42 



FUNDAMENTALS OF FRUIT PRODUCTION 



Effects of Early and Late Seeding. — Cover crops use considerable 

 water in their growth. A good cover crop probably produces at least 

 14, ton of dry matter per acre involving the transpiration of from 2 to 4 

 acre-inches of water. However, the cover crop makes its demand for 

 water upon the soil during the fall, winter and spring months — a time 

 when there is most likelihood of an abundant water supply and conse- 

 quently when the trees are not so likely to be injured by the draft of the 

 cover crops. It is true that cover crops are usually seeded in late July or 

 in August, but their growth is so limited before the middle or end of 

 September that they compete but little with the trees for either nutrients 



Table 23.- 



-Percentage of Soil Moisture in Bare Ground and Under Cover 

 Crops in Early November After a Drought^s 



Table 24. — Percentage of Soil Moisture for Each Cover Crop from Nov. 1, 

 1905, to Feb. 17, 1906, and the Average for Three Determinations" 



Crop 



Percentage of moisture in soil to depth of 30 inches 



Nov. 

 21-22, 1905 



Jan. 

 2-3, 1906 



Feb. 

 16-17, 1906 



Average 



Cowpeas 



Soy beans 



Crimson clover 



Hairy vetch 



Oats 



Canada peas 



Oats and Canada peas 



Rye 



Check 



Millet 



Rape 



Turnip 



Turnip and rye 



Hairy vetch and Canada 



peas 



Oats and crimson clover. . . 

 Cowpeas and crimson clover 



Average 



17.7 

 18.9 

 18.6 

 17.4 

 17.0 

 17.7 



17.3 

 17.6 

 18.1 



17.1 



24.5 

 23.2 

 23.7 

 24.6 

 22.7 

 21.4 

 25.5 

 22.5 

 22.4 

 23.4 

 24.0 



23.5 



21.9 

 23.4 

 23.4 

 20.5 

 21.2 

 18.8 

 22.0 

 21.7 

 20.4 

 20.6 

 21.7 

 19.3 

 22.5 



19.2 

 20.0 

 26.7 



21.5 



21.7 

 21.9 

 21.9 

 20.8 

 20.3 

 19.3 

 21.1 

 20.2 

 19.7 

 20.0 

 20.7 



20.7 



