240 



BULLF.TIX 89 



Fig. 6. — Alfalfa used as a cover crop in the Blaisdell citrus orchard 



', .^ 



Fig. 7. — <.'o\i'r criip of cnw i)eas planted in rows in Hill's citrus orchard on Yuma 

 Mesa. The land between the trees had received no water or cultivation up to the 

 time the trees were planted 



