8 N. H. AGR. EXPERIMENT STATION. [Bulletin 168 



' ' The experiments of this Station have shown that the fertility 

 of an orchard may be the most important check on its production. 

 Variations in fertilization alone have resulted in average differ- 

 ences ranging from 50 to 460 bushels per acre annually for the 

 past four or five years depending on the experiment. These 

 results were accompanied by similar differences in the growth 

 and general vigor of the trees. ' ' 



These experiments show beneficial effects from fertilizers both 

 on trees in sod and under cultivation. Manure is giving the best 

 results when the orchard is in sod and commercial fertilizers the 

 best results in cultivated orchards. This is the first one of the 

 experiments noted where a decidedly beneficial effect has been 

 secured by fertilizing an orchard which is receiving a good sys- 

 tem of orchard culture including a leguminous cover crop. We 

 wish to call special attention to this fact in view of the recom- 

 mendations given in this bulletin, viz., it may or may not pay to 

 fertilize a well-tilled orchard. 



SOME OHIO EXPERIMENTS. 



The Ohio Experiment Station has in progress a number of 

 experiments in orchard fertility in the southeastern portion of 

 the state where tlie soil is thin and the fertility low. The work 

 there is confined to orchards in sod and under the sod mulch 

 system. Remarkable results have been secured in their work and 

 the following extract from a letter by F. H. Ballon,* in charge of 

 the work, gives a summary of the work for the past five seasons : 

 "To sum up the results in increased fruit production from the 

 use of chemical fertilizers on the very thin orchard land in south- 

 eastern Ohio, taking into consideration all our different plots 

 at the various places covering 60 miles of country we have the 

 following : 



Average per acre, per year fertilized, 100 barrels. 



Average per acre, per year unfertilized, 44 barrels. 



Gain per acre, per year from fertilization, 56 barrels. 



Cost of gain per barrel per year, 17.8 cents. ' ' 



THE PROBLEM. 



The New Hampshire Experiment Station has had an apple 

 orchard under treatment for the past six years to study the 

 factors which infiuence the formation of fruit buds. A report 

 was issued on this work by Prof. B. S. Pickett, Bulletin 153. 

 But coincident with this study is a study of the effect of various 

 cultural treatments and commercial fertilizers on the growth of 

 the trees and yield of fruit. This state has a great number of 

 apple trees which have not received either cultural treatment or 



* Letter dated October 17, 1913. Newark, Ohio. 



