Reducing Bark Beetle Damage in eastern Oregon and Washington. When 

 sufficient susceptible host material is available, bark beetle populations can become 

 primary pests, capable of killing otherwise healthy host trees. Outbreaks subside 

 when suitable host material is depleted. We recommend the following actions to 

 minimize bark beetle damage: 



• Keep trees well-spaced and, therefore, vigorous; thinning changes stand 

 structure, disrupts beetle movement, and increases vigor tn residual trees. 



• Thin or clearcut lodgepole pine stands approaching 60 to 80 years of age 

 or 8 to 10 inches in diameter A long-term strategy for reducing damage 

 from mountain pine beetle in lodgepole pine is to maintain a mosaic of age 

 classes, preventing the whole landscape from being covered with uniform, 

 highly susceptible stands at the same time. 



• Remove or destroy trees that currently contain bark beetles before the 

 spring after the initial attack. Trees that have been killed by bark beetles 

 generally do not perpetuate risk of additional insect or disease damage to 

 the stand after the first year. 



Kri^-aTiE';?-- -; 





»V5?%. i'.Ui'^. ■ 



: i 'i-^f. /■• ^c'*/^.' *.">-■! r ■■ 



Quaking aspen needs fire to successfully regenerate from the roots of burned, killed trees. 



The Future— 8 1 



