Swarms of tiny but ravenous beetles are destroying the white bark pine forests of the American West. For example, at Yellowstone National Park, the dead trees are so numerous that many visitors assume forest fires are to blame.

Prolonged frigid winter temperatures used to kill most of the pine bark beetles each year, but as the climate has warmed, more are surviving, multiplying, and chowing down on white bark pines.

It’s especially troubling because the white bark pine is essential to western ecology. The trees provide shade that protects mountain snow pack, a vital source of water in the dry months. They also support local wildlife:

Hansen: “It produces nutritious seeds that are an important food supply for many wildlife species, particularly the grizzly bear, which has been on the endangered species list. So both the hydrologic function and providing food for wildlife results in it being considered a crucial species.”

That’s Andrew Hansen, an ecologist at Montana State University. He says that tree planting, pesticides, and prescribed burns could help — but given the immense scale of the landscape and the problem, it’s not yet clear what can be done to defeat this tiny, but deadly foe.

Reporting credit: ChavoBart Digital Media.
Photo: White bark pine. Copyright protected.

More Resources
Yellowstone’s Iconic High Mountain Pines Dying by Beetle’s Mouth
Why Bark Beetles are Chewing Through U.S. Forests

Diana Madson

Diana Madson has been a regular contributor with Yale Climate Connections since April 2014. She enjoys exploring U.S.-based stories about unexpected and innovative solutions to climate change. In addition...