GOOD SOILS BACK OF GOOD CROPS 15 



the fertility of the land, and why the growth of 

 leguminous plants is always a cheaper process of 

 fertilizing than is the application of commercial 

 fertilizers. Wherever clover and alfalfa can be 

 successfully grown they are unquestionably the 

 best of all leguminous plants for fertilizing pur- 

 poses, but sometimes soils are too poor to grow 

 either successfully. On such soils cowpeas will 

 usually produce a large growth and succeed in fix- 

 ing considerable quantities of nitrogen. 



