Hog Park Reservoir, Medicine Bow National Forest, Wyoming
Hog Park Reservoir in the Medicine Bow National Forest. The U.S. Forest Service’s annual aerial survey shows pine beetle activity has slowed.
(U.S. Forest Service – click to enlarge)
(U.S. Forest Service – click to enlarge)

Pine beetle kill slows in Wyoming forests

by Kelsey Dayton
— February 25, 2014
Kelsey Dayton
Kelsey Dayton

Results from the U.S. Forest Service’s recent aerial survey showing the slowing of the pine beetle epidemic in Wyoming isn’t necessarily good news. The slowdown is mostly attributable to the fact that many trees are already dead. “It’s not really a victory,” said Wyoming State Forester Bill Crapser.

The U.S. Forest Service and Wyoming State Forestry Division recently released results of the annual aerial forest health survey in Wyoming, showing the spread of mountain pine beetles in the past year. One key trend is the insect’s activity “has slowed dramatically” expanding by only 29,000 new acres, primarily in the southern Wind River Range on high elevation five-needle pine trees, such as whitebark and lodgepole pines.

The forest service began the aerial surveys in 1996 near the start of the mountain pine beetle epidemic, which has killed more than 3 million acres of trees in Wyoming so far. The information provides land managers current data to help guide management strategies and prioritize work on forests, said Bob Cain, regional entomologist with the U.S. Forest Service’s Rocky Mountain Region. “A lot of things are looking better because there are fewer hosts,” Cain said.

Pine beetles are native insects, and outbreaks are a natural part of the regeneration of the forest. The outbreak provides a chance for the forests to come back healthier. Many western forests are the same age due to logging when the West was settled, Cain said. As the forests regrow, patch cutting can help diversify the ages of trees in the forest making them less susceptible to pine beetle outbreaks in the future.

“Even though we’re losing old growth forests, it’s happened before,” he said.

The difference is, it hasn’t happened at this level, noted Crapser. The pine beetle epidemic began in Wyoming in the late 1990s and by the mid-2000s it had expanded across the state. The insects transformed the landscape by 2008 and made many realize the size of the epidemic was different than ever seen before, Crapser said.

Thirty years ago, Crapser heard professors say pine beetles never attack trees smaller than 7 inches in diameter. In some areas the beetles have been found in trees with diameters as small as 3.5 inches, he said.

The beetles also have moved into higher elevations. Historically whitebark pine trees weren’t threatened by beetles, but with drought and climate change the insects can survive at much higher elevations. Scientists have measured up to 90 percent mortality in lodgepole pines in some areas. “It will be a long time in those areas until you see solid lodgepole pine forests like we had,” said Crapser.

Unfortunately, cold snaps like the ones that hit the state this winter rarely kill the pine beetles anymore because they are so short. It takes weeks of continuous 20- to 25 below zero weather to kill pine beetles, which produce a type of antifreeze to protect them in the winter.

While the Medicine Bow, Bridger Teton and Shoshone National Forests were hit hard by the beetles, one area that escaped the devastation is the Big Horn National Forest. This year only 320 acres in the forest were infected by beetles. “They have gorgeous trees,” Cain said. Forest managers are trying to understand why the area has stayed healthy while they also use past experience to protect the forest if beetle activity begins to pick up in that area.

In the Black Hills, forest managers are suppressing pine beetles by thinning ponderosa pine, making the trees more vigorous. The strategy also spaces the trees farther apart thwarting the beetles from spreading tree-to-tree.

The dead forests pose new management challenges, changing the fire regime and wildlife patterns on forests, Crapser said. “We have to decide ‘What do we want our forests to look like 100 years from now and how do we get there?’” he said. Management tools include prescribed burns and salvage logging, he said. To help paint that 100 year vision, Wyoming Gov. Matt Mead created a task force to recommend ways to improve forest health across the state.

The U.S. Forest Service, according to a press release, has four 10-year contracts across the region to remove dead trees. In 2013, timber harvested from regional national forests totaled enough to construct 25,000 homes.

“Restoring forest health and resiliency is a top regional priority and is guiding the work on the forests,” Dan Jiron, regional forester for the Rocky Mountain region of the U.S. Forest Service, stated in the press release.

The future for Wyoming forests isn’t all bleak. Even in areas where many of the pine trees are dead, undergrowth plants are still thriving and some subalpine spruce is growing. “There is a lot of green still there,” Crapser said. “The forest isn’t destroyed. It’s still a forest. It’s just a different forest than we’ve ever seen.”

