Q: How did the beetle-kill problem start?
A: There are hundreds of thousands of acres of mature spruce and lodgepole pine in and around the Routt National Forest. These dense stands of aging trees provide an ideal setting for a rapidly growing bark beetle infestation, which is one of several major disturbance agents responsible for regenerating the forests in this area. Wind, fire and other insects and diseases also help regenerate mature forests.
There are two beetle infestations occurring concurrently on the Routt National Forest. The spruce beetle infestation was triggered by the Routt Divide Blowdown in 1997. The downed trees created ideal habitat for a beetle population explosion. Several years later, when the blowdown trees were no longer useable, the spruce beetles started attacking nearby standing trees. The attacks on standing trees occurred in a few small areas starting in 1999, followed by large migrations from blowdown to standing trees in 2000 and 2001. Now the beetles are spreading rapidly from tree to tree in many areas of the high country.
Mountain pine beetle infestations are prevalent throughout much of Colorado, including the Routt National Forest. The Troublesome, Green Mountain, (south of Walden) Gore Pass, Independence Mountain and Steamboat Lake areas are experiencing significant mountain pine beetle numbers. The long-term severe drought in Colorado is heightening the situation.
Q: How are the beetle infestations progressing and when will they subside?
A: The number of trees being attacked and killed by spruce beetles in the vicinity of the Routt Divide Blowdown is increasing 10 to 15 times per year; for every one tree that's infested this year, there will be 10 or 15 trees infested and killed next year.
This kind of population growth is explosive. Spruce beetle outbreaks in areas more distant from large areas of blowdown are increasing as well but at a much slower pace. It's not expected that the spruce beetle outbreak will subside until there are very few large spruce trees for the beetles to attack.
A severe cold spell with little or no snow could stop the beetles but has only occurred once in the past 100 years and was responsible for stopping the spruce beetle infestation in and around the Flat Tops Wilderness in the early 1950s.
The potential for mountain pine beetle outbreaks generally is not as explosive as spruce beetle outbreaks. Mountain pine beetle outbreaks are not unique to the Routt National Forest. The Vail Valley, Arkansas Valley and the Williams Fork area also are seeing large-scale mountain pine beetle populations.
One or more years of good snow and rain likely would cause the mountain pine beetle outbreak to subside, probably until the next drought.
Q: Could these outbreaks have been prevented?
A: The underlying conditions -- hundreds of thousands of acres of mature forests making the Routt National Forest susceptible to these large-scale epidemics -- have been building for a century or more. When the blowdown occurred, most of the area outside of the Mount Zirkel Wilderness was logged to remove the food source and breeding grounds for the beetles. The U.S. Forest Service decided to salvage about 3,500 acres of the most accessible blowdown areas. Because of the difficulty of accessing some of the blowdown, the timber industry chose not to salvage about 1,000 of those 3,500 acres. The last of the blowdown salvage is occurring this summer in the Floyd Peak area.
Two-thirds of the blowdown occurred in the Mount Zirkel Wilderness. Removal of this blowdown would have been impossible before the beetles migrated to the standing trees because it would have required an act of Congress and, following that, several years to develop a transportation system into the wilderness to access the blowdown.
Taking this kind of action would have been contrary to the intent of the Wilderness Act, which includes setting aside these wild areas and allowing natural processes to occur.
Q: It sounds like the Forest Service can't stop these outbreaks. What are you doing about the situation?
A: Shortly after the blowdown, the community and the Forest Service decided to try to protect some high-value areas from the effects of spruce beetle-caused tree mortality.
These areas include the Steamboat Ski Area, all of the developed campgrounds and picnic grounds, the wildland-urban interface, scenic road corridors, dispersed recreation areas, and some timber management areas. With the spruce beetle, the infestation needs to be addressed while it's small.
Our efforts in dealing with spruce beetles consist of thinning high-value areas before beetles become established and taking aggressive actions on small outbreaks in those high value areas. Aggressive actions include cutting down infested trees and peeling them to kill the beetles.
Across the Routt National Forest, our efforts to deal with mountain pine beetle outbreaks are to thin susceptible stands before the beetles arrive and to aggressively deal with early stage and well-established outbreaks.
Because of the expanse of the infestation and the terrain in which it occurs, our ability to control large outbreaks is very limited. Beetles are always present as a natural part of the ecosystem, and epidemic proportions are cyclical depending on natural events. In this case, a 13,000-acre blowdown combined with severe drought and continued mild winters have led to conditions perfect for large-scale beetle spread.