Mountain pine beetles may be contributing to haze and air pollution in western forests, including the Black Hills, according to a recently released study.
Local Forest Service personnel say, however, that’s the least of their worries.
Beetle-infested trees may release up to 20 times more organic substances than non-infested trees, the study said. Trees release volatile organic compounds to fight the beetles that bore into the trees’ bark. The compounds produce haze that may harm human health, reduce visibility and affect climate, according to the study.
Though increased haze may obscure views of scenic Black Hills sites, what concerns local officials more is halting the spread of the beetles and preventing those green trees from turning to red forests.
“In the scheme of things, with the concern that we have, it’s a pretty small factor. The gigantic problem we’re dealing with is the dead trees and the spread every year. That’s the problem,” said Dave Mertz, natural resource staff officer for the Black Hills National Forest. “The biggest problem is the trees, the rapid spread.”
One infested tree can lead to eight to 10 other trees being infested the following year, which causes a problem that grows exponentially, Mertz said.
Other side effects of the beetle figure more importantly than haze, according to the forest official.
“There’s the social impact of having all these dead trees, there’s the economic impact of the visibility, and the value of all these dead trees that we’re losing from a timber standpoint. And there’s the fuels and wildfires,” Mertz said.
Mertz added that haze has many causes, some likely much more detrimental to health, such as coal-fired power plants.
Still, the study illuminates the fact that the effect of pine beetles is more than just a few dead trees and may be deeper than previously thought, according to the study's authors.
“These results highlight one of the many potential feedbacks due to aerosols, which continue to be the greatest challenge to improving predictive models for air equality, visibility and climate,” Alex Pszenny, program director for the National Science Foundation’s Division of Atmospheric and Geospace Sciences, said in a statement. The National Science Foundation funded the study.
The study compared the levels of volatile organic compounds in the air near healthy pine trees and infested pine trees.
Scientists Kara Huff Hartz of Southern Illinois University Carbondale and Gannet Hallar of the Desert Research Institute’s Storm Peak Laboratory in Steamboat Springs, Colo., spearheaded the study, which was published by the American Chemical Society in the journal Environmental Science and Technology.