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CALIFORNIA FRUITS: HOW TO GROW THEM 



fruits, containing, in each case, skin, pulp and seeds, are almost 

 entirely from California-grown specimens, and are supposed to 

 represent an average composition of the fruits named. 



Quantities of soil ingredients withdrawn by various fruits 

 Compiled from analyses by G. E. Colby, University of California 



flncluding hulls. 



*Estimated. 



FIRST AID TO THE INJURED SOIL 



Based upon the clear characteristics of California soils as 

 already indicated in the chapter on that subject, Dr. Hilgard advises 

 that any large-scale fertilization should begin with phosphates and 

 nitrogen, and, should this not prove fully satisfactory, then with 

 potash also, this being the order in which these substances are 

 likely to become deficient in most of our soils under cultivation. 

 In the course of time potash fertilization will become widely 

 necessary in this State; in fact some California soils are naturally 

 deficient in potash. 



AVAILABLE SUPPLIES OF PHOSPHATES 



Phosphatic manures which are clearly promotive of freer fruit- 

 ing of trees and vines, are now being supplied to fruit growers by 

 importers and manufacturers located in various California cities, 

 and results attained by their use are such as to warrant contin- 

 uance. They are bone and rock phosphates, which are transformed 

 into superphosphates, and, with nitrogenous matter added, serve 

 as good applications both for growth and fruiting. 



