SOYBEANS 



525 



pean grown plants dur- 

 ing the twenty years 

 after the crop had been 

 introduced. 



Smith and Robinson 

 at the Michigan Agri- 

 cultural Experiment 

 Station made observa- 

 tions on the influence 

 of nodules on the roots 

 upon the composition 

 of the soybean. The 

 conclusion of two years' 

 work was that the nod- 

 ules on the roots, in a 

 fairly fertile soil, may 

 not notably increase the 

 yield, but do increase 

 the relative and absolute 

 amounts of nitrogen in the plants. In the following table 

 is given the composition of the dry matter of leaves, stems 

 and roots of inoculated and not inoculated soybeans : 



FIG. 61. Roots of soybean, showing 

 nodules. 



