24 ORCHARD GREEN-MANURE CROPS IN CALIFORNIA. 
makes less growth during the winter season than the common vetch, 
and this has prevented its larger use for green manuring. Extensive 
experimental tests in comparison with common vetch, as well as 
practical tests made by orchardists, show the same results. 
While hairy vetch does not make a good winter growth, when the 
warmer weather of the latter part of winter and early spring comes, 
it makes a very vigorous start and,if left to develop fully, a heavier 
growth than common vetch. It also stands more dry weather without 
injury, and where a late spring crop is wanted it is very desirable. 
The handling of the crop is the same as with common vetch. From 
45 to 50 pounds of seed per acre should be used in seeding. 
INDIAN MELILOT. 
Indian melilot (Melilotus indica) is quite common in waste places 
throughout the orchard sections of southern California and for a 
number of years has received some attention as a green-manure 
crop. However, it has never been used except in a very limited or 
experimental way, and this experience indicates that it has but 
very little value in orchard work in California. . 
The winter growth of melilot is about like that of bur clover, and, 
like that crop, its best growth is not made until too late in the 
winter to be turned under in February. The only place in California 
where melilot seems likely to prove at all valuable is on the very 
sandy soils, to which it is quite well adapted and on which it is often 
hard to get a stand of other green-manure crops. 
SUMMER GREEN-MANURE CROPS. 
The question is sometimes asked whether it is advisable to grow a 
summer green-manure crop as well as a winter crop, thus enabling 
one to add two crops a year to the soil instead of one. Where water 
for irrigation is available there is no difficulty in doing this. How- 
ever, the practice is not to be advised except under very exceptional 
conditions. The enormous quantity of water used by a green-manure 
crop in its growth makes it decidedly objectionable for summer use 
in an orchard, where all the water available is usually needed for the 
orchard crop. | : 
The growing of a summer green-manure crop also necessitates the 
discontinuance of cultivation of the soil, which except on the most 
open soils would be more or less detrimental if continued for a long 
period. There may be instances, however, where it is desirable to 
build a soil up as rapidly as possible. In such cases a summer green- 
manure crop may be used to advantage. For this purpose the 
Whippoorwill variety of cowpea has been found the best of any crop 
tested. 
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