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where soils of the right character are found. He would call particular 

 attention to the fact that the successful cultivation of alfalfa would 

 not only mean a valuable addition to our forage crops, but would 

 also mean soil improvement, for where alfalfa has been successfully 

 grown the soils are sure to be rendered more productive. This im- 

 provement in the case of alfalfa would be a consequence, first, of the 

 extensive subsoiling due to the deep penetration of the great tap 

 roots of the plant; and, second, to an accumulation of nitrogen in 

 roots and stubble, drawn in the first instance from the air. It will be 

 understood that when an alfalfa sod is plowed this nitrogen will be- 

 come available to succeeding crops. 



