' 



pine has "been advocated, which consists of peeling the trunk 

 without "burning, on the theory that the larvae will die from 

 exposure. 



If these beetles at the time of control opera- 

 tions were always in the larval stage, this would probably 

 work. Unfortunately, many of the broods are mature. This 

 method cannot be used in District 5 for the following reasons: 



1. Mature beetles are found at all seasons. 



2. Wherever broods are mature the beetles will not die 

 from exposure. 



3. The slash and bark constitutes a fire menace. leav- 

 ing this material on the ground is contrary to Forest Service 

 protective policy. 



4. The unburned linbs breed Ips confusus, killing tops 

 of mature trees and young growth, besides a host of secondary 

 insects which kill limbs and twigs of otherwise healthy trees. 



Therefore the same method will be followed in 

 sugar pine as in yellow pine infestation. 



Jeffrey Pine:- This species of tree must be treated the same 

 as sugar pine as the habits of the attacking species are the 

 same as the mountain pine beetle (Dendroctomis monticolae). 



Lodgepole Pine:- On account of the extremely thin bark and 

 the comparatively small size of this tree, all trees which 



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