THE SMALL GRAINS 205 



(d) It can be easily transformed into a light, appetizing, 

 wholesome, almost perfect food for human beings. 



(e) Valuable foods for domestic aiiimals are prepared 

 from those portions of the grain which man does not use 

 for white flour. 



138. Climatic Conditions Favorable for the Growth of 

 Wheat. — In North America, the greater part of the 

 wheat crop is produced where the temperature in January 

 is below freezing. Wheat is grown in California and other 

 portions of the country where cold winter weather does 

 not prevail, but on the whole, the cultivation of the crop 

 is moving northward. The immense wheat fields of Al- 

 berta and Saskatchewan in Canada show this to be true. 



The best wheat is grown where there is a long, cool 

 spring, followed by a moderately dry, sunny summer 

 season while the grain is ripening. 



139. Winter and Spring Wheat. — There are two 

 general classes of wheat : that which is sown in the fall, 

 called winter, or fall wheat; and that which is sown in the 

 spring. In general, winter wheat, which comprises from 

 sixty to seventy per cent of the total wheat crop of the 

 United States, is grown south of the forty-second parallel, 

 while most of the spring wheat is grown north of that line. 



Winter wheat is more productive than spring wheat, 

 as a rule, in those sections where both may be grown; 

 and owing to the introduction of hardier varieties, it is 

 being grown, like corn, farther north each year. 



140. Systems of Rotation. — Throughout the newer 

 regions of the great wheat belt, wheat follows wheat 

 year after year. The virgin soil, modern cultivating 

 and harvesting machinery, the comparatively low price 

 of land, the satisfactory returns and the scarcity of labor 



