Feb., 1926] PROGRESS OF AGRICULTURAL EXPERIMENTS 21 



would be profitable under New Hampshire conditions; but because the 

 weight of drops is included in this figure which represents total yield, 

 the packed fruit wovild be less 'than what we consider the minimum for 

 a good commercial orchard. The sod trees yielding less than 100 pounds 

 total fruit would not only pay no return on land and investment, but 

 would show a loss on operating expense of the orchard. In considering 

 these yields, however, it must be remembered that the average is reduced 

 bj' the two years near failure due to birds. 



Whereas, during the first. ten years of the experiment, fertilizers pro- 

 duced no appreciable increase in yield, it is evident that from the 10th 

 to the 17th year the fertilized trees have borne appreciably more fruit 

 than those cultivated only. The average increase for Plots 6, 7, 8 and 

 10, which receive complete fertilizer in addition to cultivation, is about 

 40 pounds of fruit per tree above the yield of trees cultivated only. The 

 increase in yield for Plot 9, which receives additional nitrogen with the 

 complete fertilizer, is approximately 90 pounds of fruit per tree. The 

 value of a bushel of A grade fruit under the market conditions prevailing 

 in New England for the past few years has been approximately eighty 

 cents on the tree. However, not all of this increased yield of fruit would 

 be of A grade or better, and consequently it wOuld probably be more 

 nearly correct to assume that the 40 pounds of fruit has been worth on 

 the tree before harvesting, approximately forty to forty-five cents. 

 The cost of a fertilizer under present market conditions is approximately 

 twenty-five cents per tree, so that during this period the increased yield 

 has been sufficient to pay at least the current cost of the fertilizer. The 

 comparison for Plot 9, which receives additional supplies of nitrogen, 

 is even more favorable if the value of the fruit is assumed to be ninety 

 cents and the cost of the fertilizer thirty-eight cents. 



It must be borne in mind, however, that the increased 3'ield during 

 this period is probably due to a considerable extent to larger size of trees 

 due to fertilizer applied during the first ten years of the experiment. The 

 total increase in production for the seventeen years would not be suffi- 

 cient to pay for the total fertilizer bill plus the compound interest for 

 the years in which no return was received. However, the inventory 

 value of the trees in the fertilized plots based on their present evident 

 ability to remain permanent fruit producers is much greater than the 

 present appraisal value of the trees in the plots which are not fertilized. 

 It is now an open question as to whether or not the trees in the fertilized 

 plots are not worth sufficientl}^ more than the other trees to pay for the 

 first ten years that the fertilizers were applied. If this is true the fertilizer 

 has been used at a profit. 



It should be noted that in this experiment there is no possibility of 

 comparing the effect of the different elements because in every case a 

 complete fertilizer is used. The only possibility to make such an obser- 

 vation is to compare Plot 8, which receives additional phosphorus, with 

 Plot 9, which receives additional nitrogen, and Plot 10, which receives 

 additional potash. Within the accuracy with which yield is measured, 

 there are no significant differences in jaeld between Plots 6, 7, 8 and 10, 

 which received normal amounts of fertilizer or increased* phosphate or 

 increased potash. However, in Plot 9, in which the amount of nitrogen 

 is increased, there is a very significant increase in the yield. It may also 

 be stated here that the present condition of the trees in Plot 9 is much the 



