352 



FIELD CRVPS 



The sweet clover leaflets are arranged like those of alf a If a, and 

 the plants are quite similar till they begin to bloom. 



Alfalfa, Medicago sativa, differs from the other plants of 

 the genus which are found in America in that it is peren- 

 nial instead of an- 

 nual, and that the 

 flowers are usually 

 purple, while those 

 of the others, the 

 medics or the bur 

 clovers, are yellow. 

 The numerous 

 stems which are 

 produced arise from 

 a crown, growing 

 from 15 to 24 inches 

 long, and are erect 

 or spreading ac- 

 cording to their 

 length and the 

 thickness of the 

 stand. The long 

 taproot penetrates 

 to a great depth, 

 with many small 

 branches or feed- 

 ing roots. The 



Figure 120. — Alfalfa plant showing the manner in 

 which a large number of stems are produced from 

 one root or crown. 



leaflets vary great- 

 ly in size, but usually range from J/^ to 1 inch in length 

 and somewhat less in width. The flowers, which are slight- 

 ly larger than the individual flowers of red clover, are in 

 short racemes. • They are usually violet-purple in color, 

 though sometimes much lighter, inclining to a pale whitish 

 or yellowish purple. The pods are in two or three coils, 

 brown when ripe, and contain several seeds. The seeds are 



