EXPERIMENT STATION BULLETINS. 239 



orchard every season, so that the ground has received good cultivation. 

 The manuring has consisted of an occasional application of composted 

 barnyard manure. This treatment has produced a healthy, vigorous 

 growth of trees and productiveness in fruit. The trees, which have been 

 remarkably free from diseases, bore their first fruit in 1890, and the 

 increase in quantity has been rapid, nearly all the trees bearing a large 

 crop last season. 



PKOPAGATION AND CULTIVATION. 



In propagation, the common stocks, Marianna and myrobalan are largely 

 used. The various varieties work well upon Primus Americana and other 

 native species, though the Chickasaws are said to be undesirable 

 because of their habit of sprouting and sending out suckers. Primus 

 Americana stocks are especially suitable for northern climates, because of 

 their hardiness. In the south the peach is largely used. 



Methods of planting and cultivation need not vary from those employed 

 with the common plums, except that, as many of the varieties of native 

 plum are not fertile, owing to the impotency of the pollen upon flowers 

 of the same variety, the prospective grower must bear in mind that, with 

 native plums in particular, he must practice mixed planting in order to 

 secure their fertilization. Some of the best kinds, including Wild Goose 

 and Miner, are worthless unless so planted. It is a matter of some diffi- 

 culty and considerable importance, to determine what varieties should be 

 planted near each other, in order to have the best mutual efPect as poUen- 

 izers. No definite rules for planting can be given without further exper- 

 imentation, and about all that can be said is that trees of different varieties 

 blooming at the same time should be planted near each other. They can 

 be so planted that a tree of a very polleniferous variety will fertilize sev- 

 eral barren trees. Some growers maintain that the mutual fertilizing 

 trees should be planted very close, eight or ten feet apart, but experience 

 here does not lead us to think close planting is at all necessary. Prof. 

 Bailey says that it is a "common opinion among plum-growers that the 

 European plums, peaches, and even the cherry will fertilize the Wild Goose 

 plum" and a case cited seemed to lend color to the view, but the writer 

 knows of three Wild Goose plum trees that stood in the midst of an 

 orchard of several varieties of common plum and a row of cherry trees 

 bordered the plum orchard, but not a plum did the Wild Goose trees bear, 

 and the trees were finally cut down by the owner. This shows at least 

 that considerable care must be observed in planting trees to fertilize those 

 that are not self-fertile. 



SOILS AND LOCATIONS FOE NATIVE PLUMS. 



Michigan has considerable territory that is admirably adapted to 

 growing these plums. Undoubtedly the country adjoining the great lakes, 

 especially that northward, is capable of greatest development for this 

 industry, as it is favored by soil, climate, and immunity from insects and 

 diseases. As a class, the native plums are not particular and will thrive on 

 various soils, although extremes in sand, clay, or muck must be avoided. In 

 an ideal soil, the trees should make a hard, strong growth, the wood should 

 mature early and well, the trees should bear young, and the fruit should be 

 well-flavored and highly colored. 



