KAMIAH More than 600 acres of forested state lands affected by the 2015 wildfires near Kamiah were recently treated to prevent infestations of bark beetles.
Idaho Department of Lands (IDL) and U.S. Forest Service forestry professionals stapled 7,300 bubble caps filled with a pheromone produced by Douglas-fir beetles to trees throughout and adjacent to burned areas to prevent mortality in healthy stands of trees.
According to an IDL release, the buildup of bark beetle populations in fire-injured trees and subsequent attack in adjacent areas is a concern for forest managers after wildfires because the insects can easily spread to adjacent healthy stands of trees.
The pheromone, called “MCH” is available commercially and acts as a signal to invading beetles that the targeted tree is fully occupied and resources are too limited to support more bark beetle colonies.
Incoming beetles picking up the scent then continue their search for an available tree within which to develop their brood. Continuous searching for an unprotected tree exhausts beetle food stores to the point of mortality, exposes them to predators, or redistributes them in the landscape, reducing the number of attacks from Douglas-fir beetles in protected trees.
Application of MCH must be completed before the beetles start flying in spring.
This year’s efforts are in addition to 450 acres that were treated in 2016. The efforts are supported in part by grant dollars from the U.S. Forest Service Western Bark Beetle Grant Program.
An additional 25-acre treatment area is scheduled for May near Riggins.