EXPERIMENTS ON CULTURAL METHODS, COVER- 



CROPS, AND FERTILIZATION IN 



APPLE ORCHARDS. 



Dr. John P. Stewart, Experimental Pomologist, 

 State College, Pa. 



To develop and maintain an apple orchard in its highest 

 state of efficiency involves many decisions. Even among 

 the principal operations, there are generally at least two 

 available courses, between which it is often difficult to de- 

 cide. In such cases the ideal procedure whenever possible 

 is to ask the trees. With the individual orchardist, how- 

 ever, this is frequently out of the question, especially when 

 immediate action is required or when only a few trees of a 

 single variety are available. The comprehensive orchard 

 experiments, and the careful determination of the general 

 effects of the leading operations, should therefore be cared 

 for by the various state and national agencies already pro- 

 vided. The net results of such experiments then be- 

 come available to the grower as a basis for immediate 

 action, and the latter can be further adjusted to the exact 

 local needs by means of suitable tests wherever the opera- 

 tions are sufficiently extensive. 



Experiments of this general character have now been 

 in operation under the writer's direction, in the leading 

 orchard sections of Pennsylvania since 1907. Altogether 

 ihes€ experiments include ten different soil types and about 

 3700 trees, some 2200 of which are in various stages of bear- 

 ing. The latter have produced over 42,000 bushels of fruit 

 Tinder the various treatments during the last 6 years. The 

 wide extent of the work largely eliminates the variations of 

 individual trees and localities, and incidentally makes thia 

 much the largest and most comprehensive series of experi- 



