208 POMOLOGY 



clean tillage. The same rule to some extent applies to clover. 

 In the former case, miless receiving an abmidance of water, 

 often not the case, and care such as renovation and cultiva- 

 tion in its somewhat unnatural environment, this shade 

 crop does not make its best growth, and becomes soddy, a 

 condition not only inimical to its own welfare, but to that of 

 the trees as well. On the other hand, when organic matter 

 such as clover or alfalfa is turned under frequently, say once 

 in every three or four years, and followed by clean tillage, 

 disintegration of organic matter and bacterial action are 

 greatly accelerated, inducing great vigor of tree, especially 

 in ' off ' years when the crop is light." It is, therefore, recog- 

 nized that on the soils in question the nitrate was applied 

 as a special measure and gave excellent results, but that such 

 a treatment would probably not have been necessary had 

 a better system of soil management been followed. It should 

 also be stated in this connection that alfalfa may remain 

 in the orchard for a period of years when properly handled 

 without injury to the trees. 



The data in Tal)le LXVI give a summary of this work. 



178. West Virginia experiment.^ — The experiments con- 

 ducted in the Ohio Valley on impoverished soils, which 

 were under cultivation, corroborates the results secured in 

 southern Ohio. Nitrogen proved to be of first importance 

 in obtaining a vigorous growth of trees and maximum yield 

 of fruit. When phosphorus was used in connection with 

 nitrogen, the results were somewhat greater than was se- 

 cured from the latter alone, but the chief value of the phos- 

 phorus seems to have been in promoting a greater growth 

 of cover-crops and sod coverings. Potash apparently gave 

 no response in these orchards. 



lAlderman, W. H., and H. L. Crane. W. Va. Agr. Exp. Sta. Bull. 174. 

 1920. 



