N I TRO- CULTURE 203 



Pot No. I. — Not inoculated. 



Pot No. 2. — Inoculated with bacteria obtained from 

 infected alfalfa soil. 



Pot No. 3. — Inoculated with bacteria obtained from 

 alfalfa root tubercles. 



Pot No. 4. — Inoculated with bacteria obtained from 

 infected Sweet clover soil. 



Pot No. 5. — Inoculated with bacteria obtained from 

 Sweet clover root tubercles. 



The results indicate that the same effect is produced 

 upon the growth of the alfalfa by the nitrogen-gathering 

 bacteria obtained from Sweet clover as by those from the 

 older alfalfa, and seem to prove that infected Sweet 

 clover soil can be used for the inoculation of alfalfa fields. 

 Investigations have shown that lOO pounds of thoroughly 

 infected soil to the acre is sufficient to produce a satisfac- 

 tory inoculation within one year from the time it is 

 applied. 



