78 
Research Bulletin No. 5 
Table 31. — Water required to produce one pound of dry matter 
of various crops. 
Crop 
Year 
Average 
per cent water 
in upper 
6 feet of soil 
it water used from 
used from soil — 
per acre 
Precipitation during 
growing season, inches 
vater available to 
rom soil and pre- 
dion — tons per acre 
sitter produced, 
ds per acre 
i of water required 
me pound of dry 
er 
Seeding 
Harvest 
p 
03 _ 
S3 
™ p a 
si 
Q 
C In 03 
Spring 
wheal 
1908 
1909 
1910 
1912 
11.8 
13.6 
12.6 
IRQ 
11.3 
13.1 
10.5 
8 ^ 
.5 
.5 
2.1 
8 4 
52.2 
52.2 
219.5 
878 9 
12.8 
12.1 
6.2 
7.6 
1505.3 
1422.5 
926.3 
1 740 0 
3980 
3530 
1350 
9^80 
756 
806 
1372 
lolO 
Corn 
1908 
1909 
1910 
1912 
13.0 
11.7 
13.9 
16.8 
8.6 
12.8 
11.1 
12.3 
4.4 
.9 
2.8 
4.5 
460.0 
262.7 
470.4 
14.4 
14.2 
5.4 
6.8 
2090.8 
1516.4 
898.6 
1240.6 
4380 
5000 
2950 
5120 
955 
606 
610 
485 
Cane 
1908 
1909 
1910 
1911 
1912 
15.4 
14.3 
13.3 
10.3 
13.9 
7.9 
7.3 
7.3 
7.5 
8.9 
7.5 
7.0 
6.0 
2.8 
5.0 
784.1 
731.8 
627.2 
313.6 
522.7 
6.6 
8.1 
2.9 
7.0 
7.2 
1534.9 
1653.7 
952.3 
1106.4 
1338.1 
10600 
8740 
7000 
2200 
5640 
290 
378 
272 
1000 
475 
Winter 
wheat 
1908 
1909 
1910 
1911 
1912 
16.2 
12.1 
15.0 
11.4 
12.3 
8.2 
10.3 
10.0 
8.4 
8.0 
7.0 
1.8 
5.0 
3.0 
4.3 
731.8 
313.6 
971.2 
418.2 
599.4 
13.6 
15.8 
10.9 
7.7 
15.2 
2277.7 
2103.0 
2105.7 
1292.5 
2319.7 
7260 
6768 
5436 
2448 
2520 
627 
621 
775 
1056 
1841* 
* There was a heavy run-off when the snow melted this spring, and 
this is charged to the crop. 
WATER REQUIRED TO PRODUCE ONE POUND OF DRY MATTER 
OF VARIOUS CROPS. 
In computing the amount of water required to produce a 
pound of dry matter, we have taken the water used from the 
upper six feet of soil for each crop except winter wheat. With 
winter wheat we used a greater depth in order to include its 
entire feeding range. The difference in water content of the soil 
at seeding and harvest dates is figured as the water used from 
the soil. The total rainfall from seeding date to harvest date is 
