DENVER – Spruce beetle infestation may not be the wildfire culprit that experts have led Southwest Colorado to believe, according to a new study.
Researchers at the University of Colorado Boulder, with funding from the National Science Foundation, found that infestations may not be to blame for increased severity of wildfires.
The findings were published recently in the journal Ecological Applications.
“Our study is unique because we were actually out in the forest peeling bark off of the burned trees, looking for evidence of the beetle,” said Robert Andrus, a graduate researcher in the Department of Geography at CU-Boulder and lead author of the new study. “We were interested in the ecological effects of the interaction between these two disturbances and determining whether more trees were killed by fire in areas of higher beetle infestation.”
The study does not question the widespread damage caused by the native insect.
Spruce bark beetles have affected roughly 500,000 acres of Engelmann spruce and subalpine fir forests across Colorado.
The beetles infested more than 87,000 new acres in Colorado just last year. With several large wildfires occurring across the state over the past decade, some fire officials opined that the beetle’s destructive spread may be a contributing factor.
But researchers – through direct field measurements – found that higher levels of infestation did not lead to more severe fires. They examined five subalpine fire zones in the San Juan Mountains of Southwest Colorado.
Factors such as topography and weather conditions play a larger role in determining the severity of Colorado’s subalpine wildfires, according to the study.
Researchers hope the findings guide state land managers and policymakers, who must decide how best to devote resources for fire suppression and spruce beetle-containment efforts.