Infestation picks up pace

Forest Service monitoring spruce bark beetle epidemic


— The spruce bark beetle epidemic in the Routt National Forest is spreading a year or two faster than expected, but trees near urban areas have not been affected, at least not yet.

The Forest Service has identified four spots in the Routt National Forest where mature spruce trees are hosting the beetles, said Andy Cadenhead, team leader for the U.S. Forest Service.

Areas around Gold Creek and Gilpin Lake, Three Island Lake, east of Floyd Peak and east of Pearl Lake are showing heavy beetle infestation.

About 1,000 spruce trees are infected in each spot, Cadenhead said.

"This is happening a little bit quicker than we expected," he said. "It might be a year or two ahead."

There are smaller outbreaks in the northwest part of the county and around the Steamboat Springs area, but they are minimized to about 20 trees.

Cadenhead said the epidemic, which could eventually kill all mature spruce trees in the forest, has spread significantly throughout the forest and is generally isolated in the four identified spots.

They are all in North Routt County, near the Routt Divide Blowdown.

"We're really not finding a lot on the ski area," Cadenhead said. "It's not coming real hard, yet."

However, officials expect the infestation to grow larger as time goes on.

The spruce beetle epidemic is due to the 1997 Routt Divide Blowdown in North Routt County, where winds exceeding 120 mph blew down about 4 million trees on 13,000 acres of Routt National Forest.

Every year, an average of one tree an acre is blown down in the forest, Cadenhead said.

Spruce beetles seek the downed trees to feed on the cambium layer under the bark while the dying trees' natural defenses diminish.

When the blowdown happened, the beetles' habitat increased dramatically, giving rise to the beetle population.

A large population of beetles doesn't need dying trees to live in. Instead, about 1,000 beetles collectively attack one standing tree, exhausting the trees' defenses and eventually killing it.

From that one tree, enough beetles will be produced to kill four other trees.

"This is not an ecological disaster," said Diann Pipher, public affairs specialist for the Forest Service. "It's only a problem because of human values."

The flight of the beetles into their host trees for the winter ended at the beginning of July. Survey crews are walking through the forest to look for new "hits" and flying overhead to look for dead or dying trees, Cadenhead said.

Officials want to track the movement of the beetles to prepare for suppression efforts.

"As those outbreaks grow and spread, it could affect areas we do suppression work on," Cadenhead said.

Suppression efforts will happen in the fall.

In a $1.2-million effort last fall, the Forest Service killed beetles at Steamboat Ski Resort, Buffalo Pass, Rabbit Ears Pass and numerous campgrounds in the Hahn's Peak/Bears Ears district of the Routt National Forest.

"Also, for historic purposes," Pipher said, "we want to document how the epidemic



Use the comment form below to begin a discussion about this content.

Requires free registration

Posting comments requires a free account and verification.