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a large amount of nitrogen. It will have the advantage of growing 

 down deeper in the sub-soil than will vetch. Cow peas or soy- 

 beans might be used to advantage. I should prefer soy beans for 

 this section of the country ; they are more hardy, richer in nitrogen, 

 and are not subject to blight to the same extent as cow peas. Cow 

 peas will not require inoculation to the same extent but they will 

 do much better in soil that is inoculated, than will soy beans. These 

 can be used to advantage wherever conditions would permit. 



In order to be able to utilize the cover crop to best advantage 

 we must see that they make their growth. To make this point clear 

 let me tell you of a personal experience of mine. I happened to be 

 down in Monmouth County, N. J., in the potato section of that 

 county. One of the potato growers showed me a field of crimson 

 clover that was sown after the potatoes had been removed, on the 

 26th day of August. I was there on the loth or 12th day of Novem- 

 ber, and there was a mat of crimson clover on the soil five or six 

 inches high. The farmer said to me, "I am not at all concerned 

 about winter killing. I have all the nitrogen and all the humus I 

 need for next year, and if it is killed it matters little to me." Yet 

 under the same conditions, crimson clover sown at the end of 

 August might have made a growth of an inch or two. Why was 

 there, in this case, so much growth? Evidently that potato grower 

 had been using large quantities of fertilizer. He had a good soil 

 and that crimson clover made more growth in three or four weeks 

 than it would have made in another soil in two months. It is not 

 a practice in this country to fertilize the cover crop. We expect 

 the cover crop to shift for itself. 



In Germany they recognize that they can profitably stimulate 

 the growth of the cover crop. If we are to utilize a cover crop 

 particularly its vegetable matter in the fall or early spring, as the 

 case may be, we have to see that the cover crop finds the best condi- 

 tions for its growth, and these conditions are particularly important 

 to provide for when we are growing legumes. Legumes require 

 a large amount of lime. The amount of lime might be enough for 

 the apple trees themselves, but not enough for the cover crop. You 

 might have enough phosphoric acid for the slow growing trees 

 but not enough for the quick growing ones. So that in the prac- 

 tical utilization of cover crops you must make proper provision for 

 the presence of lime, and for the proper inoculation of the land. 

 These are the more important points in the use of cover crops and 

 because of the great length at which I have discussed these points, 

 I do not feel that it would be proper for me to discuss the matter 

 any longer, except in so far as you may wish me to answer specific 

 questions. 



C. J. Tyson. Do you think it practical for us to try to save seed 

 of winter vetch? 



Dr. Lipman. Yes, if you could grow winter vetch with rye, or 

 preferably winter wheat. Rye matures a little early for vetch, I 



