Plum-growers very generally recognize the several distinct and valuable purposes which cover-crops serve in orchards. They protect the tree from root-killing, from cold, keep the soil from washing, add humus and, with legumes, nitrogen to the soil, modify the physical structure of the soil and hasten seasonal maturity of the tree. There is one other function which is not so often taken into account. Plum orchards in which cover-crops are regularly grown, even though the crop be not a legume, need less fertilizers than those in which no such crop is grown. There are several reasonable suppositions as to why there should be such an effect, but one not usually given sufficient consideration is that cover-crops make available much plant food in the soil. Each plant in the crop collects food from soil and air, most of it otherwise unavailable, and turns it over to the trees. A discussion of fertilizers naturally follows. Present practices in the use of fertilizers with the plum, as with other fruits, are very diverse. It is impossible to ascertain what considerations have governed the applications of fertilizers in the plum orchards of New York or what the results have been. Too often, it is to be feared, fertilizers have been used as “cure-alls” for any or all of the ills to which trees are heirs. Out of the mass of conflicting data as to the effects of fertilizers on plums, the most apparent fact is that much of the fertilizers for this fruit is wasted; this in face of the fact that plums want rich soils. But the plum crop is mostly water, the foliage remains on the ground, the trees grow several years before fruiting, their growing season is from early spring until late fall, the roots go deep and spread far, the trees transpire large amounts of water, hence may thrive on diluted solutions of plant food, and now and then there is an off year in bearing for the trees to recuperate. It does not follow from the above consideration that plums never need fertilizers, but it does seem plain that they need rather less than truck or farm crops and that applications of plant food must be made with exceedingly great care if fertilizing is to be done without waste. There is a growing disposition on the part of plum-growers to experiment very carefully and know that they are getting the worth of their money before using any considerable quantity of fertilizers for their trees.