74 
CoivORADo Experiment iSTATiON 
of yields, the weight per bushel, and the ratio of straw to grain given 
in this bulletin, shows that the check plots, except in the case of the 
Defiance, gave materially higher yields in 1914 than in 1913, and the 
weight per bushel was very high. In 1913, the Defiance check plots 
yielded 41.4, 40.6, and 41.3 bushels per acre, average 41. i bushels, 
weight per bushel 62.3 pounds; in 1914, the average yield was 31.i 
bushels, weight per bushel 56.7 pounds; in 1915, yield 19.5 bushels, 
weight per bushel 49.6 pounds. The Red Fife check plots averaged 
in 1913, 33.2 bushels, weight per bushel 64.0 pounds, anl in 1914, 47.2 
bushels> weight per bushel 63.7 pounds; in 1915, 32.6 bushels, weight 
per bushel 60.8 pounds. The Kubanka checks averaged in 1913, 34.2 
bushels per acre, weight per bushel 63.2 pounds, in 1914 the same plots 
averaged 47.8 bushels per acre and the weight per bushel was 64.9 
pounds; in 1915, 32.8 bushels and weight per bushel 62.3 pounds. The 
data given in the correlation table and the comparative yields and 
weights per bushel, given for the three seasons answer fully the ques¬ 
tions arising in connection with the succession of crops and exhaustion 
of the soil. The plants were well developed, the yields good and the 
weight per bushel, except in the case of the Defiance, above the aver¬ 
age in each of three years. 
The total rainfall in July, 1913, was 2.63 inches and the mean 
temperature 66*8 degrees F.; in 1914 the rainfall was 1.68 inches and 
the mean temperature 68.3 degrees F.; and in 1915 the rainfall was 
2.12 inches and the mean temperature 64.74 degrees F. 
In 1913 and 1914, we had but little cloudy weather, while in 1915 
it was prevalent. We had only ii days in July, 1913, which are re¬ 
corded as clear. The weather conditions in August were good, especial¬ 
ly in 1913 and 1914, but were not quite so favorable in 1915. In 1913, 
we had no rain in August prior to harvest, in 1914 we had 0.29 inches 
and in 1915, 0.57 inch. This 0.57 inch of rain did not interfere with 
our harvest, and it is a question whether it made our conditions any 
worse than they were already. I am quite certain that it would have 
done us no harm had it not been preceded by bad conditions in July, for 
the grain would have been so mature by this time that practically no 
injury would have resulted. We can, I think, with entire justice, neg¬ 
lect the weather conditions in August, not that I wish to assert that 
the one-half inch of rainfall in early August might not have injured 
our crop, but, as will appear later, bad conditions in the latter part of 
July, with very good conditioinis in early August, will produce very bad 
results, so I feel justified in neglecting the August conditions. Two 
things, of course, are here assumed as the causes of the bad results, 
one is the unfavorable weather conditions already mentioned, and the 
other is the condition development of the plant at this time. That 
this latter factor cannoc be too strongly emphasized is evidenced by the 
effects of these bad conditions on the Defiance wheat, compared with 
