6 INSECT DAMAGE IN THE NATIONAL PARKS. 



THE DOUGLAS FIR BEETLE. 



The Douglas fir beetle attacks the Douglas fir, the big-cone spruce, 

 and the western larch. The beetles fly in April and May and enter 

 the living bark on healthy trees and on trees that have been injured 

 by fire and those that have been recently felled. In habits of attack 

 and general characteristics the Douglas fir beetle is similar to the 

 mountain pine beetle, except that the former begins to fly earlier 

 in the season and the foliage of the trees infested begins to die in 

 the fall. It is very destructive to the Douglas fir throughout the 

 Kocky Mountain region from British Columbia to Mexico, but is 

 much less so on the Pacific slope, especially toward the coast. It 

 can be controlled by felling the infested trees during the period 

 between the 1st of September and the 1st to middle of the following 

 April and removing the infested bark from the trunks without 

 burning. 



THE RED TURPENTINE BEETLE. 



The red turpentine beetle is the largest species of the genus Den- 

 droctonus. It begins to fly in April and is active until October and 

 Novenibor. It attacks the pine and rarely the spruce. As a rule it 

 confines its operation to the base or basal portion of the trunks. 

 ^Miile its normal habit is to breed in the bark of stumps and logs of 

 newly felled trees, it often infests the bark on healthy trees. It 

 rarel}' kills a tree, but is the cause of a large percentage of the basal 

 wounds known as "cat faces" and fire wounds, so commonly met 

 with in the pine. This is a far more difficult species to control than 

 the others because it bi'eeds in the stumps of felled trees and the base 

 of those killed by the other species or by fire. Valuable individual 

 trees can be protected b}' cutting the beetles out of the bark as soon as 

 their presence is indicated by masses of exuding resin mixed witli 

 reddish boring 'dust. 



Wherever there are continued lumbering operations the red turpen- 

 tine beetle confines its attack to the stumps, but in the national parks 

 and private grounds where a limited amount of timber is cut, or 

 where the ravages of the mountain pine and western pine beetles 

 have been controlled, it is likely to cause more or less extensive dam- 

 age to the living timber for a year or two after. 



In combating the other beetles in the national parks, care should 

 be taken to remove the bark from the stumps whenever they are 

 found to be infested with this pest. 



THE ENGEL.AIANN SPRVCE BEETLE. 



The Engelmann spruce beetle attacks the Engelmann spruce, blue 

 spruce, and any other species of spruce found within its range, but 



