Soy Beans as a Supplementary Silage Crop 



261 



and stalks of soy bean plants were made from inoculated and uninocu- 

 lated crops. It was found that inoculated soy beans produced nitrogen 

 valued at $2.34 more an acre than did the uninoculated soy beans.* 

 The Michigan Agricultural Experiment Station made similar trials, in 

 which it was found that inoculation increased the nitrogen in soy bean 

 plants almost 50 per cent.f 



The bacteria that cause tubercles to grow on other legumes, as alfalfa, 

 clover, and peas, do not produce tubercles on soy bean plants. Tubercle 



Fig. 54. — -Soy bean stems and roots showing the characteristic formation of tubercles due 



to seed inoculation 



bacteria adapted to the soy bean plant should be introduced in planting 

 a field that has never grown soy beans. This may be done by scattering 

 soil over it from a field that has grown inoculated soy beans, and har- 

 rowing it in before planting; or commercial cultures of soy bean bacteria 

 may be used with success to inoculate the seed before planting. 



There is some positive evidence that the growth of alfalfa and field 

 peas associated with other plants increases the nitrogen content of the 

 other plants, t In practice it has been noticed that the mixing of field 



♦Wisconsin Agricultural Experiment Station Report, 1907, p. 162. 

 tMichigan Agricultural Experiment Station Bulletin 224. 

 ^Cornell University Agricultural Experiment Station Bulletin 294. 



