418 FORAGE PLANTS AND THEIR CULTURE 



rather slowly the first season, but by fall have reached a 

 height of 3 to 4 feet, and a few of the plants will bloom, at 

 least in the South. By this time the root is large and fleshy 

 and may extend to a depth of 6 feet. The second season's 

 growth begins quite early, two weeks before that of alfalfa, 

 which at first it closely resembles. The stems reach a 

 height of 6 to 12 feet, and bear numerous white, sweet- 

 scented flowers in narrow, erect racemes. The mature pods 

 are reticulated and each bears a single seed. About the 

 time the pods are well formed, the leaves begin to drop off. 



Every part of the plant contains a bitter-tasting sub- 

 stance called cumarin, but which has a sweet, vanilla-like 

 odor. The young shoots contain but little cumarin, and 

 so are quite readily eaten by sheep and cattle, but the older 

 stems and leaves are decidedly better. About the time 

 sweet clover comes into bloom the stems rapidly become 

 woody. After fruiting the plants die. 



Individual plants vary in their content of cumarin 

 as well as in other characteristics, and some attempts 

 have been made to improve the plant by selection, and 

 particularly to secure a non-bitter variety. 



500. Adaptations. So far as climate is concerned, 

 sweet clover is adapted to southern Canada and practi- 

 cally the whole of the United States, thriving equally well 

 in semi-arid and in humid regions. 



Its soil relations are likewise very wide, as sweet clover 

 will grow in practically all types from cemented clays and 

 gravels to poor sand. It thrives best, however, on soils 

 containing an abundance of lime. Sweet clover, on 

 account of its deep root system, is able to withstand 

 drought nearly as well as alfalfa. On the other hand, it 

 can endure wet or poorly drained soils better than either 

 red clover or alfalfa. 



