ioo THE WHEAT INDUSTRY 



winters. The effect of temperature is clearly 

 shown. Wherever wheat is produced on a large 

 scale, it makes its early growth during the cool 

 and moist season of the year and has a warm and 

 relatively dry season for ripening. 



Wheat requires only a moderate rainfall during 

 its growing period, a great deal less than some of 

 the other cereals. Thirty inches per year, prop- 

 erly distributed, is ample for any of the commer- 

 cial varieties. Some of the drought-resisting 

 wheats, such as Durum Wheat or Club Wheat, are 

 successfully produced where the annual rainfall is 

 even less than 15 inches. Commercial production 

 is most important in temperate regions of moderate 

 rainfall, and of relatively dry harvest seasons. 



The form in which the moisture is likely to 

 come, together with winter temperature conditions, 

 determines whether winter or spring wheat will 

 predominate in a given section. If winter tem- 

 peratures rarely drop to more than 20 below 

 zero, winter wheat is grown regardless of the 

 amount of prevalent snowfall, because such a 

 degree of cold does not prove injurious to the 

 hardier varieties. Where the temperature dur- 

 ing the winter. season falls much below the point 

 mentioned, unless a snow cover can be depended 

 upon to protect the ground, spring wheat is 

 grown. Thus because of the cold winters and 

 light snowfall, spring wheat is raised in North 



