mined" from the soil by continuous cropping. Therefore, both potash and
calcium were needed to restore peanut yields.
The need for both calcium and potassium by peanut soils has also been
shown by the results of more than 0 cooperative field experiments with
farmers.
Results of Cooperative Tests with Farmers
The experiments to measure the effects of applications of lime and
gypsum on runner peanuts have been conducted for 2 years in four counties
of the Wiregrass area of Alabama. The following treatments were repeated
four times in each experiment: (1) an untreated check, (2) lime at I ton
per acre, (3) gypsum at 00 pounds per acre, and (h) both lime and gypsum
at the 1-ton and 400-pound rates. The lime was applied at least 10 weeks
before planting and the gypsm (land plaster) was dusted on the peanut
foliage at early blooming stage. Yield data were obtained from 18 tests
in 1949 and from 26 tests in 1950. Of the 26 tests harvested in 1950, 12
were tests begun in 1949, while the other l were started in 1950.
Results of these cooperative tests show that insufficient potash sup-
plied by the soil and by the fertilizer applied limited the yields of pea-
nutso The yields obtained in 1949 from the plots that received neither
lime nor gypsum were not closely related to the soil content of exchangeable
calcium (usable form by plants). They were, however, definitely related to
the "available" potassium. The "available" potassium was considered to be
the sum of the exchangeable potash in the soil plus the potash supplied by
the fertilizer applied to the peanuts. On the plots where the calcium needs
of the peanuts were met by applying gypsum, the relation between yields and
available potash was highly significant. Thus, it would seem that adequate
amounts of potassium are also necessary if the full benefits of applica-
tions of lime or gypsum are to be obtained from peanuts, Both lime and
potash should be applied to many of these soilso
3
The results of a number of tests indicate that use of large amounts
of potash usually increases the 
yield on plots receiving lime or gypsum,
whereas yield and quality and shelling percentage of peanuts decrease
when calcium is deficient. Plenty of available potassium favors the
setting of nuts, but calcium is necessary for their development. Thus,
the production of light peanuts, or "pops," is a result of calcium de-
ficiency in the soil.
One of the objectives of this work is to determine the relationship
between yield of peanuts and calcium content of the soil. For this rea-
son, some tests were located on soils with a relatively high calcium con-
tent in order to determine the level of soil calcium below which peanuts
would respond to lime. The results have shown that the replaceable cal-
cium content of soils is a good index of the need for lime or gypsum.
Of the 26 tests harvested in 1950, 12 were on soils that had an
exchangeable calcium content equivalent to 710 pounds or less of calcium
carbonate or lime per acre. The average increase in yield of peanuts on
these 12 soils was 240 pounds per acre from lime, 283 pounds per acre
from gypsum, and 286 pounds per acre from both lime and gypsum. Of the
soils containing more calcium than the equivalent of 710 pounds of lime
per acre, only one gave an increase in yield of more than 200 pounds of
peanuts per acre, The average response of six soils having a medium
content of exchangeable calcium, namely between 720 and 900 pounds of
lime per acre, was 22 pounds of peanuts per acre from\lime, 90 pounds
from gypsum, and 44 pounds from both lime and gypsum. Eight soils had
an exchangeable calcium content equivalent to 900 pounds of lime or more
per acre. They produced average increases in yield of 20 pounds per
acre from lime, 74 pounds from gypsum, and 54 pounds per acre from both
lime and gypsum. Thus, all of the soils of low calcium content and one
of medium calcium content responded to lime and gypsum treatments. These
results are given in Table 1.
The results of these tests also show that the grade or percentage of
sound mature kernels is also a good indication of calcium deficiency in
the soil. Of the 18 tests harvested in 1949, three had less than 61 per
cent sound mature kernels on the no-lime or no-gypsum plots; the average
increase in peanut yields from gypsum was 484 pounds per acre. Seven
tests fell between 61 and 69.9 per cent sound mature kernels and had an
average increase in yield from gypsum of 133 pounds per acre. Peanuts
from the other eight tests graded 70 per cent and above, and the average
increase from gypsum was 26 pounds per acre.
