36 BULLETIN 157, U. S. DEPARTMENT OF AGRICULTURE. 



TIME OF HARVESTING WINTER WHEAT. 



During the period from 1909 to 1912, inclusive, a test of the effect 

 of the time of harvesting upon the yield and quality of winter wheat 

 was conducted. The milling and chemical tests of the wheat were 

 made by the division of chemistry of the Utah station, but the data 

 are not available at this time. Only the data on yield will be pre- 

 sented here. 



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Fig. 19.— Graphs showing the average seasonal decline in the percentage of moisture in each of the 

 upper 6 feet of soil, as found in the spring-cultivation tests of winter wheat at the Nephi substation, 

 1909 to 1913, inclusive. 



The four plats used in this test lay side by side and were treated 

 uniformly up to and subsequent to the time of harvesting. One of 

 these plats was harvested when the kernel was in the green-dough 

 stage and one each week thereafter until all were harvested. In this 

 way the grain was cut in four different stages of maturity, namely, 

 green dough, hard dough, fully ripe, and overripe. The annual and 

 average yields of the plats for the four years are given in Table XV. 



