14 ORCHARD GREEN-MANURE CROPS IN CALIFORNTA. 
INOCULATION. 
The question is often asked whether it is not advisable to inoculate 
seed to be sown on land that has not previously grown 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- 
Fig. 2.—Experimental plats of horse beans at Chico, 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 
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