PLUMS AND CHERRIES 177 



are "self-sterile." That term means that the 

 pollen from a given tree will not fertilize the 

 fruit on the same tree — or on other trees of that 

 variety. The same thing is true to a large 

 extent in the case of cherries and for that rea- 

 son plantings of either tree should include more 

 than one variety. Some sorts seem to be fertile 

 when planted alone. Others appear fertile in 

 one section and sterile in another so that it is 

 not possible to give a definite list of sterile and 

 fertile sorts and feel sure that such a list would 

 be accurate for all localities where the fruits 

 might be grown. It is far better to play safe 

 by planting a number of varieties, making a 

 shotgun prescription of it and being sure that 

 there will be a sufficient assortment of pollen 

 to insure fertility to all the varieties grown. 



I have mentioned that the Japanese varieties 

 of plums are largely grown on peach roots and 

 the foliage is almost as tender as that of the 

 peach. There is another similarity in that the 

 trees should be pruned in almost the same way 

 that peaches are. To start with, the trees are 

 cut back to a stub about eighteen inches high at 

 planting time. At the end of the first season 

 these stubs should have produced strong shoots 

 varying from a foot to three or four feet in 

 length. These shoots are again shortened in — 

 each one being treated exactly as was the young 

 tree in the first place. After that the annual 



