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POPULAR FRUIT GROWING. 



is, those under three years. Plums that have made a strong 

 growth may be set at one year old. Most planters prefer them 

 at this age as they are cheaper and easier to plant out than 

 older trees. Plums are generally planted from 16 to 20 feet 

 apart each way and for some dwarf varieties the smaller dis- 

 tance may be sufficient, but for the stronger growing kinds twen- 

 ty feet is little enough between them. As a rule a better plan 

 than planting equi-distant apart each way is to plant the trees 



Fig. 84. Old plum tree pruned in order to renew the top. 



16 to 20 feet apart in rows forty or fifty feet apart and grow 

 some other crop between. 



Mixing Varieties. There is some uncertainty as to the 

 flowers of the plum. Some varieties are generally, if not al- 

 ways, self-fertile, while others are commonly, if not always self- 

 sterile. These qualities seem to vary more or less, according 

 to location and soil. Much disappointment has arisen from the 



