Colorado’s trees have actually been under attack for thousands of years from native bark beetles. Despite local appearances, Southwest Colorado and the San Juan National Forest have been relatively lucky so far.

Three types of bark beetles have been laying eggs in, eating bark and killing Colorado trees. The mountain pine beetle feeds largely on lodgepole, ponderosa and limber pine and is responsible for the dramatic and widespread kills in northwest Colorado. Spruce beetles target Engelmann spruce, and Ips beetles feed on piñon pine.

The San Juan National Forest has dodged devastating

mountain pine and spruce beetle kill to date. “We do have a lot of beetle activity on the forest,” explained Dave Dallison, timber program leader for the San Juan National Forest. “But because we have a lot of variety in our species and broken terrain, we don’t get a lot of widespread kills. Probably the biggest risk we have is to the ponderosa pine on the west side of the forest near Pagosa Springs.”

However, one bark beetle has hit Southwest Colorado especially hard, according to Bill Romme, professor of fire ecology at Colorado State University. Ips beetles have decimated much of the piñon tree population in

the region.

“The most striking thing in the Durango area is the amount of piñon die-off,” Romme said. “Millions of the piñon trees have died because of that outbreak, and that’s one area I actually worry about when I look all over Colorado.”

Romme said that he suspects that Ips beetles are flourishing locally not merely because of ongoing drought conditions, but because of unusually high temperatures as a result of global warming.

– Will Sands