SHADE TREES. 



163 



reverse effect. Continual pruning of the lower branches induces the 

 tree to grow taller than it otherwise would, and in some locations is 

 advantageous to the tree. Topping is destructive to the formation of 

 typical crow7is in such trees as the elm, hornbeam, etc., whereas in other 

 trees, like the Carolina poplar, topping or pollarding has a tendency to 

 thicken them up and make them more desirable shade trees. The con- 

 figuration of the crowns of maple trees is modified to some extent by 

 topping them when they are yoilng. This modification is manifested by 



Fi(i. -24. — Too common method of pruning limbs, resulting in the disfiguration of the tree : 

 (a) tree before pruning; (ft) limb cut too close, resulting in the peeling of the bark; 

 (r) unsightly wound caused by this method of pruning. 



the more vertical growth of the branches, thus producing a more narrow 

 crown. 



The cutting back of old trees is usually disappointing. It is often a 

 question as to whether this is worth while, although if not too far gone, 

 old trees may be restored to a more or less vigorous condition b}^ judicious 

 pruning, tillage and feeding. When elm branches a foot, or more in 

 diameter are topped, notliing but a bushy growth results. By removing 

 all but a single sprout, thus diverting the plastic materials, much better 

 gi'owth may be obtained, and replacing of the sacrificed member may be 

 more readily obtained. 



