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The central fact to be noted in this connection is that 

 certain of our trees are less subject to insect injury than 

 others, and that it is possible by selecting judiciously to 

 have, much of the time, trees with clean whole leaves 

 without resorting to the use of insecticides and fungi- 

 cides. 



Trees Most Subject to Insect Injury. 



As to trees most subject to injury we may mention for 

 this locality the poplars, box-elder, and black locust, all 

 of which are very badly denuded of their leaves at times- 

 by caterpillars. The box-elder while a rapid grower, is 

 not as valuable for shade as are many other trees, and 

 can perhaps be spared. Some of the poplars are very 

 handsome, especially when young, and something should 

 be done to protect them. The black locust, with its 

 fragrant blossoms, is so pleasantly associated with spring, 

 that it seems ungracious to say anything against it. Yet 

 the plain truth is that it is not remarkable either for 

 beauty or shade, and its leaves are attacked by a small 

 army of insects that give it a draggled and unpleasant 

 appearance in the latter part of summer. Its trunk too 

 is mined by several destructive borers. If ash, elm, or 

 hard maple had been planted in place of most of the 

 black locusts in the State the appearance of our country 

 homes and roads would be greatly improved. 



Methods of Treating Shade Trees. 



For all insects that gnaw the leaves it is possible to ap- 

 ply mixtures which will serve to defend trees very ef- 

 fectively from injury. The chief difficulty comes from 

 the labor required and the cost of apparatus. If trees 

 threatened with injury from tent-caterpillars, fall web- 

 worms, walnut-worms, elm leaf-beetles, or any one of the 

 score of leaf-eating pests known to us, are thoroughly 



