SOME USEFUL PLANTS AND PLANT PRODUCTS 317 



recently has been extensively 

 cultivated in the western 

 United States ; its cultiva- 

 tion is being extended east- 

 ward. The cow pea, which 

 is closely related to the com- 

 mon bean, is grown most 

 extensively in the southern 

 United States. The soy 

 bean, a native of China and 

 Japan, is also being increas- 

 ingly grown in the United 

 States as a forage plant. The 

 hyacinth bean, a native of 

 India, is recommended as a 

 forage plant and has been 

 cultivated for this purpose to 



FIG. 175. An alfalfa plant. 



some extent ; but its chief use thus far, especially in tropical 

 and subtropical countries, has been as food for man. The 



common pea is also largely 

 grown in some parts of the 

 United States as a forage 

 crop. 



Various seeds, especially 

 those rich in oil, supply 

 valuable foods for animals. 

 Thus, cotton seeds are used 

 as food for cattle, and cot- 

 tonseed meal is made from 

 what remains of the kernels 

 after the oil has been pressed 

 out. Oil cake is similarly 

 made from the embryos of 

 corn grains from which the 

 FIG. 176. The soy bean. oil has been extracted ; En- 



