COMPOSITION OF WHEAT 45 



Carleton believes that localities with black soils (high in organic 

 matter) and extreme climatic variations are most favorable for 

 the production of high protein content. William E. Edgar says : 



" Gradually as the northwestern States have become cultivated the original 

 hard wheat has grown scarcer. WTieat raised on virgin lands has a peculiar 

 strength lacking in that produced in older fields. It is capable of improving the 

 character of other wheat blended with it when the mixture is made into flour." 1 



Lawes and Gilbert, in an elaborate series of analyses of wheats 

 grown on unmanured and variously manured plats during twent}^ 

 seasons, have shown the variation in composition of wheat to be 

 much more influenced by season than by manuring. There was 

 very little variation in the mineral composition of the wheat grain 

 accorded to manuring except in cases of abnormal exhaustion. 

 Commenting upon the significance of the facts presented, the 

 authors say : 



" The character of development of a crop left to ripen, depends very much more 

 upon season than upon manuring. Indeed, if one crop (of wheat for example) grows 

 side by side with another of exactly the same description, but j-ielding imder the influ- 

 ence of manure t-nice the amount of produce, and both under such conditions of 

 season that each fully and normally ripens, the composition of the final product, 

 the seed, will be very nearly identical in the two cases. In other words, there is 

 scarcely any diff^erence in the composition of the truly and normally ripened seed. 

 But, as variations of season affect the character of development, and the conditions of 

 maturation, there may obviously be, with these, verj- wide differences in the com- 

 position of the product. The wide range in the composition of the ash of the grain, 

 which the table shows according to season, represents in fact a corresponding 

 deviation from the normal development." 2 



The climatic condition which seems most uniformly to affect 

 the composition of the grain is the length of season of growth. 

 The shorter the season of growth, the higher the percentage of 

 protein and the lower the percentage of starch. Doubtless the 

 shorter the season of growth, the smaller the grain. 



It does not follow^ that strains may not be selected which will 

 contain high per cents of protein and at the same time produce 

 more protein per acre, although the facts stated above suggest 

 that difficulty may be found in doing so. 



1 The Stor)' of a Grain of Wheat, p. 126. New Vork, D. Appleton & Co., 1903 



2 Lawes and Gilbert on the composition of the ash of wheat-grain and wheat 

 straw, p. 8. 



