TRITICUM 107 



and Bluestem. Turkey and Kharkov are the chief hard 

 winter wheats, and Kubanka the most important durum 

 wheat. On account of its highly glutenous character, durum 

 is used extensively in the manufacture of macaroni and 

 vermicelli. The flour of this hard, glutenous wheat is being 

 mixed with that from the softer wheats, and the result is a 

 flour of excellent bread-making qualities. 



Much emphasis has been placed upon the great influence 

 of climate upon the composition, hardness and quality of 

 wheat. In fact, it is claimed, that the soil has Httle or no 

 effect upon these characters. In general, a hot, dry climate 

 produces a fine-stemmed plant the grain of which is hard, 

 glassy and rich in nitrogen, while a cool, moist climate pro- 

 duces a coarser-stemmed plant the grain of which is relatively 

 soft, mealy and poor in nitrogen. Headden, however, has 

 been able to produce starchy and flinty kernels at will in the 

 same variety growing under identical climatic conditions, by 

 controlling the ratio of nitrogen to potassium. An abund- 

 ance of nitrates produced a flinty grain, while a scarcity of 

 nitrates in proportion to potash gave a starchy, mealy 

 grain. This work establishes the fact that the soil, as well 

 as the climate, is a factor in determining the quality of 

 wheat. 



Milling of Wheat. — The wheat is first thoroughly cleaned 

 and scoured to remove sticks, straw, fine dust particles, and 

 hairs of the brush. It is then slightly moistened with water, 

 in order to prevent the pericarp from grinding up fine. This 

 is known as tempering. Then comes the process of breaking. 

 This consists in removing the bran coats and embryo from 

 the endosperm, and the gradual reduction of the latter to 

 finer and finer particles. In this process the grain is passed 

 between successive pairs of corrugated iron rolls. The prod- 

 uct of each set of rolls is sifted, and the particles are graded 