The 1950 results are given in Table 2. Ten tests had less than 60
per cent sound mature kernels on the untreated check plots. The average
increases in yields were 258 pounds per acre from lime, 257 pounds per
acre from gypsum, and 304 pounds of peanuts per acre from both lime and
gypsum. Another 10 of these tests had percentages of sound mature kern-
els ranging between 60 and 70 per cent and yield increases of 62 pounds
per acre from lime, 141 pounds from gypsum, and 203 pounds from both
lime and gypsum. The other six tests had a percentage of sound mature
4
Table 1, Yields and Percentages of Sound Mature Kernels of Peanuts from Calcium
Treatments on Soils: of Different Calcium Levels,
26 Cooperating Farms, Southeast 
Alabama, 1950
Average peanut yields andpercentages sound mature
kernels from soils of different calcium levels
Treatment of lime
and gypsum Low Ca 
: Medium-low Medium-high
per acre 1/ soil 2/ : 
Ca soil 3/ Casoil/
Av. yield Av.Avv. yield Av. Av. yield Av.
per acre SMK per acre 
per acre SMK
Pounds Pct. Pounds Pct. Pounds Pct.
None .............. 1,361 589 1,51.3 ,97 62.0
Lime, 1 ton .......... 1,601 64.2 1,537 66.0 1,517 62.2
Gypsum, 400 lb. ...... 1i, 6 63.9 L,605 66.1 ,571 63.3
Lime, 1 ton and gyp-
sum, 400 lb ....... 1,647 65.2 1,559 66.3 1,551 
6.5
1/ Cooperating farmers used the same fertilizer and application rate on these
tests as they used normally for their peanut crops.
2/ Available (exchangeable) calcium in these soils 
(12 tests) are equivalent to
less than 710 pounds of 
lime per acre.
3/ Available calcium in these soils (6 tests) equal to a lime equivalent of 710
to 900 pounds-per acre.
4/ Available calcium in these soils (8 tests) equal to more than 900 pounds of
Time per acre.
Table 2. Yields of Peanuts and Percentages of Sound Mature Kernels from Calcium-
Treated Soils in Relation to Percentages of Sound Mature Kernels from
Untreated Soils, 26 Cooperating Farms, Southeast Alabama, 1950
SMK less than SMK 60 to 70 SMK 70 per cent
Treatment 
60 per cent 2/ 
per cent 2/ 
and over 3/
per
acre 1/ Average Average Average Average Average 
Average
yield/A SMK yie ld/A SMK yield/A SMK
Pound Pct. Pound Pct. Pound Pct.
None ............... 1,331 55.3 1,42 63.1 1,610 66.6
Lime, 1 ton ......... 1,589 61.8 1,504 64.4 1,607 67.1
Lime, 1 ton and
gypsum, 00 lb. ... 1,635 64.4 1,645 66.3 1,453 65i
1/ Each test was fertilized by the cooperative farmer the same as he normally
Tertilized his peanuts.
2/ Average of 10 tests.
_/ Average of 6 tests.
kernels on the untreated plots of 70 per cent and above* The average
increase in yield of these six tests was 94 pounds per acre from the
gypsum treatment; on the average, they showed a slight decrease in
yield from the limed plots. Thus, these results show that the grade or
percentage of sound mature kernels not only is a good indication of
calcium deficiency in the soil, but it is also a satisfactory index as
to whether lime or gypsum treatments will increase yields. On soils
that produce low grade,
- 
or light "poppy" peanuts, lime or gypsum treat
-
ments can be expected to result in yield increases if sufficient potash
is also supplied to the peanuts or -to the preceding crop.
Based on the results obtained in this study, it is probable that in
Southeastern Alabama between hO0 and 50 per cent of the soils need more
calcium and 75 to 90 per cent of them need more potassium for best pea-
nut yields, On many of the soils, a maximum response in yield to either
lime or larger applications of potash is dependent upon supplying the
other nutrient element.
6