lOO 
Coi^ORADo Experiment Station 
in the individual samples, they serve to show that the different seasons, 
including all the factors, made but little difference in the average per¬ 
centages of these elements in the grain, though the development of the 
kernels and their composition, especially in regard to nitrogen, was 
very different. While I believe, and have so stated, that very small 
differences expressed in percentages of air-dried grain, very probably 
have a big significance in regard to the properties of the wheat, and in 
relation to the effects of fertilizers, and perhaps, also of the seasons. 
I doubt, however, that we have any data which can be properly so inter¬ 
preted, still the above averages justify the inference that the relative 
amounts of ash were not affected greatly by the different conditions 
prevailing during the three seasons; in other words, the whole develop¬ 
ment of the plant moved forward in the same manner and relative 
measure up to the time that the rust interrupted the transfer of matter 
to fill out the grain. We have no analyses' of the plants, giving the ' 
ash constituents at such periods in their development that we can use 
the results in this connection. This is to be regretted, for had we analy¬ 
ses representing plants before and after this period of rapid transfer, 
it might give us some further useful data. 
These results are in close agreement with the conclusions of 
Brenchley and Hall, who say: “For the filling of the endosperm, each 
plant possesses as it were a special mould, and continually moves into the 
grain uniform material cast into that mould, possiessing always the same 
ratio of nitrogenous to non-nitrogenous materials and ash.”* 
THE EFFECTS OF IRRIGATION 
Our object in this work was to ascertain what we may consider 
characteristic of Colorado wheats and the factors to which this may be 
due. I have presented the crop of 1913 as probably the most nearly 
normal wheat that we have grown up to the present time, and I have 
justified myself in doing so by presenting the abnormal characteristics 
of the crops for 1914 and 1915, and the causes for the same. One of 
the factors which enters into our problem is the effect of water, partic¬ 
ularly when applied as irrigating water. This question has already 
occurred in the consideration of the causes for the inferior quality of 
our 1914 and 1915 crops. In this connection I treated it in the most 
summary manner, principally because it is a definite and distinct prob¬ 
lem. During the seasons of 1913 and 1914 I selected four plots to 
whichj I applied a second irrigation four weeks subsequent to the first 
one and equal in quantity, namely, I aimed to apply i acre-foot at each 
irrigation and to see what effects it produced upon the yield and char¬ 
acter of the grain. 
* W. E. Brenchley and A. B. Hall, “Development of the Grain of Wheat,” 
,Tournal Aprricnltural Science, Vol. 3, Part 2 , p. 215; also Rothamsted 
Memoirs, Vol. 8. 
