62 FARM CROPS 



field known to contain the desired bacteria to the 

 field where a crop is to be planted ; by soaking seed 

 in water in which soil from a field where the legume 

 has been successfully grown has been stored ; by 

 means of pure cultures and of specific organisms 

 suited to the legume. 



If soil be used it should be taken from some field 

 that is free of undesirable weeds. In getting the 

 soil it is best to go down where the roots grow; 

 somewhere between 2 and 6 inches from the sur- 

 face. This can be scattered directly over a field 

 or it may be mixed with the seed. Anywhere from 

 200 to 500 pounds to the acre will do. If the field 

 be in good condition, a small quantity will leaven 

 the entire mass. On the other hand, if the soil is 

 bad physically, a larger quantity may be better. 

 In any case get this material well distributed. 



The pure cultures have been worked out success- 

 fully and are now available. In selecting legumes 

 the nature of the soil should be considered. Sandy 

 soils are not attractive to clover. Cowpeas and soy 

 beans will grow in these sandy soils very satisfac- 

 torily. Give the sandy soils over to these crops 

 and save the clover for the more loamy areas. So, 

 too, if you want a permanent legume, let clover or 

 alfalfa be selected. In inoculating the land you 

 can always be sure that inoculation will be desir- 

 able if a small amount of humus is in the soil, if 

 the previously grown legumes lack nodules or if the 

 legume is used for the first time. Inoculation will 

 help when crops grow poorly although some nodules 

 are present. Inoculation is never needed when 

 there is already an abundance of nodules to be 

 found on the plants, or when the soil is already 

 supplied abundantly with nitrogen. 



