50 THE BOOK OF WHEAT 



more highly developed must be the resisting qualities of wheat 

 to overcome them. By the law of the survival of the fittest, a 

 very detrimental condition in climate or soil develops in wheat 

 a correspondingly great power of resistance. This is the 

 scientific foundation of the importation of seed wheat. It 

 has been recognized and taken advantage of to a certain ex- 

 tent, but not as fully as might have been, and consequently 

 this point will merit subsequent mention. Advantageous im- 

 portations are well illustrated by the introduction of hardy and 

 drought and rust resistant varieties from the cold and the hot 

 and dry parts of Russia into sections of the United States 

 having a similar climate. A low altitude and an abundance of 

 moisture seem to produce softer wheats. 



Soil and Climate. Many characteristics of wheat are due 

 to the combined influences of soil and climate. Environments 

 that differ widely are characterized by peculiar varieties of 

 wheat varying in composition and physical appearance. Soft 

 wheat repeatedly sown on heavy, black, upland soil tends to be- 

 come hard, while hard wheat becomes soft after years of suc- 

 cessive planting on bottom lands. Experiments have shown 

 that the environment of Colorado affects the composition of 

 wheat by increasing its gluten content at the expense of the 

 starch content, while the environments of Oregon, California 

 and North Carolina have the opposite effect. A study of the 

 map 1 showing wheat districts will show the general effects of 

 climate and soil in the United States. Broadly speaking, the 

 hard, red wheats are found in the central, elevated plains, and 

 the grain becomes softer and of lighter color as either ocean 

 is approached. American, Russian and Algerian wheats have 

 about 12 per cent of moisture, while those of Europe have about 

 14 per cent. 2 As early as 1884 it was determined by chemical 

 analyses that the wheats of the Pacific coast in the United 

 States have a smaller percentage of albuminoids than those of 

 the rest of the country. In recent years there has also been a 

 gradual deterioration in the gluten content of North Dakota 

 wheats. The attention of the Department of Agriculture was 

 called to these deteriorations, which are due to the combined 

 effects of soil and climate, and extensive experiments were 

 carried on to determine the exact causes and afford relief. 



1 See p. 9. 



2 Girard & Lindet, Le Froment et sa Mouture, pp. 86-93. 



