LEGUMINOSiE 455 



yellow flowers. It blooms somewhat earlier than the white 

 sweet clover and is more commonly annual in its habit than 

 biennial. It is a native of Eurasia and, Uke the preceding 

 species, has become naturalized in this country, being widely 

 distributed as a ruderal throughout both the Northern and 

 Southern States. 



Environmental Relations. — The sweet clovers thrive in 

 both semi-arid and humid chmates, and upon all types of 

 soils — heavy and Hght, rich and poor, well-drained and illy- 

 drained. They are also drought-resistant. It is being intro- 

 duced where, for any reason, alfalfa and clover have failed. 



Uses of Sweet Clovers.^ — Like other legumes, sweet clover 

 supports nodules of bacteria on its roots. In fact, it is 

 nearly as valuable as alfalfa to plow under as a green manure 

 to renew the soil. It makes good hay when properly 

 handled, and for pasturage purposes it has considerable 

 value. As a forage crop, it can be utilized where alfalfa 

 or red clover cannot be grown successfully. The plant 

 becomes coarse and unpalatable soon after blooming, and 

 hence it must be cut before this stage. The plants possess 

 a bitter principle, cumarin, which may cause an animal to 

 reject them as food at first, but usually the animal becomes 

 accustomed to them. 



White sweet clover is much larger and more vigorous than 

 yellow, and consequently is the one recommended for 

 cultivation. 



SOJA (Soy Bean) 



Generic Description.- — The soy beans are prostrate or 

 erect herbs with pinnately three-, rarely five- or seven-, foliate 

 leaves. The flowers are in short axillary racemes, and are 

 purple or whitish. The pods are linear or falcate, and two- 

 valved. The seeds are globular and pea-like. 



