| Bark Beetles in Colorado HOME PAGE |
According to experts on the subject, bark beetles (specifically, in this case pine bark
beetles) attack trees under stress, but healthy trees can fight them off. Recently,
prolonged drought in the southwest has left enough trees under stress that these
beetles have damaged numerous trees and threaten whole forests.
See this for Forest Service information about infestations in Arizona and New Mexico.
According to the information at the above link, a tree that has been attacked will
start to turn reddish-brown within a month. It seems that the color can vary with
specific type of beetle and time since infestation, as seen in the images here (from
similar infestations in California). There are more pictures and information here.
These beetles have been attacking far and wide, as told in this NY Times story.
That includes Colorado where all susceptible pine trees are expected to be gone in a
few years. Although drought and old age can make trees susceptible, even healthy
trees can be successfully attacked by a large enough swarm of beetles, and there is
a reason why these swarms have been growing larger. The winters are no longer cold
enough to keep the numbers down.
This ties the bark beetle problem to the warming climate. At least there is reason
to think climate change is part of the problem. This may be an example of
infestations by various pests that have been forecast to occur with climate change.
The forests may regenerate as they do after fires, but that assumes that there will
be no more pest outbreaks to interfere.
beetles) attack trees under stress, but healthy trees can fight them off. Recently,
prolonged drought in the southwest has left enough trees under stress that these
beetles have damaged numerous trees and threaten whole forests.
See this for Forest Service information about infestations in Arizona and New Mexico.
According to the information at the above link, a tree that has been attacked will
start to turn reddish-brown within a month. It seems that the color can vary with
specific type of beetle and time since infestation, as seen in the images here (from
similar infestations in California). There are more pictures and information here.
These beetles have been attacking far and wide, as told in this NY Times story.
That includes Colorado where all susceptible pine trees are expected to be gone in a
few years. Although drought and old age can make trees susceptible, even healthy
trees can be successfully attacked by a large enough swarm of beetles, and there is
a reason why these swarms have been growing larger. The winters are no longer cold
enough to keep the numbers down.
This ties the bark beetle problem to the warming climate. At least there is reason
to think climate change is part of the problem. This may be an example of
infestations by various pests that have been forecast to occur with climate change.
The forests may regenerate as they do after fires, but that assumes that there will
be no more pest outbreaks to interfere.
| There have been forecasts of increased infestation by various plant-damaging pests with the warming climate. The pine bark beetle that has been killing millions of trees in the western US and Canada could be an example of this. I became interested in this after noticing forests with as many dead trees as live ones on a recent trip through Colorado. Here are some pictures I took. Below the pictures, you will find some more discussion and some links. CLICK ON THE PICTURES FOR LARGER VERSIONS. USE THE BACK BUTTON TO RETURN. TREES AFFECTED BY BEETLES ARE COLORED RED, BROWN, OR SOME SUCH COLOR.. |
| THE PICTURES TO THE RIGHT ARE ZOOMS ON PORTIONS OF THE PICTURES ON THE LEFT I saw these trees from an overlook at the big reservoir south of Dillon and Silverthorne, Colorado. These towns are on I70 just a few miles west of the continental divide. At the top, the nearby trees seem OK, but the ones across the first bit of water are not. Signs posted in the area attributed the problem to the beetles. I can't tell about the health of the very distant trees, but their color doesn't seem to be very good. |
| Here, also at the Dillon Reservoir, there is a problem with some of the foreground trees. I can't quite tell about the trees on the mountainside in the distance, but, again, the color doesn't look good. The dead trees could increase the fire hazard in the area. |
| I got closer to these trees. They are along US Highway 6 on the approach to Loveland Pass from the west. This highway climbs rapidly from the Dillon area to the roughly 12,000 foot altitude of the summit of Loveland Pass, and I noticed scenes like this most of the way. I did not edit the color, brightness, contrast, etc of any of these pictures. I did crop them and reduce their memory size, but I did nothing else to them. I also saw many forests in Colorado that looked healthy, but this beetle is expected to spread. See more information below. |