FOOD FOR PLANTS 113 



corn growing. That it is not generally done is no 

 argument against the value of such cultivation 

 methods. 



How It Was Done at Corona, California. , 



The rows were trenched eight inches deep, just 

 outside the drip of the trees, and the fertilizers spread 

 in the trench opposite the whole width of each tree. 

 This was done on two sides of each row in the same 

 direction, then covered by the plow. This, the only 

 plowing, was done on March 7, 1918. The applica- 

 tion of fertilizers in trenches is found to give the best 

 results in the orange groves of this section. 



Six after-cultivations to a depth of five or six inches 

 were given. These six cultivations were made during 

 the fore part of each of the months of March, April, 

 May, June, July and August. The March cultivation 

 consisted of a thorough disking. The other five 

 cultivations were made with the ordinary orchard 

 cultivator. 



The above trench fertilizing was done parallel with 

 irrigation furrows up one side and down the other, 

 nothing being applied on the other two sides. This 

 has given good results and the above method is rec- 

 ommended to California citrus fruit growers. 



Citrus Growing in California. 



The one-tenth of an acre plot of orange trees at 

 Corona fertilized with Nitrate of Soda and acid phos- 

 phate at the rate of 320 pounds of each per acre 



