New York Agricultural Experiment Station. 935 



almost as great as on the fruit. The trees in sod gained 2.4 inches 

 in tree diameter, taking the average of the measurements, while 

 those under tillage gained an inch and a half more than this, or 

 3.9 inches. This difference extended in a similar ratio to gain in 

 height and spread of branches; and the foliage of the tilled trees was 

 so much more abundant, and of such dark, rich, green color, that 

 the line between the two plats could be recognized more than half 

 a mile away. 



Closer view showed more plainly the sparseness of foliage, irregu- 

 larity of branches, presence of dead branches and lack of plump, 

 healthy, bright-colored new wood on the trees grown in sod. The 

 trees under tillage, on the other hand, were very uniform in develop- 

 ment, with new growth and fruit well and evenly distributed, and 

 notable for their vigor and health. 



At the close of the first five years one quarter 

 Change of of the orchard was changed from sod to tillage 

 conditions. and another quarter from tillage to sod. In each 

 case the effect of the change was almost instan- 

 taneous. Before midsummer the trees released from the influence 

 of the sod showed plainly the benefit of the added moisture and 

 available plant food furnished them by tillage. Both trees and 

 foliage improved notably, and the apples on them grew as large 

 as any in the orchard. The number setting was, however, influenced 

 by the previous poor conditions so that the first year's crop was 

 below normal; but the average for the entire five years was as great 

 as that of the trees continuously under tillage. The change for 

 the worse was quite as remarkable and as immediate in the section 

 of the orchard turned from tillage to sod; for the average yield 

 per tree on this section during the first year was less than three- 

 quarters of a barrel, while even the trees continuously in sod yielded 

 twice this amount. 



The use of nitrate of soda on the sod helped matters somewhat, 

 and was a paying investment, yet for the whole five years the trees 

 in sod thus fertilized yielded less than half as much as the tilled 

 trees without any fertilizer. 



Since the trees under tillage have borne heavy 



Does tillage crops annually for ten years, without any addition 



exhaust to the soil except the seed of the cover crops used, 



the soil? it might be supposed that the soil would show 



the draft. Careful analyses made at the close 



of the test prove that this is not the case. The mineral elements 



of fertility are practically alike throughout the plats, and the nitrogen 



and humus are much greater on the tilled plats. Though analyses 



were not made at the start it is not probable that material differences 



then existed, for the soil is apparently quite uniform, and previous 



treatment had been the same for years. It is fair to conclude that 



the tillage and cover-crop treatment conserves nitrogen and humus 



