MAKING THE SOIL PRODUCE CROPS* 



secured from the county agricultural agent and 

 the state college of agriculture in the county 

 or state of residence. 



Legumes as Soil Improvers. A means of soil 

 improvement that is well understood by progres- 

 sive farmers is the use of legumes to improve 

 the soil. The legumes include a large family of 

 plants of which the bean, the pea and the 

 clovers are outstanding examples. Such plants 

 have on their roots nodules which house nitrogen- 

 gathering bacteria. These bacteria absorb nitro- 

 gen from the air in the soil and, in the ordinary 

 process of growth, death and decay, make this 

 nitrogen available to the host plants, leaving a 

 residue in the soil for the roots of plants that 

 are to follow. Thus this group of plants, known 

 as legumes, have been used for generations as a 

 method of increasing the nitrogen content of 

 soils. Nitrogen, incidentally, is the most costly 

 element to buy in commercial fertilizers. The 

 soil-improving benefits of legumes may be 

 secured by growing them either for harvest as a 

 source of animal food or for plowing under as a 

 means of utilizing them entirely for the develop- 

 ment of soil fertility. 



In reading of the studies of soil fertility that 

 were made by George Washington at Mount 

 Vernon, we learn of the improvement that he 

 made in the relatively poor soils of that area by 



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