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DETAILED ACCOUNT OF THE CHIEF INJURIES. 



INJURY TO BULL PINE. 



The bull pine, or western yellow pine, Finns ponder osa Laws., occurs in 

 British Columbia only in the southern part of the Interior. It is specially 

 subject to attack by destructive Bark-beetles, Ambrosia-beetles, the larger 

 wood-borers, and a variety of other injurious forms. Its thick sap-wood is 

 rapidly attacked and destroyed by boring beetles and stained by bluing fungi; 

 so that the timber of beetle-killed trees should be utilized at once. 



Throughout its range in British Columbia, the bull pine is subject to attack 

 by three destructive species of Bark-beetles, and a number of lesser importance. 

 The Western Pine Bark-beetle, Dendroctonus brevicomis Lee., is one of the two 

 most injurious; the Western White Pine, or Mountain Pine Bark-beetle, D. 

 monticolcB Hopk., is as serious an enemy to the bull pine in British Columbia 

 as it is to the western white pine, or mountain pine, from which it derives its 

 name; and the Red Turpentine Bark-beetle, D. valens Lee., works in the inner 

 bark about the base of green pines attacked by the two more destructive species 

 just mentioned. Dying trees are also found in which this last species seems 

 the chief cause of the injury. 



Serious injury by these beetles, as evidenced by isolated trees and smaller 

 or larger patches of dying and dead trees, is to be noticed in many places; but 

 the most important and extensive outbreak known to us is that about Princeton, 

 in the southwestern portion of the Bull Pine area in British Columbia. 



BARK-BEETLE INJURY ABOUT PRINCETON. 



The trouble there is noticeable from the clumps of recently dead trees, 

 11 red-tops," which are now becoming numerous throughout the valleys and 

 upon the mountain-sides. When they were examined this summer, these 

 clumps of red-tops contained from five or six to about thirty trees; but will now 

 be considerably larger. The injurious beetles had then largely left the dead 

 trees, and were to be found in immense numbers cutting their tunnels and 

 depositing eggs in the inner bark of the trunks of green healthy trees surrounding 

 the clumps of red-tops. 



The boring of the beetles and their larvae through the inner bark cuts off 

 the sap-flow and seriously weakens or, more usually, rapidly kills the trees 

 attacked. Some trees survive attack for two or more seasons, particularly 

 when only part of the tree is at first infested; but in most cases the infested 

 trees are killed in one year. From 1,500 to 2,000 pairs of beetles were cutting 

 tunnels and depositing eggs in the lower fifty feet of many of the infested trunks 

 examined there this summer. 



Hundreds of trees have been killed by the beetles since the outbreak com- 

 menced about three years ago, and a large number are now infested with the 

 adults and larva?. Throughout the whole area affected, the number of killed 

 and dying trees must be very large. The trouble may be noticed from Vernon 

 through to Nicola, a distance of 250 miles. It appears to be widespread through- 

 out most of the Bull Pine area; but a few localities are more seriously affected. 

 The valleys of the Similkameen and Tulameen, in particular, are threatened 

 with serious loss. 



