10. To maintain equal yields, Stayman and Baldwin must make longer branch growth than York.
In addition to these conclusions I will say that any grower who will keep his orchard soil in a state of fertility (by use of manure, proper farm crop fertilizers—nitrate, phosphate or potash alone or in combination with each other—liming and, if necessary, drainage) which will permit growing clovers, alfalfa, soy beans, cow peas, vetch, or any of the legumes, and who really does grow them as covers in his grove or orchard, turning them back into the soil with a minimum period of spring cultivation—just enough to prepare a seed bed—will never need to worry about his soil fertility or water holding capacity.
You note that I say a minimum of cultivation. We taught twenty years ago that cultivation should continue during June, July, and August. We now feel that this teaching was wrong. We can see no benefit from this long summer cultivation but do see some harm. Cultivation during the hot weather of June, July, and August will only aid in burning out the organic matter in the soil, just the very thing we plant a cover for. Many of the covers such as alfalfa, sweet clover and non-legume grasses can be harrowed very heavily in early spring after the frost is out of the ground, thus checking their growth for several weeks, and it is in early spring before the first flowers open, and while open, that the tree needs its nitrogen to aid in the set of fruit, and season's tree growth; the checking of the cover's growth in early spring gives the tree the chance to get its food.
Dr. Zimmerman: I am very grateful for the address of Prof. Fagan.
Dr. Smith: I want to express my appreciation of Prof. Fagan's paper. I want to call to the attention of this convention of people that this young man has actually admitted his hard headedness, that he has been willing to let a tree compel him to change his thinking.