134 THE FORAGE AND FIBER CROPS IN AMERICA 



matter by reason of furnishing a base for the nitrous and nitric 

 acids formed, thus preventing the soil from becoming too acid 

 for the proper growth of the nitrifying organisms. The Cornell 

 Station found that not only was the size of the alfalfa plants 

 greatly increased where lime was added, but that the water 

 soluble nitrates were also greatly increased. 



Assuming that an increase in water soluble nitrogen is the 

 cause of the increase in the growth of alfalfa which is highly 

 probable, although not yet, perhaps, fully demonstrated the 

 observations above reported may be taken as indicating that 

 lime does assist in nitrification; or, since it has been demon- 

 strated that legumes excrete organic nitrogen into the soil, it 

 may be assumed that the lime furnishes the proper conditions for 

 the vigorous development of the tubercle-bacteria, and thus 

 the increase in the water soluble nitrogen is a result and not 

 the cause of the increased growth of alfalfa. Whichever may 

 be the fact, the lime asists the legume in some manner to get in 

 a comparatively short time an abundant supply of nitrogen. 



142. Value. Leguminous plants are of vast importance to 

 agriculture and hence to mankind. The different ways in which 

 they are valuable, especially the leguminous forage crops, may 

 be enumerated as follows: 



i. They help to balance the food ration of man and of do- 

 mestic animals. The great bulk of agricultural productions, 

 either in grain or roughage, is from plants belonging to the 

 grass family. The latter produce an abundance of starch and 

 other heat-forming substances, but are relatively deficient in 

 protein or muscle-forming foods. The leguminous crops produce 

 in the whole plant, as well as in the seed, a large percentage of 

 protein; hence they tend to correct, when used, the otherwise 

 one-sided ration. It is desirable to feed growing cattle clover, 

 alfalfa, or cowpea hay with the grain or stover of maize, for 

 the same reasons that human beings eat meat with potatoes. 

 Too much clover hay or too much meat would be undesirable. 



