THE FRUIT INDUSTRY IN CALIFORNIA. 



215 



zation and scientific study of the laws of heredity and variation 

 applied to plants ? " The answer is, " Yes ; there is no assignable 

 limit to the capacity of our cultivated fruits, and of fruits still 

 wild, to improve and develop new characteristics." 



The second great task relates to the ceaseless struggle with the 

 lower forms of animal and vegetable life which prey upon useful 

 forms in immeasurable and innumerable hosts. Gophers and 

 jack-rabbits are now only pests of minor importance in thickly 

 settled orchard-districts, but the warfare of the horticulturist 



FcMiGATiuo Tent, llydrocyitnic-ucici gas process for aestroying scale. CJiiiio Valley. 



with fungoid diseases and parasitic insects long ago passed its 

 amusing stage. It is a serious business of importance to the 

 whole human race, because whatever threatens the food supply 

 threatens the life of man. The practical applications of skill 

 and capital in the field of preventive and remedial agencies have 

 been remarkable. Every successful Californian fruit-grower has 

 now learned that he must as regularly treat his trees for scale 

 and other inflictions as he must plow his land, thin the fruit, or 

 gather the crop. At the spraying season in the fruit districts 



