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Rocky Mountain National Park Crews Battling Bark Beetles With Insecticide


Stacks of dead conifers were hauled out of Rocky Mountain's Glacier Basin Campground last fall due to bark beetle attacks. NPS photo.

To what lengths should national parks go to combat climate change? Do such efforts run contrary to the National Park Service's mission, to let natural processes run their course? And in some cases, are those efforts akin to turning back a flood with a rake?

Those questions come to mind in the wake of ongoing efforts at Rocky Mountain National Park to save "high-value trees" from infestations of bark beetles. Some forest entomologists believe the massive infestations of bark beetles -- pine beetles, spruce beetles, etc -- in recent years are the result of a warming climate.

In Rocky Mountain, crews a few weeks ago began applying a Carbaryl-based insecticide to up to 5,000 high-value trees to try to thwart bark beetles.

Treatment will occur in the following developed areas of the park: Beaver Meadows Visitor Center & Headquarters area, Moraine Park Visitor Center and the William Allen White Cabin, Kawuneeche Visitor Center, Aspenglen, Moraine Park, Glacier Basin & Timber Creek Campgrounds, Bighorn Ranger Station, McGraw Ranch, Holzwarth Historic Site, and east and west side Park Service housing areas.

Last year, nearly 5,000 other trees were treated with Carbaryl and most of these trees were not attacked by bark beetles. To be effective, spraying must be done annually and applied directly to trunks. Broadcast spraying is not effective, according to Rocky Mountain officials. And since there can be adverse impacts with Carbaryl spraying, park staff are selective and limit use of this chemical.

For instance, spraying does not take place near water courses or wetlands. The total number of trees treated may be less than 5,000 trees depending on site conditions. The Longs Peak Campground will remain chemical free for this year.

Rocky Mountain is just one relatively small area where trees are dying from the beetle epidemic. Because the task is enormous, the park’s priorities for mitigation of the effects of beetles are focused on removing hazard trees and hazard fuels related to the protection of life and property.

For several years, the park has had a proactive bark beetle management program. This year the park will continue its mitigation efforts, including spraying, removal of hazard trees, prescribed burns, utilizing the air curtain burner and implementing temporary closures in a variety of park locations.

Beetle mitigation work continues at Glacier Basin Campground and Timber Creek Campground as well as specific backcountry campsites. Most trees in Timber Creek Campground have been killed by the mountain pine beetle epidemic. Clearing is taking place in both campgrounds. Glacier Basin Campground is expected to be open by Memorial Day with first-come, first-served sites. Timber Creek Campground is expected to open by mid-June.

For more information about Rocky Mountain National Park please contact the park’s information office at (970) 586-1206.


Oof, tough issue, and an example of how adults (as compared to knee-jerk, single-issue, pouty types) have to make decisions.

Do you spray pesticides in a National Park?
Do you let nature take its course in eradicating signature trees/forests?
Do you consider the bark beetle, an invasive species not native to this country, to be a natural phenomenon or not?
Do you only work to save areas in view of hte public and leave the rest of the park to to succumb? Or do you only spray where you can spray without costing millions and millions of dollars (air-drop pesticides in remote areas, anyone??)?

I can see this policy appeasing no one, but it certainly seems something needs to be done. I've seen the huge tracts in the Arizona forests that have been completely devastated by the bark beetle, and it's not pretty. Not pretty at all.


My travels through the National Park System:


You touch on some very difficult points that the NPS has to address. It must be interesting sitting in on their planning process. Should parks be managed for their aesthetics? After all, mountain pine beetles are natives and have been around about as long as lodgepole pines. So should you selectively manage for the lodgepoles, or also ride out the peaks and valleys of beetle infestations.

And, of course, there are many who hold the position that climate change is a natural phenomenon. If so, shouldn't the NPS simply ride out the side effects and explain the natural process to visitors?

And why treat areas that are highly visible or which enhance settings, such as around campgrounds, and not also address wilderness areas? Part of the sequence of beetle infestations are wildfires that often follow in their wake. If a fire starts in the backcountry, depending on how extensive the beetle kill is it could sweep right through any healthy trees left around campgrounds.

Difficult questions all.

Certainly the most visible areas should be treated.The National Parks,testament to natural forces that they are, are also an investment by the US people in a shared heritage.They are not the private playgrounds for environmentalists or gov. study groups.

I don't have personal knowledge of the current program at Rocky Mountain, but from experience with similar situations elsewhere, I strongly suspect one criteria for decisions on whether to treat a particular area involves safety.

Beetle-killed trees in areas such as campgrounds and parking areas become a safety hazard, so one of the questions is whether trees in those areas can be "protected" from beetles; if so, they won't have to be removed. When a forest insect outbreak is as extensive as the current one in the West, any kind of "treatment" program--or the lack of one-- is expensive and controversial.

The aesthetic issue is a difficult one, especially in mountainous areas where vistas can cover an enormous area. I was in the park last summer, and heard several comments from local residents lamenting the impact of the beetles on the scenery, not only in the park, but throughout the whole region.

Applying a chemical insecticide to control a natural occurring insect so as to maintain a scenic setting is potentially a slippery slope for park management. Chemicals rarely remained confined to a target specie or remain within a defined special management zone. They pass through the food chain becoming increasingly concentrated as they move from one specie to the next (as described in Silent Spring). My first reaction to the article was to wonder why hazard trees were not simply removed and the infestation cycle allowed to run its course. Once the chemical control strategy is employed it will likely establish a precedence of maintaining a functionally artificial setting for esthetic purposes rather than trying to be minimally intrusive. Ecosystems, by their nature, are dynamic. Trying to freeze one in place rarely succeeds and is ultimately counterproductive.

Is the bark beetle a "naturally occurring insect" in those parts, Ray? I thought they were "immigrants", i.e. non-native?

Ecosystems, by their nature, are dynamic. Trying to freeze one in place rarely succeeds and is ultimately counterproductive.

This is a brilliant statement, thanks! Plus you can use those changes to teach. In Shenandoah there used to be roadside signs pointing out the healing scars from an old, huge wildfire. Certain parks in the west include marking showing how fault lines have slipped or avalanches have changed the landslide.

Good reminder!


My travels through the National Park System:

Barky, pine beetles evolved alongside lodgepole pines. They are very native. I'm pretty sure the same can be said of spruce bark beetles.

Now, white pine blister rust, a disease, is non-native and very lethal. So if you wiped out the bark beetles but left the rust in town, the trees would still end up dead.

Its easy these days to say Climate Change is repsonsible because we all get our daily does of media, "pop-science", and opinion journalism. However, if we want to call it a Park and not a Wilderness the National Park Service must accept the responsibility of Bark Beetle good and bad.

I just returned from Glacier NP this summer where campfires were prohibited. It was astounding to see all the dead trees and the homogenous demarkation between infested and uninfested. Fire would seem to have addressed this issue sooner. Now it seems out of control.

Back in the day, we used fire quite often but now fire seems to be a bad word. Yes fire, like war, kills living things. And lots of firefighters have jobs putting them out. But if we allow fires to burn again, naturally, we could restore the integrity of the ecosystem. Now we have to consider managing our parks with expensive pesticides and application challenges rather than good old natural, albeit, dangerous fire.

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