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way, to increase his crop yields? It is for the farmer to decide 

 whether his soil is deficient in nitrogen or not. If the trees are mak- 

 ing all the growth he thinks they ought to make, then it would not 

 be wise for him to grow leguminous cover crops. He might better 

 depend on barley, oats, or winter wheat and not grow legumes. 

 There is danger of excessive wood growth. I remember an ex- 

 perience of ours in one of our experimental peach orchards at Vine- 

 land. This particular area of land of gravelly loam had been re- 

 duced to the point where it would not grow corn. It was soil that 

 would be regarded as exhausted. We planted our peach trees 

 there, and Prof. Blake, after watching them the first season said 

 "I do not believe I would care to have more wood growth than the 

 trees are making, and I should not care to apply any leguminous 

 cover crop." I told him that, looking at it from the standpoint of 

 the soil chemist, it was true perhaps, but it does not follow that 

 next 3^ear or the next after you will not want to grow a cover 

 crop. Now, we find that the trees that gave us the best returns 

 were those that had received applications of nitrate of soda. They 

 had too much nitrogen, or enough of it, earlier in their history. 

 So when it comes to the practical application of the teachings on 

 the value of cover crop, we must use our judgment in deciding 

 what is best to use; whether they will make enough wood growth 

 or not. 



But on the other hand, he would be quite safe in using more 

 legumes, and if he prefers his vegetable matter to die down and 

 leave the winter cover dead, he might use barley. If you prefer 

 something early in the Spring, he might use winter rye. If he 

 feels that the soil is deficient in nitrogen, he has a number of 

 legumes from which to choose. 



What legumes could the fruit growers of Adams County, Penn- 

 sylvania use with any dependence, for increasing the supply of 

 nitrogen as well as of vegetable matter in his soil? Winter vetch, 

 clover or alfalfa. Alfalfa in this connection may be new to you, 

 but I believe that with proper inoculation, alfalfa may be a very 

 good cover crop. And of course cow peas, and soy beans should 

 be included in the list. So we have not many legumes available 

 for our purpose. Of all those that I mentioned, perhaps alfalfa and 

 winter vetch are the most promising. For soils that are not well 

 drained or inoculated, winter vetch would be the most satisfactory 

 cover crop. Winter vetch has the advantage of being very resis- 

 tant. In Michigan peach orchards winter vetch is regarded as 

 the best cover crop. Winter vetch is hardy and does not depend on 

 inoculation as much as does alfalfa, and will add considerable 

 quantities of nitrogen and vegetable matter to the soil. It makes 

 a very good cover and under favorable conditions, will form a solid 

 mat. The amount of nitrogen added by winter vetch will range 

 from 50 to 100 pounds per acre. Alfalfa is a promising cover crop, 

 where the soil is deep and well drained, and properly inoculated, 

 it will make enough growth in the early fall and spring to furnish 



