19 
SEVEN YEARS IN FIELDS A, B, AND C. 
Number 
of 
Plat 
Yield in 
Bushels of 
Shelled 
Corn per 
Acre 
I 
Yield of Stover in Pounds 
per Acre 
Average Increase in 
Bushels of Shelled 
Corn per Acre Due to 
Fertilizer 
Average Increase in Lbs. 
of Stover per Acre Due 
to Fertilizer 
Value of Increase with 
Corn at $0.70 per 
Bushel and Stover at 
$8.00 per Ton 
Cost of Fertilizer per 
Acre 
Value of Average An¬ 
nual Increase of Corn 
and Stover Over Cost 
of Fertilizer 
Value of Average An¬ 
nual Increase of Corn 
Alone (Not Valuing 
Stover) Over Cost of 
Fertilizer 
1908 
Ave. 
1903 
1904 
1906 
1908 
Ave. 
1 
52-4-8 
19.5 
1785 
$_ 
$_ 
$ 
$ 
3 2 -l-l 
20.1 
1712 
.6 
—73 
.13 
2.08 
—1 95 
—1 66 
42-2-2 
25.7 
"J 
2003 
6.2 
291 
5.50 
1.05 
4.05 
3.29 
(52+14 2 )- 
4-8 
19.1 
1 
1751 
62-3-3 
19.2 
_J 
1781 
.1 
—113 
— .38 
.23 
— .61 
— .16 
(52+14 2 )- 
(4+11)—8 
18.5 
1700 
72-5-4 
37.3 
2633 
18.8 
901 
16.89 
3.13 
13.76 
10.03 
( 52 + 142 )- 
(4+ll)-8 
17.9 
1650 
82-6-5 
19.5 
1801 
1 5 
151 
1.65 
2.31 
— .66 
—1.26 
(52+142)- 
_ 
(4+11)—8 
16.8 
1549 
102-8-6 
35.9 
2308 
19.1 
1069 
17.65 
3.36 
14.29 
10.01 
( 52 + 142 )- 
(4+11)—8 
16.1 
1523 
92-7-122 
3.26 
2538 
16.5 
1015 
15.61 
1.28 
1 “ 
14.25 
10.27 
54_1 8 2_ 8 2 
17.6 
1 _ 
1485 
4 4 —14 2 —72 
16.1 
1443 
—1.47 
—42 
—1.19 
.63 
—1.82 
—1.66 
64— 152—92 
31.8 
i. 
j_ 
2211 
14.2 
726 
12.84 
3.99 
8.85 
5.95 
did not affect the yield, as the average yields for the unfertilized potash plats are near the same. 
4 and 11, and 5 2 and 14 2 respectively. It has been assumed that there is a uniform increase or decrease in the 
between checks. 
Phosphoric Acid and Potash, P Ii (Plats 9 2 , 7 and 12 2 ). 
Phosphoric acid and potash combined gave increased yields on all the 
plats in the three fields, the average annual increase for four years 
in Field B being 15.2 bushels of corn per acre, for two years in 
A 21 bushels, and for one year in Field C 12.5 bushels, or an 
average for the seven years in the two fields of 16.5 bushels, worth 
$10.27 over cost of fertilizer on basis of com alone, or $14.25 on 
basis of corn and stover. From this it is seen that potash added to 
phosphoric acid has increased the yield of corn 10.3 bushels more 
than phosphoric acid alone, at a profit of $6.98 over cost of fer¬ 
tilizer, showing that potash was effective in corn production on this 
soil when used in connection with phosphoric acid, but valueless when 
used alone. 
