456 
Journal of Agricultural Research 
Vol. XXX, No. 5 
Table IV .—Amount of potassium in drainage water, teachings, and soil extracts 
Pot 
Treatment (pounds 
Experiment 1 (field pots)—potassium in pounds 
per 2,000,000 pounds of soil 
Experiment 2 (green¬ 
house pots)—potas- 
i sium in pounds per 
2,000,000 pounds of 
! soil 
No. 
per acre) 
De¬ 
cem¬ 
ber 
Janu¬ 
ary 
and 
Febru¬ 
ary 
March 
and 
June 
Total 
for five 
months 
Soil 
ex¬ 
tracts 
Total 
water- 
soluble 
potas¬ 
sium 
Leach¬ 
ings 
Soil 
ex¬ 
tracts 
Total 
water- 
soluble 
potas¬ 
sium 
1 
Control_ 
24.1 
35.9 
120.8 
180.8 
244.4 
425.2 
27.5 
156.3 
183.8 
2 
-do_ 
25.0 
22.9 
202.7 
250.6 
231.5 
482.1 
56.1 
157.2 
213.3 
Average_ 
24.5 
29.4 
161.7 
215.7 
237.9 
453.6 
41.8 
156.7 
198.5 
3 
Uninoculated sulphur 
186__ 
26.8 
32.8 
160.7 
220.3 
278.1 
498.4 
80.0 
176.0 
256.0 
4 
_do_ 
24.0 
25.4 
195.8 
245.2 
262.1 
507.3 
82.5 
169.8 
252.3 
Average_ 
25.4 
29.1 
178.2 
232.7 
270.1 
502.8 
81.2 
172.9 
254.1 
5 
Inoculated sulphur 189 
25.0 
27.1 
181.0 
233.1 
254.0 
487.1 
75.6 
182.4 
258.0 
6 
.do__ 
21.6 
24.5 
181.1 
227.2 
242.8 
470.0 
74.5 
171.2 
245.7 
Average... 
23.3 
25.8 
181.0 
230.1 
248.4 
478.5 
75.0 
176.8 
251.8 
7 
Uninoculated sulphur 
1000.... 
25.7 
31.9 
215.9 
273.5 
302.2 
575.7 
131.3 
226.7 
358.0 
8 
.do.... 
25.3 
23.5 
227.9 
273.5 
287.8 
561.3 
131.9 
201.6 
333.5 
Average_ 
25.5 
27.7 
221.9 
275.1 
295.0 
568.5 
131.6 
214.1 
345.7 
9 
Inoculated sulphur 
1015_ 
28.7 
24.5 
268.1 
321.3 
285.4 
606.7 
131.4 
234.4 
365.8 
10 
-do__ 
26.3 
31.4 
235.3 
293.0 
298.2 
591.2 
113.4 
200.2 
313.6 
Average_ 
27.5 
27.9 
251.7 
307.1 
291.8 
598.9 
122.4 
217.3 
339.7 
11 
Gypsum 1000_ 
38.7 
54.6 
106.9 
200.2 
241.1 
441.3 
60.8 
172.2 
233.0 
12 
_do__ 
41.1 
58.9 
114.1 
214.1 
233.1 
447.2 
84.6 
183.3 
267.9 
Average_ 
39.9 
56.7 
110.5 
207.1 
237.1 
444.2 
72.7 
177.7 
250.4 
strikingly brought out by the data 
given for the high sulphur treatments. 
In this connection Ames 5 suggested 
that the liberation of potassium was 
brought about by salts formed rather 
than by the direct action of acidity, 
developed from nitrification and sul- 
phofication, on insoluble potassium 
compounds. That this assumption 
holds true for these experiments will 
be shown later, when the hydrogen-ion 
concentrations of the soils are con¬ 
sidered. 
The inoculated and uninoculated 
sulphur treatments showed practically 
the same effect in liberating the in¬ 
soluble soil potassium. 
The data given for the analyses of 
the drainage water from the soils 
treated with gypsum indicate that for 
the first three months gypsum caused 
an increase in water-soluble potassium, 
but, on the other hand, the data for the 
total water-soluble potassium show 
that gypsum slightly decreased the 
amount of potassium going into solu¬ 
tion. A correct interpretation of the 
effect of gypsum on soil potassium in 
experiment 1 is made impossible by 
the seemingly high analysis reported 
for the control soil No. 2 for the March 
and June drainage. The data given 
for experiment 2 show that under 
greenhouse conditions gypsum brought 
about a distinct increase in the amount 
of potassium found in the leachings 
and also in the soil extracts. 
EFFECT OF SULPHUR AND GYPSUM ON 
CALCIUM 
Tottingham and Hart 6 summed up 
their work on sulphur and sulphur 
composts with the statement that 
“ adequate consideration of the use of 
sulphur as a fertilizer must recognize 
its tendency to deplete the stock of 
« Ames, J. W. solvent action of nitrification and sulfofication. Ohio Agr. Exp. Sta. Bui. 351, 
p. 221-257. 1921. 
e tottingham, W. E., and Hart, E. B. sulfur and sulfur composts in relation to plant nutri¬ 
tion. Soil Sci. 11: 49-65, illus. 1921. 
