43 



Even a glance at these tables can leave no doubt as to the posi- 

 tive and profound effect of proper fertilization on the yield of apples. 

 It will be noted that the checks run fairly uniform, averaging a 

 little over 190 bushels per acre annually. Lime applications (at the 

 annual rate of 1,000 pound per acre") have given almost exactly 

 the same returns as the average check. The phosphate and potash 

 combination has affected yield in this case rather decidedly, having 

 raised it by 123 bushels per acre. This may be partly due to a 

 slight superiority in location, as indicated by the fact that its ad- 

 jacent check is the highest in yield and is within 86 bushels of the 

 phosphate-potash treatment. While this increase in yield is fairly 

 satisfactory, there is nothing in the growth or appearance of the 

 trees of plot 5 that would lead one to believe that their treatment 

 is appreciably superior to that of the checks. In other words, the 

 trees of plot 5 still look starved and indicate that there is something 

 else lacking, although it will be noted that this is the fertilization 

 ordinarily recommended for orchards. 



This lack is very decidedly met by the manure treatment of 

 plot 8. In this plot, the trees are making a luxuriant growth, both 

 in wood and foliage, and the yields have been increased by 390 

 bushels per acre annually, — a very satisfactory exchange for 12 

 tons of stable manure. Even this increase in yield, however, is 

 considerably less than those obtained on the plots receiving a nitro- 

 gen-carrying fertilizer. Under the latter treatment on three plots, 

 the average annual yield has been increased from 191 bushels on the 

 checks to 649 bushels on the fertilized plots, or an annual inerease 

 of 457 bushels of apples per acre. This resulted from fertilizer 

 applications that actually cost less than $17, and the essentials of 

 which can be bought at retail for about $10 per acre. During the 

 past year, — the fourth year of the experiment, — as shown in Table 

 II, the yield on plots 2 and 3, compared with that of their adjacent 

 checks, was at the rate of 17 to i, the yield on the checks being at 

 the rate of 54 bushels per acre, while that on the intervening nitro- 

 ^^en plots was 922 bushels. vSurely it is not necessary to further 

 defend the thesis that proper fertilization may very profoundly af- 

 fect the yield of apples. 



There is no reasonable possibility of these results being due to 

 any other agent than the fertilizers. The trees are all of the same 

 variety and same age. They receive the same spraying, pruning, soil 

 handling and other care. The soil is practically level and very uni- 

 form. The treatments are abundantly checked. In fruit, foliage, 

 growth and general health of trees, the benefits stop abruptly where 

 the fertilizers stop, and similar results are being obtained by the 

 owner in other parts of the orchard, on the same and other varieties, 

 with the combinations of fertilizers found effective in the experi- 

 ment. 



In regard to the relative values of the different fertilizer ele- 

 ments, it will be seen in Table II, that nitrogen is evidently the first 

 limiter. Thus, the phosphate and potash combination in plot 5 has 

 given an increase of 123 bushels per acre, while by the addition of 

 nitrogen to this combination, in the adjacent plot 6, we get an in- 

 crease of 486 bushels. In other words, the addition of nitrogen to 



