252 FIELD CROP PRODUCTION 



If a plant is carefully dug out and the roots examined, 

 the presence of the nodules will insure the presence of 

 the bacteria. 



The amount of soil to apply will depend upon the ease 

 of getting it. If the soil is close at hand, a liberal appli- 

 cation should be made, but if it is necessary to transport 

 it some distance, a smaller amount, carefully spread over 

 the field, will usually introduce a sufficient number of 

 bacteria to insure inoculation. From 200 to 800 pounds 

 per acre may be used, the amount depending upon the 

 ease of procuring it. The soil should be taken from the 

 first four or five inches of the surface soil, and spread over 

 the new field late in the afternoon, or on a cloudy day. 

 Direct sunlight is a strong bactericide, and if the soil is 

 spread over the field in direct sunlight, many of the bac- 

 teria may be killed. The soil should be harrowed 

 immediately after the application. The grower should 

 exercise care in getting the soil, as fungous and bacterial 

 diseases, or weed seeds, may be introduced at the same 

 time as the desirable bacteria. 



