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to public interests. The introduction of forcstiv methods offers 

 opportunities for the adoption of methods of preventing much of the 

 losses which under previous conditions could not be avoided. It also 

 offers opportunities for extended research and experiments for the 

 determination of the more important facts relating to the habits and 

 life histories of the insects and their depredations, which will lead to 

 the discovery of improved methods of control. 



THE KINDS AND CHARACTER OF THE WORK OF IXSEtrT ENEMIES OF THE FOREST. 



The fruits of forest trees are injured by the adults and larvas of 

 species which feed upon the pulp, pod, or other covering, and thus 

 destroy the seed or prevent its normal dcxelopment. The seeds are 

 injured or destroyed by beetles and their lar\'a3, by the larvfc of moths, 

 and by gall-making insects. Nuts of all kinds and the hard fruit of 

 many ti'ees are infested by larvae from eggs deposited in the growing 

 fruit by small beetles. The entrance of the young larva through the 

 young, tender hull or outer shell heals over so that the ripe nut shows 

 no trace of it. The larva feeds on and destroys the germ and kernel 

 and, when fuUj^ grown, bores its wa}- out and enters the ground, where 

 it goes through the transformations and emerges as an adult next year 

 in time to deposit its eggs in the young nuts. Thus the seeds of some 

 trees may be so completely destroyed that few remain for reproduc- 

 tion. This may cause considerable expense and loss to the forester, 

 both in adding to the expense of collecting a sufficient quantity of 

 sound seeds and in causing an uneven stand in the nursery on account 

 of the damage to the stored and planted seeds. This class of injuries 

 also causes a serious loss of the commercial product of chestnuts, 

 hazelnuts, hickory nuts, etc. 



The seedling in the forest or in the nursery row is attacked and 

 injured by manj^ kinds of insects. The roots are eaten Ijy the larvse 

 of beetles and the sap sucked out or poisoned by root-lice. The stem 

 is attacked bj' wood and bark-boi"ing beetles and grubs. The foliage 

 is devoured by caterpillars, larvse of sawflies, and grasshoppers, or 

 injured by plant-lice, scale insects, leaf-hoppers, and leaf-bugs. The 

 twigs are injured b}' twig girdlers, twig miners, scale insects, and 

 plant-lice. As a result, the seedling maj' either be killed or become 

 stunted or deformed. 



The young tree is in a like manner attacked and injured or killed 

 by one or more enemies of the roots, stem, or top. The principal 

 injuries, however, which are characteristic of the growing tree, are 

 those made in the roots and base of the stem by the great root borer, 

 and in the wood of the main stem by the carpenter worms and other 

 borers, which are capable of working in the wood of living healthy 

 trees. While this class of enemies may have little or no direct effect 

 upon the vitality of the trees infested by them, the}' cause a great loss 



