2t 



utilizing some method of management specially adapted to the pre- 

 vailing conditions in each case, which will reduce the number of the 

 depredator- or otherwise prevent losses. 



SOME PRACTICAL RESULTS. 



A few example- may be given of the practical application of a 

 knowledge of some of the principal facts in the life history, as follow-: 



The recent determination that the tanbark-destroying insects do not 

 attack the stored bark until it is two or three years old suggested a 

 simple method of preventing losses. 



The determination that the spruce-destroying beetle attacks only 

 the larger trees, and that the beetles could be attracted to trees 

 hack-girdled during the proper period in June, suggested important 

 method- of forest management and lumbering operations, which will 

 contribute to the elimination of trouble from this pest 



Girdling and timber-cutting experiments have demonstrated the 

 possibility of preventing losses from the ravages of insects and wood- 

 destroying' fungi by girdling and cutting timber when the phvsiolog- 

 ical condition.^ are such as to render the bark and wood unattractive 

 to the depredators or unfavorable for their destructive work. 



A knowledge of the habits and characteristic work of bark-infesting 

 inserts in living, dying, and dead trees furnished conclusive evidence 

 that a large amount of healthy, uninfected, living timber had been 

 cut in the Black Hills forest reserve, where it was intended that none 

 but trees infested by the pine-destroying beetle or those killed by it 

 or other causes should be cut. It was also demonstrated that a knowl- 

 edge of the principal facts relating to the primary and secondary insect 

 enemies of the pine of this region would facilitate the drawing up of 

 timber-cutting contracts which would avoid much future trouble and 

 litigation relating to the interpretation of references to insect and 

 insect-killed timber. 



Facts determined relating to the habit of the pine-destroying beetle 

 of the Black Hill- and the relation of other insects and fungi to the 

 trees injured and killed by it suggested method- of future management 

 which would prevent the lo<s of much timber, and contribute to a 

 better public appreciation of the importance of Government forest 



- rves and the adoption of scientific fore-try. 



The facts which have been recently determined from special investi- 

 gations of the troubles caused by the destructive pine bark-beetle, the 

 chestnut timber worm, the oak timber worm, the giant root-borer, and 

 a number of other principal enemies of Eastern forest trees have made 

 available a fund of information which it i- believed can be used to 

 special advantage in formulating future plan- for the management oi 

 Eastern forest reserves, systematic forestry work, conservative lum- 

 bering, etc. 



