TWENTY-FIRST ANNUAL MEETING. 107 



dressed with manure (one-tenth of a cord per tree) and the 

 same number with a complete fertilizer (5 pounds 10 ounces 

 per tree, or at the rate of 800 pounds per acre). The fertilizer 

 contained about 2 1/2 per cent of nitrogen, 10 per cent of 

 phosphoric acid and two per cent of potash. The experiment 

 showed that unfertilized trees made less growth than fertil- 

 ized trees, and the untilled portion less growtli than the tilled. 



On this land fertilizers were absolutely essential for 

 growth. 



The yields show great differences in individual trees un- 

 der the same treatment. Thus, in the four years for which 

 yields are given, single cultivated trees yielded from 4.7 to 

 20.1 bushels and the range of the mulched trees 2.5 to 23.8 

 bushels. The Tolmans, in the four years for which yields are 

 given, certainly yielded more per tree when mulched than 

 when cultivated, 166.4 bushels against 125.7 bushels. 



Stable manure gave higher yields than commercial fer- 

 tilizers, but not enough to meet the extra expense. No doubt 

 a considerable part of its effect was due to humus, which 

 could be more cheaply supplied in straw or hay, or in tilled 

 orchards by cover crops. 



Munson states, regarding an experiment with potash 

 salts in a Baldwin orchard about fifteen years old, continuing 

 ten years, that "in behavior of trees and gross character of 

 fruit no specific effect of any particular potash salt can be 

 observed." 



Now let us notice a ten-year experiment in fertilizing 

 a peach orchard in New Jersey^-. Without going much into 

 details, the experiment consisted in putting the three fer- 

 tilizer ingredients each by itself and in various combinations 

 yearly on plots of peach trees, and also testing plaster, yard 

 manure alone and with lime. 



The soil was a decomposed trap of average fertility and 

 seven crops were taken from this orchard before it was par- 

 tially destroyed by a wind storm. 



Every single application — excepting nitrate by itself — 



" New Jersey Station Report 1894, p. 125. 



