THK PLUMS OF NEW YORK. 121 



to get into the dense, thomy heads; heading-in such varieties would make 

 their tops wholly impenetrable. 



In common with all tree-frtiits the best plum orchards are tilled. 

 Such tillage usually consists of plowing in the spring followed by frequent 

 cultivation tmtil the middle of August, at which time a cover-crop of 

 clover, oats or barley is sown. The pliim seems to require more water 

 than other tree-frtiits — it often thrives in comparatively moist land and 

 fails on sandy soils where the peach would grow luxuriantly. Culti- 

 vation to save moisture is very necessary for the plum in the experience 

 of New York growers. Grass and grain have proved ruinous in most 

 orchards where tried, though cultivated crops between young trees to 

 pay for keep until fruiting-time are very generally planted. The claim 

 is made by some, and with a show of reason, that there is less of the brown- 

 rot in tilled orchards than in neglected ones for the reason that the mummied 

 fruits which carry the fungus through the winter are buried by plowing 

 and with shallow cultivation, at least, do not come to light and life. 



Plum-growers very generally recognize the several distinct and valu- 

 able 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 sttfficient 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 appli- 

 cations 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 



