20 BULLETIN 1173, U. S. DEPARTMENT OF AGRICULTURE. 
G13 19/9 I/WE AWC. 19U7 I9/8 IBID (920 dae 
15 
LARLY SPRING PLOWING 
LATE SPAING FLOWING = ——————— 
LARLY SOMMER PLOMING = —.—-—-—-—- 
Fic. 14.—Annual and aveete acre yields, in bushels, of winter wheat in varying numbers of years at Moro, 
Oreg., Lind, Wash., Nephi, Utah, when grown after summer fallow for which the land had been 
plowed in early sprig. inte spring, ee early summer, respectively. 
