26 



hold its own. Sometimes this change is rendered necessary by condi- 

 tions which are beyond the power of man to modify. As an example, 

 No. 10 of Professor Blouut's wheats, known as "Oregon Club," a white 

 variety from Oregon, has been deteriorating every year since it has been 

 grown in Colorado, whereas if the seed had been supplied every season 

 directly from Oregon the quality would probably have remained the 

 same. In extension of this illustration, the fact may be mentioned that 

 annual renewal of the seed from a desirable and favofable source often 

 makes it, possible to raise cereals where otherwise the climatic condi- 

 tions would render their cultivation impossible through rapid reversion. 

 This is particularly the case with extremes in latitude, the effect of 

 which is found not so much upon the composition of the crop as on 

 the yield and size of the grain. In the South the warmer climate, to- 

 gether, of course, with poorer soil and cultivation in many instances, 

 reduces the yield. The average in different States is given by Mr. 

 Dodge as follows : 



Yield per acre of wheat. 



It must be remembered, however, that three quarters of the wheat 

 crop has been produced in the ten States of Illinois, Indiana, Ohio, 

 Michigan, Minnesota, Iowa, California, Missouri, Wisconsin, andPenu-, 

 sylvania, and that a State like Minnesota must not be considered as 

 furnishing the largest part of the supply merely because wheat is the 

 prevailing crop in that State. 



Having shown the conditions under which unfavorable and favorable 

 variations occur, it is hoped that these investigations will be the means 

 of aiding those who are engaged in the improvement of the yield and 

 quality of the crop of our country. 



It seems proper in this place to allude also to the immense amount of 

 the best food elements of our soils which are yearly being taken from 

 the farm and exported from our ports in the shape of nitrogen and the 

 mineral constituents of the grain, the loss of which is continually ren- 

 dering our wheat lauds poorer and forcing the cultivation into new 

 parts of the country where the soil is still of virgin richness. If grain 

 is sold off the farm the loss of nitrogen and minerals must be replaced 



