CHAPTER XX 



FIELD CROPS 

 SEED CROPS 



THE most important seed crops are the cereal grains 

 like wheat, rye, barley, and rice, whose seeds are used 

 for human food as well as for stock feed. 



Wheat is the most highly valued of the grain crops, 

 because it alone makes good "light bread." That is 

 because wheat contains a stringy, tough substance 

 called gluten, which sticks to the teeth when you chew 

 soft wheat. Gluten is best shown when made from 

 wheat flour, as in the experiment explained below. 

 Of the other grains only rye makes a somewhat spongy 

 bread, but of a dark color. 



Make up a large tablespoonful of wheat flour into a 

 soft dough, then put it in a linen or muslin bag or 

 folded handkerchief and knead it with your fingers in 

 a pan of water. The water will soon become milky 

 from starch that passes through the cloth. You must 

 keep on kneading until fresh water placed in the bowl 

 does not become milky. There then remains inside 

 the bag a gray, tough mass, which sticks to the fingers 



T 273 



