INOCULATION AND NITROGEN. 



Many once deep, dark mysteries are now cleared 

 up so that we smile at what once made men despair. 

 Alfalfa growing was once as deep a mystery as any 

 one could name. Sown in Colorado, Utah or Cali- 

 fornia alfalfa thrived from the start almost. Sown 

 in Ohio, Illinois, Kentucky or New York it often 

 failed. When it lived it was for some months or a 

 year or more a feeble, unhappy, sickly plant. After a 

 time perhaps it recovered and made wonderful 

 growth. 



Why This Difference? Why should it behave so 

 differently in different regions! Of course there 

 are several answers to this query. One is that some 

 soils are filled with lime and phosphorus, are dry 

 and filled with air. Alfalfa loves such soils. But 

 the other and more hidden and mysterious reason 

 is that of the nitrifying bacteria that help alfalfa 

 grow. These bacteria are naturally present in some 

 soils. They live on more species of legumes than 

 alfalfa alone. Burr clover (Medicago arabica or 

 Medicago denticulata) carries the same inoculation, 

 uses the same bacteria. So does sweet clover or 

 melilotus. Doubtless there are other wild legumes 

 growing in western arid soils that use the same bac- 

 teria. On the other hand, in eastern soils these bac- 

 teria were absent almost altogether. 



One of the best illustrations of the lack of inoculat- 



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