EFFECT OF SOIL FACTORS ON WATER REQUIREMENT. 
27 
Table XV. — Effect of different soils on the water requirement of com, 1 according to 
King (1905, pp. 193-194.) 
Location. 
Soil. 
Duration. 
Evapora- 
tion per 
square foot 
of soil 
surface 
per day. 
Water re- 
quirement. 
Goldsboro N. C 
Norfolk sandv loam 
Days. 
97 
120 
12S 
120 
Pounds. 
1.1 
.98 
. 790 
. 938 
387 
Norfolk sand 
1,152 
Hagerstown clay loam 
Janesville loam. 
474 
330 
The variety of corn used was Iowa Goldmine. 
VON SEELHORST S EXPERIMENTS. 
Von Seelhorst (1906) measured the water requirement of rye and 
potatoes in open pots, using loam and sand. The results (Table 
XVI) show that rye has a somewhat lower requirement in loam 
than in sand. With potatoes, however, the results were reversed, 
the sand giving a slightly lower water requirement. The data are 
too meager to be conclusive. 
Table XVI. 
-Effect of soil type on the water requirement of rye and potatoes at Gottingen, 
according to Von Seelhorst. (1906, p. 316). x 
Plant. 
Sand. 
Loam. 
Mean dry 
matter. 
Water re- 
quirement. 
Mean dry 
matter. 
Water re- 
quirement. 
Rve 
Grams. 
300 
i 103 
480 ±15 
00±0 
Grams. 
700 
4,737 
375 
66 
i The water requirement of potatoes is based on the green weight. Three determinations were made 
with each crop for sand, one determination for loam. 
WIDTSOE S EXPERIMENTS. 
Widtsoe (1909) has measured the water requirement of corn and 
wheat at Logan, Utah, using four types of soil. Pots 24 inches in 
diameter and 30 inches high were employed. The College loam and 
Sanpete clay types were productive soils, while the sand and clay 
types were nonproductive. The experiments extended through a 
period of four years. The increased water requirement of crops 
when grown in nonproductive soils is clearly shown in the results, 
a summary of which is given in Table XVII. 
285 
