24 
BULLETIN 1340, IT. S. DEPARTMENT OF AGRICULTURE 
the former station showed that there should be enough moisture in 
the soil at the time of planting to sprout the seed and maintain the 
crop in a vigorous condition to the beginning of the jointing stage. 
By plowing the ground in the fall, leaving it rough during the winter 
and cultivating and seeding early in the spring, there is usually 
enough moisture in the soil in that locality to meet this requirement. 
If, however, the ground is not plowed in the fall, the season late or 
dry, a medium irrigation may be necessary before planting. The 
results also showed that the greatest need for water occurred be- 
tween the jointing and the soft-dough stages. A heavy irrigation 
about the time of early jointing produced a large head and supplied 
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JUNE 
6 12 18 24 
JULY 
5 17 23 2S 
AUGUST 
Fig. 12. — Water used during various stages of growth as determined at Pullman, 
Wash., in 1911 and 1912. Average of 4 tanks, each of 3-1/7 sq. ft. art a 
sufficient moisture for subsequent growth. When water was with- 
held during this period and applied after the soft-dough stage, the 
effect was injurious rather than beneficial. The best yields were ob- 
tained by maintaining a fairly constant soil moisture content from 
the time of seeding until the hard-dough stage was reached. 
The results obtained in growing cereals at the substation of the 
Idaho Agricultural Experiment Station at Gooding likewise showed 
the advantage in crop yields of an adequate supply of moisture until 
the hard-dough stage was reached. When the crop was not irrigated 
during its critical stages of growth, the quantity of the yield was 
reduced and its quality impaired. No subsequent waterings could 
remedy the damage done. In many cases the application of water 
three weeks or less before harvest time tended to lodge the grain 
