East Idaho forests threatened by Western Spruce Budworm
There’s almost always some kind of infestation or bug infecting eastern Idaho’s forests, but one little bug is causing big problems for the Caribou-Targhee National Forest.
“Our aerial detection folks out of Boise flew over the entire forest here about two weeks ago,” said Jim Robertson of the US Forest Service. “Our preliminary findings are that we have 325 thousand acres of new infestation of Western Spruce Budworm.”
Robertson said the infestation is three times as big as it was last year and six times as bad as it was two years ago. The infected tree’s can be found throughout most of the region’s forests, but they’re especially common in the mountains of Bonneville, Teton and Fremont Counties.
The budworms hatch from eggs laid by moth’s from the previous year. When they hatch, they eat all the new needle growth, and even some of the old growth on the area’s spruce and fir trees. That’s what gives the trees a brownish tinge. The infestation doesn’t kill the tree’s, but it does hurt their growth and often causes the tops of the tree’s to die.
“It’s a normal event,” said Robertson. “Sometimes the cycles last a few years, sometimes up to 10 to 15.” That natural cycle, combined with an unusually warm winter and a wet spring, created perfect conditions for a Western Spruce Budworm bloom.
Robertson said the forest service is not concerned about the long term health of the forest. In the short term, a strong winter with a 40 below event would go a long ways to limiting the number of moths, budworms, and other pests in the future.
