476 Report oF THE HORTICULTURAL DEPARTMENT OF THE 
TABLE IX. 
MOISTURE PER ACRE IN TILLED AND Sop PLATS. 










1907. 1908. 
Soil depth. Plat. ——-- ----—________|_-__--- 
Amount of moisture. Amount of moisture. 
Per ct.| Tons. | Gallons. | Perct.{ Tons. | Gallons. 
TON 24 Peeoen.te ek te Tillage..... 12.20} 109.80} 26,330.9} 14.04} 126.36] 30,302.1 
SOU see Te oO 65.70| 15,755.4] 10.06 90.54) 21,712.2 
Difference. 4.90} 44.10] 10,575.5} 3.98) 35.82] 8,589.9 
Tel Bun ee eae fk Tillagwerns ss . 11.53] 152.64] 36,604.2| 13.57] 181.17] 43,446.0 
: SOG kieees 5 Seay 84.60} 20,287.7 9.37] 123.39] 29,589.9 
Difference..| 5.01] 68.04] 16,316.5] 4.20] 57.78! 13,856.1 
These figures substantiate what all admit in regard to other 
crops; that, in this climate, conserve it-and save it as best can 
be done, the seasonal rainfall on the average soil is not suf- 
ficient for the maximum development of the crop; indeed it is 
seldom sufficient for the optimum development of a crop. If 
then the rainfall is divided between two crops, grass and 
apples, one or both must suffer. 
The actual difference between the moisture content of the 
two plats has been shown by Table VIII and, summarized, in 
Table IX. It is now purposed to show what part the grass 
plays in causing this difference. Obviously the grass requires 
water. Can it be shown that if this water had not been used in 
growing grass it would have been used for apple tree growth 
and in the production of apples? 
Among others, Hellriegel and Wollny in Germany, Lawes 
and Gilbert in England, and King in Wisconsin, have pub- 
lished figures to show how many tons of water are required 
to produce one ton of dry matter in various crops. In Wis- 
-consin King® found that “the amount of water used ranges 

* Physics of Agriculture. By F. H. King, Madison, Wisconsin; 1901, 
p. 140. 
