156 MASSACHUSETTS HORTICULTURAL SOCIETY. 



in both cases they were large and for the most part healthy, 

 even when the experiment was concluded, which was not caused 

 by the normal dying of the trees, but by the fact that the 

 larger number of them were partially or wholly destroyed b}' a 

 severe windstorm. 



In the third place it is interesting to observe — and it is a point 

 of great importance — the effect of an abundance of food in over- 

 coming unfavorable weather or seasonal conditions. The year 1889 

 was extremely unfavorable, and the crop throughout the State was 

 small. In this experiment the unmanured plot yielded at the rate 

 of 10.9 baskets per acre, while the manured and fertilized plots 

 both showed a yield exceeding 150 baskets per acre. The manure 

 strengthened and stimulated the trees and enabled them success- 

 fully to resist such conditions as were fatal to the crop on the 

 unmanured land. 



This point is one that is seldom considered in calculating the 

 advantages to be derived from proper manuring, though it is of 

 extreme value, since the expenses of cultivation, trimming, and 

 interest on investment are quite as great in one case as in the 

 other. 



Another experiment bearing upon this point, recentlv reported 

 by the Cornell Experiment Station,' is also very instructive as 

 indicating the need of manures for fruit trees, not only in refer- 

 ence to the amount removed, but also in reference to the propor- 

 tions of the essential constituents required. 



This study shows that the plant food contained in 20 crops of 

 apples, of 15 bushels per tree and 35 trees per acre, and in the 

 leaves for the same period, amounts in round numbers to 1,337 

 pounds of nitrogen, 310 pounds of phosphoric acid, and 1,895 

 pounds of potash. These amounts of plant food are compared 

 with the amounts that would be removed by 20 years continuous 

 cropping with wheat, assuming an average yield of 15 bushels 

 of wheat per acre, and 7 pounds of straw to 3 bushels of grain, 

 viz. : 660 pounds of nitrogen, 211 pounds of phosphoric acid, 

 and 324 pounds of potash. By this comparison it is shown that 

 the 20 crops of apples remove more than twice as much nitrogen, 

 half as much again of phosphoric acid, and nearly three times as 

 much potash as the 20 crops of wheat. 



I Bulletin No. 103, " Soil Depletion in respect to the Care of Fruit Trees." 



