364 



ELEMENTARY STUDIES IN BOTANY 



FIG. 42. Red clover. 



appearance, with its three 

 leaflets (each usually with 

 a pale spot on the upper 

 surface) and head of rose- 

 purple flowers, should be 

 familiar to every one 

 (Fig. 42) . It is extremely 

 valuable for the many 

 purposes it serves, such 

 as hay, green fodder, pas- 

 turage, green manuring, 

 but its chief value is in 

 enriching the soil, as de- 

 scribed above. It is used 

 also as a " cover-crop" 

 in orchards, which means 



that it can cover the soil in such a way as to hold the moist- 

 ure, at the same time enriching the soil. Later it is " ploughed 

 under/' and it contributes still more 

 to the soil. 



Red clover can grow in a variety 

 of soils and climates, but at present 

 its most extensive agricultural use is 

 in the northern states. 



71. Alfalfa. This forage plant 

 (called also lucerne), a native of 

 western Asia, and long cultivated in 

 Europe, has become extensively cul- 

 tivated in the western states (Fig. 

 43). It was introduced into Cali- 

 fornia about sixty years ago, and its 

 cultivation has extended rapidly over 

 the arid regions of the Pacific and FIQ 43 . _ Alfalfai showing the 



Rocky Mountain States, where it is ^ general habit, a single flower, 



, , and the curiously coiled pod. 



grown more extensively than any After in. of British Flora. 



