THE LEGUMES. 91 



The acreage in the United States is rapidly increasing. It 

 is being used in this country as a livestock food and as a soil 

 renovator. It has proven to be an excellent crop in a four or 

 five course rotation. A good course established by the Ohio Ex- 

 periment Station is a four-year rotation of corn, soy beans, wheat, 

 clover. 



Soy beans are an excellent crop after which to sow or seed 

 wheat, because plowing is unnecessary if the ground has been 



I ; IG. 2. Field of Soy Beans raised by Johnson Bros., Stryker, O. 



kept clean. Disking the soy bean stubble for wheat may be 

 sufficient. 



Soy beans are. a poor-land crop. They do fairly welt on a 

 wet soil, and yet they can resist much dry weather. 



As a soil builder compared with clover, the soy bean when 

 plowed under for green manuring yields the same amount of 

 nitrogen as plowing under an equal yield of green clover. 



According to experiment station reports, for every ton of 

 air-dried clover removed from a field there remains about twenty 