— “Peaks to Plains” is a blog focusing on Wyoming’s outdoors and communities. Kelsey Dayton is a freelancer and the editor of Outdoors Unlimited, the magazine of the Outdoor Writers Association of America. She has worked as a reporter for the Gillette News-Record, Jackson Hole News&Guide and the Casper Star Tribune. Contact Kelsey at kelsey.dayton@gmail.com. Follow her on twitter: @Kelsey_Dayton

REPUBLISH THIS POSTFor details on how you can republish this post or other WyoFile content for free, click here.

If you enjoyed this story and would like to see more quality Wyoming journalism, please consider supporting WyoFile: a non-partisan, non-profit news organization dedicated to in-depth reporting on Wyoming’s people, places and policy.

Kelsey Dayton is a freelancer and the editor of Outdoors Unlimited, the magazine of the Outdoor Writers Association of America. She has worked as a reporter for the Gillette News-Record, Jackson Hole News&Guide...

Join the Conversation


Want to join the discussion? Fantastic, here are the ground rules: * Provide your full name — no pseudonyms. WyoFile stands behind everything we publish and expects commenters to do the same. * No personal attacks, profanity, discriminatory language or threats. Keep it clean, civil and on topic. *WyoFile does not fact check every comment but, when noticed, submissions containing clear misinformation, demonstrably false statements of fact or links to sites trafficking in such will not be posted. *Individual commenters are limited to three comments per story, including replies.

Your email address will not be published. Required fields are marked *

  1. Thanks to the visionaries before us that came up with the idea of wilderness designation, we don’t have to watch “management” of forests in large areas (Washakie, N. Absaroka, Bridger, Fitzpatrick, Popo Agie, Teton) of the B-T and Shoshone National Forests . The Big Horn and Med Bow will be a different story ….

  2. Mr. Wuerthner knows his stuff. Kelsey…. Lodgepole pines are two-needle pines, Limber is the other 5-needle pine. White pine blister rust has also played a big role in the Whitebark die-off. Two summers ago I was in the Bighorns and noticed that there was very little die-off, it was very interesting. Keep up the good work.

  3. Unfortunately this article has the same “smart resource management” attitudes that has created most of our environmental problems.

    Pine beetles are not a problem as portrayed, but a natural consequence of specific conditions of forest age, working with climatic conditions. The forest is adapted to these kinds of events, indeed dependent upon them. Beetles are critical for creating dead wood. Dead wood is an essential element for forest biodiversity. For instance, one study has shown that 45% of all bird species depend on dead trees. And that is only the beginning of the list of plants and animals that find dead beetle killed trees useful at some point in their life cycle.

    Yet the entire “tone” of this article has the usual economic bias of foresters and the timber industry which tends to view anything but a fast growing trees as “bad”. In fact, a “healhty” forest is one with dead trees. There is growing ecological evidence that dead trees are more important to forest ecosystems than live trees. So the entire premise of this news piece that somehow wyoming forests have been “destroyed” “devastated” “ravaged” or whatever other negative adjective you want to you displays significant ecological ignorance.

    Furthermore while the current beetle kill is larger than what has been seen in the past 50-100 years, there is no good evidence that what we are seeing today is outside of the normal variability if you look back more than a hundred years.

    I.e. Just as you might wrongly conclude that the Yellowstone fires of 1988 were “abnormal” if you just viewed them through the past 50-100 years instead of the 500-1000 year lens needed to understand that big fires are “normal” in this ecosystem, but infrequent, separated by hundreds of years, the same is true for pine beetles outbreaks.

    Furthermore, quoting widely from a state forester is like talking to a Nuclear power plant engineer about the safety of nuclear energy, in other words, I have never met a forester who understood forest ecology. As a former forestry school graduate (who then took 30 ecology courses) I can attest that what you learn in forestry school is how to manipuate and cut down trees. You have to go outside of the “normal” forestry school requirements to get a more wholistic perspective of forests that goes beyond economic values.

    Next time I hope that a more balanced overview of the beetles is presented and to do that you have to talk to more than people whose job is to facilitate the logging our forests–i.e. you don’t talk to state foresters or forest Service silverculturalists if you want to get a clear idea about these issues.

    A much better source of information would come from geographers and botanists and others who don’t have a “dog in the fight” so to speak.

  4. I commend Bill Crasper for finally articulating publically an opinion I’ve held for some time now: beetle-affected forests are still forests! After working in the Black Hills and listening to the tourist and forest products industries there, one would think that MPB tree mortality was akin to complete nuclear destruction. This kind of thinking leads to the mentality that beetle-affected forests just need to be salvaged and left for dead. However, these millions of acres are indeed still a living, dynamic ecosystem-and still serve as critical resources, including watershed, wildlife, and plant habitat. Forests are messy places, they burn, they get overgrown, trees die; they are not always the human playland we think they should be. There have indeed been great human and ecological tolls taken by the MPB epidemic, but it is also a great opportunity to redeem ourselves and the poor management practices of (hopefully) the past.