134 The Principles of Fruit-growing 



than the wheat. No one would think for a moment of 

 trying to raise wheat, even on our best New York land, 

 for twenty consecutive years, even though the soil was 

 fitted in the best possible manner yearly." 



Apple-orchard experiments. 



Yet, as explicit and striking as are these calculations, 

 the results of experiments in the fertilizing of apple orch- 

 ards are very contradictory. 



This is perhaps to be expected. It probably represents 

 undetermined differences in the lands imder experiment. 

 Inasmuch as we do not possess sufficient knowledge to 

 enable us to harmonize the results, some of the most 

 prominent findings are given here for such guidance and 

 information as the reader may be able to secure from 

 them. Hedrick reports the conclusions of a fifteen-year 

 experiment on the fertilizing of apples by the New York 

 (Geneva) Experiment Station in part as follows (Bull. 

 No. 381) : 



"Current recommendations for fertilizers in orchards are unreliable 

 because there have been few investigations of the subject which have 

 furnished trustworthy information. Present practices are largely 

 based on the fertilization of field and garden crops, but the needs of 

 apples cannot be compared, in the least, with the needs of herba- 

 ceous crops because of the great difference in the habits of growth of 

 the two kinds of plants. Fertilizing apples is a difficult problem, too, 

 for, beside variability of plant and environment to contend with, as 

 with all plants, it is necessary to take thought of the tree and of the 

 crop of the future. 



"This experiment has to do with apples — ^not apples and grass. 

 Attention is called to this fact because most of the investigations 

 of fertilizers for apples have been carried on with trees in sod. In all 

 such experiments the interactions of soil, apples, grass and fertilizers 

 are so complicated that a crucial test is impossible. 



"The experiment under discussion was carried on in a station 



