It was a hard day's winter for wildlife, but the beetles in the Dixie National Forest loved it.
Like a blanket of insulation, the deep snow protected the beetles, burrowed cozily in the trees, from one of their biggest natural enemies: springtime freezes. As a result, the spruce bark beetle and the pine bark beetle populations are healthier than ever.That's bad news for spruces and ponderosa pines, which are still stressed from a 10-year drought. About 2,000 acres of trees are under attack, primarily in the Cedar Mountain area between Cedar Breaks National Park and Panguitch Lake in Garfield County, said Mark Van Every, Dixie public affairs officer.
"This is like a slow-moving forest fire," Van Every said.
In economic terms, the bugs are threatening about 3 million board feet of timber valued between $1.1 million and $2.4 million.
"Most areas are relatively close to roads and subdivisions that have homes on them, so we're concerned not only for the trees but also the effect on the trees on private lands," Van Every said.
Forest Service entomologists first noticed late last year that the beetle populations were increasing. "When we were finally able to get in (this spring) and do some surveys, we realized that the problem was significant and we needed to address it."
The beetles feed on the cambian layer of the bark, weakening the tree and potentially causing its death. Trees normally fight off insects by secreting sap, but the years of drought have caught the trees with their "immune systems" down.
Dixie managers are discussing ways to combat the infestation.
One strategy is to remove trees that are infested with larvae before the bugs turn into flying beetles that can infest other trees.
"We're looking at the possibility of helicopter logging so we wouldn't have to build new roads," Van Every said. "It's expensive but right now the timber prices are high enough that it could be economic feasible."
Insecticides is another strategy as is selectively reducing the number of trees to lessen the trees' competition for water, nutrients and sunlight, thus allowing the remaining trees to strengthen their natural defenses against the insects.
Other strategies call for spraying beetle pheromones (sexual hormones) on a "sacrificial tree" to attract a large quantity of beetles. The tree is then removed and the beetles destroyed.
Friends of Dixie National Forest, an environmental watchdog group, was unaware of this particular infestation until Thursday, when Stan Boicourt, who heads the group, met with Dixie Forest supervisor Hugh Thompson to "talk about bugs."
Friends of Dixie is generally opposed to the rate of logging on the Dixie, believing that the 26 million board feet of timber cut each year should be reduced to 7 million.
Boicourt said Dixie forest managers are known for using infestation as an excuse to sell more timber.
Van Every denied that charge, saying Dixie could allow the infestation to run its course naturally. "But that's not consistent with Forest Service management goals, which are to supply natural resources to the country.
"In this particular circumstance, what we're saying is: In order for us to manage this area and not allow a large population of trees to be killed, we've got to do something."