' THE SMALL GRAINS 213 



The inner portion of the grain is used for flour, the 

 wheat yielding about seventy per cent of this product. 



The outer coat of the grain is made into bran, a coarse, 

 Ught product, which is extensively used as a feed for stock. 

 The embryos and the layers just beneath the bran are 

 mixed usually with the bran itself, forming a product, 

 known as wheat middlings. These portions of the grain 

 are rich in protein, and therefore have a high feeding 

 value. (Section 94.) 



If no part of the grain is removed after grinding, the 

 product is known as Graham flour; if the coarser parts 

 are removed, it is called whole wheat flour. 



Experiments have shown that the percentage of the 

 different flours that is digestible when used as food is as 

 follows : 



White flour 90.1 % 



Whole wheat flour . 85.5 % 



Graham flour 80.7 % 



Thus we see that a higher percentage of the white flour 

 is digestible than of the others, partially because of its 

 finer state of division, but also because most of the in- 

 digestible parts of the kernels have been removed. Be- 

 cause of this greater digestibility, bread from white flour 

 will doubtless long remain, as it is at present, the choice 

 of the great majority of the people. 



Oats 



146. Oats a Cool Climate Crop. — The oat plant is a 

 short season plant. It requires a smaller amount of 

 heat for its development than does barley or wheat; 

 and for this reason, it is grown most successfully in the 

 cooler climates. In Scotland, Norway, Sweden and in 

 Canada, large quantities of oats are grown. The average 



