A Study of Couorado Wheat 
53 
An application of 40 pounds of nitrogen was made to all of the plots 
that were treated to this manure at planting time and harrowed in 
just as the other fertilizers* But the plots receiving larger quantities 
received subsequent applications; those plots in Section 1800 another 
application of 40 pounds, and those in Section 1700 two other applica¬ 
tions of this amount, 120 pounds in all. The applications of nitrogen, 
as sodic nitrate, were m^de at intervals of about four weeks. All plots 
received an irrigation 12-16 June and four plots receiveid a second ir¬ 
rigation four weeks later, 11-13 July, in 1913 and 1914, but not in 1915, 
because the frequent light rains of this season kept the plants loaded 
with water. The characteristics of the weather, especially for 1913 and 
1915, have been stated, as also have the general crop-data, yield per 
acre, weight per bushel, and the ratio of straw to grains. An exam¬ 
ination of the figures giving this latter ratio will show that it is very 
abnormally high for the Defiance in 1914, and for all varieties in 1915. 
There were two causes operative in 1915 tending to bring this about. 
One of these causes was the presence of an unusually large amount of 
wild oats which increased the weight of the straw and for which no 
adequate compensation was made in the weight of the grain. This 
cause had nothing to do with this ratio for the Defiance in 1914. 
RUST INCREASED RATIO OF STRAW TO GRAIN ^ 
While the following statements may not belong in this place, their 
misplacement may emphasize the explanation offered for the appear¬ 
ance of the wild oats, namely, that we distributed them over the land 
with the water that was applied the preceding autumn preparatory 
to cultivating it. This water simply washed out the ditches in which 
these wild oats had collected and distributed them on our land. The 
other cause alluded to, acted in a more direct and effective manner in 
increasing the ratio of straw to grain. This cause was the rust that 
developed on the plants* This parasite practically killed the Defiance 
wheat grown with the application of nitrogen in both 1914 and 1915. 
The grain produced in these plots could scarcely be called grain at 
all, and such as we got weighed as low as 52 pounds per bushel in 1914, 
and 47 pounds in 1915. The yield being low—it fell to less than 9 
bushels in 1915—and the weight light, the ratiO' of straw to grain must 
necessarily be high. That this was wholly due to rust in 1914, and 
almost wholly so in 1915, there can be no doubt. The wild' oats may 
be mixed with the wheat and increase the weight of the straw, but do 
not cause shrunken, light-weight grains, which is a characteristic ef¬ 
fect of rust. 
I have tried to show that we have but little justification in think¬ 
ing that we can arrive at any certainty in regard to the real character- 
