The Cherry. 87 



105. Soil and planting:. The best soil for the plum is a 

 moderatelj-heavy clay loam, though some varieties succeed 

 admirably on rather light soils. A suitable distance for 

 planting the trees is 20 to 25 feet apart, depending some- 

 what upon the vigor of the variety. 



The varieties of the American species of the plum are 

 largely impotent with their own pollen — a fact that greatly 

 emphasizes the importance of mingling the varieties in 

 planting (14). 



B— THE CHERRY 



106. The cultivated cherries of the United States and 

 Canada include the following species: 



(a) Prunus avium, the bird cherr}^ of Europe, the sweet 

 cherry of North America, or the English cherry, to 

 which the classes known as Mazzards, Hearts, Bigarreaus 

 and Dukes belong, is characterized by the usually tall, up- 

 right growth and pyramidal form of the tree. This has 

 large, vigorous and straight young branches, with soft, 

 coarsely- or doubly-toothed, pointed leaves, which are usu- 

 ally pubescent beneath. The flowers are developed at the 

 same time with the leaves, and the usually sweet or bitter 

 fruit is round-ovoid or somewhat heart-shaped and of vari- 

 ous colors. The cultural range of this species is rather 

 limited and it is not hardy in northern United States nor 

 in Canada except in favored districts. The fruit is used 

 for dessert, canning and pickling. 



(b) Prunus cerasus, the red, sour, or pie cherry, which 

 is a smaller tree than the above and includes the Ama- 

 relle and Morello classes, has small, irregular and thickly- 

 growing branches, with obovate lance-ovate, serrate leaves, 

 rather large flowers on shortish pedicels that somewhat 



