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to public interests. The introduction of forestry methods offers 

 opportunities for the adoption of method- 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 depredation-, which will lead to 

 the discovery of improved method- of control. 



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



The fruits of forest trees are injured by the adult- 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 larvae, by the larvae of moths, 

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

 many tree- are infested by larva? 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 it- way out and enters the ground, where 

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

 in time to deposit its Qgg> 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 lo>s of the commercial product of chestnuts, 

 hazelnuts, hickory nut-, etc. 



The seedling in the forest or in the nursery row i- attacked and 

 injured by many kind- of insects. The root- are eaten by the larvae 

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

 is attacked by wood and bark-boring beetle- and errubs. The foliage 

 i- devoured by caterpillar-, larvae of sawflies, and grasshoppers, or 

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

 twig- are injured by twig girdlers, twig miner-, scale insects, and 

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

 stunted or deformed. 



The young tree i- 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 vi the growing tree, are 

 those made in the root- and base of the stem bv the great root borer, 

 and in the wood of the main stem by the carpenter worm- and other 

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

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

 upon the vitality of the tree- infested by them, they cause a great loss 



