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to public interests. The introduction of forestry 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 discover}' of improved methods of control. 



THE KINDS AXJJ CHAKACTER OF THE WORK OF INSECT ENEMIES OF THE FOREST. 



The fruits of forest trees are injured l)v the adults and larvae of 

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

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

 injured or destroyed by beetles and their larvie. l)y the larvte of moths, 

 and ])}' gall-making insects. Nuts of all kinds and the hard fruit of 

 many trees are infested b}" larvte 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 fully grown, bores its way 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 by the larvae 

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

 is attacked l)y wood and bark-boring beetles and grubs. The foliage 

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

 injured l)y plant-lice, scale insects, leaf-hoppers, and leaf-bugs. The 

 twigs are injured by twig girdlers, twig miners, scale insects, and 

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

 stunted or deformed. 



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

 by one ov 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 l)ase 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 capalile of working in the wood of living healthy 

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

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



