46 BEGINNERS' GUIDE TO FRUIT GROWING 



(5) The cover crop may add nitrogen to the soil. 

 Such leguminous crops as peas, beans, cowpeas, soy- 

 beans, vetch, alfalfa, and clover collect nitrogen 

 from the air. This nitrogen finally becomes avail- 

 able for the use of the trees when the cover crop is 

 plowed under and rotted. Inasmuch as nitrogen is 

 the most expensive of the fertilizing elements when 

 bought in the market, this economy may prove to be 

 of considerable financial weight. 



The choice of a cover crop depends upon many 

 local conditions. The leguminous crops will be given 

 preference wherever possible on account of their 

 ability to supply some nitrogen. There are many 

 circumstances, however, which lead to the selection 

 of other kinds of cover crops. It is useless to sow 

 clover or alfalfa, for instance, on certain soils on 

 which they will not succeed. It is necessary in 

 order to get a good stand of clover or of alfalfa or 

 of any other leguminous crop that the soil shall 

 be sweet and that it shall be properly inoculated 

 with the bacteria with which these particular crops 

 are associated. In many cases it is worth while to 

 supply the land with lime when cover crops are to 

 be grown. In some cases an inoculation with bac- 

 teria will be found worth while. In a good many 

 cases, however, the fruit grower will have recourse 

 to other crops, especially buckwheat, which do not 

 require such special preparations. Buckwheat is, 

 in fact, one of the best of all cover crops in the 

 northeastern states, and for several reasons. It may 

 be successfully grown at a late period, seed can 

 easily be had at a reasonable price, it makes a good 

 stand and a heavy crop, it leaves the soil in excellent 

 physical condition, and it adds a large amount of 

 humus to the soil. 



