LEGUMINOUS FORAGE CROPS 



197 



229. Value. The value of alfalfa where it can be success- 

 fully grown consists in the large yield of palatable hay con- 

 taining a large percentage of protein. Thus the following table 

 based on the Twelfth Census and American analyses and diges- 

 tion experiments shows the importance of alfalfa: 



Comparison of Hays Grown in the United States in 1899 



It will be seen that in 1899 there was produced in the United 

 States about the same quantity of alfalfa hay as of red clover 

 hay off of about one-half the area; that the yield of digestible 

 nutrients was from two to two and a half times that of red 

 clover, while the digestible protein an acre in alfalfa was three 

 to four times that of red clover and about ten times that of 

 the cultivated grasses on the basis of the composition and diges- 

 tibility of timothy hay. 



Since alfalfa is a perennial, it reduces the labor of caring 

 for a given area of land to the minimum. It is not as well 

 adapted to short rotations as clovers, since the cost of securing 

 a seeding is greater, both because of the greater cost of the seed 

 and, in case no nurse crop is raised, because of the loss of a 

 crop. It requires what is recognized to be a fertile soil for 

 staple crops and cannot, therefore, be used alone in improving 

 worn-out soils. When grown on good soils with plenty of 

 plant food added, its large, deep-growing roots, rich in nitrogen 

 and minerals, leave the soil in an improved condition. 



1 Assumed for the purposes of comparison to be timoth}. 



