14 



ORCHARD GREEN-MANURE CROPS IN CALIFORNIA. 



INOCULATION. 



The question is often asked whether it is not advisable to inoculate 

 seed to be sown on land that has not previously growTi that crop. In 

 California it has been found that the bacteria necessary to nodule 

 formation on the more common leguminous crops are present in most 

 soils. The first seeding may not, however, be as abundantly inocu- 

 lated as desired, and in some sections the bacteria essential to certain 

 crops seem to be entirely lacking in the soil. 



In northern California it has been observed that horse beans are 

 not inoculated the first year they are grown on soil that has not pre- 



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Fig. 2.— Experimental plats of horse beans at Chlco, Cal., showing the striking superiority of the noduled 



plants. 



viously grown this crop. (See fig. 2.) Thus, to obtain the best 

 results, it is necessary to inoculate the crop the first year. The dif- 

 ference between an inoculated and an uninoculated crop of horse 

 beans in the Sacramento Valley is very marked and is practically 

 the difference between success and failure. In southern California 

 this crop does not require artificial inoculation, the soil being inocu- 

 lated. 



In the inoculation of horse beans the surest results are obtained by 

 securing soil from an inoculated plat or field and mixing this with 

 the seed at the time of seeding. In this way but little soil will be 

 required to inoculate a large area, and practically no extra time or 



190 



