26 



and the bark removed before the broods of bark-beetles emerge, vast 

 numbers of these pests would be effectually destro} T ed. 



The prevention and intelligent control of forest fires is also believed, 

 as previously stated, to be a most important precaution against the 

 extension of insect depredations, as is also the prevention of insect 

 ravages, and the proper management of timber killed by them, a 

 necessary precaution against forest fires. 



The introduction of natural enemies of destructive insects as a means 

 of controlling them might prove effectual under certain favorable con- 

 ditions, but before this or any other method is recommended for the 

 prevention and control of forest pests, each separate trouble, and the 

 attendant physical and other conditions prevailing in the region or 

 forest in which it prevails, should be thoroughly studied. 



SUMMARY AND RECOMMENDATIONS. 



Before concluding this preliminary report it seems proper to call 

 attention to some of the insects and subjects relating to their destruc- 

 tive ravages which the results of my investigation suggest as the most 

 important for investigation. The insects mentioned in the following 

 list were found to be of special economic importance on account of 

 their destructive habits, and therefore demand primary consideration: 



Dendroctonits drevicomis Lee, a widely distributed and common 

 barkbeetle, destructive to the Western yellow pine and the sugar 

 pine; observed in California, Washington, Oregon, and Idaho. 



Dendroctonus n. sp., a common and destructive enemy of the white 

 pine and the sugar pine; observed in Oregon and Washington, and 

 reported from Montana and South Dakota. 



Dendroctorms similis Lee, a very common and widely distributed 

 enemy of the red fir and Western larch; observed in California, 

 Oregon, and Idaho. 



Scolytus prceceps Lee. and closely allied species, one or more of 

 which are very common, widely distributed, and destructive enemies 

 of the fir; observed in California, Oregon, and Idaho. 



Geometrid larvce, destructive to the foliage and causing the death of 

 vast quantities of Tideland spruce and hemlock in Clatsop and Tilla- 

 mook counties, Oreg. ; the result of its work observed. 



Melanophila drummondl Kirb} r , or a closely allied species, a common 

 and destructive enemy of the red fir, hemlock, and noble fir; larva? 

 and work observed in Oregon, Washington, and Idaho. 



JVeophasia mencqna F 'eld., the pine butterfly, a common and destruc- 

 tive enemy of the Western yellow pine in Idaho and eastern Washing- 

 ton; its destructive work observed. 



The first five insects named in this list are probably the five worst 

 insect enemies of the Western forest. The evidence found indicates 

 that they have caused the death of many million dollars' worth of the 



