Only a few pockets of high activity remain
SUMMIT COUNTY — The mountain pine beetle epidemic that spread through Colorado’s north-central mountains and other parts of the West is subsiding in Summit and Eagle counties, according to the Colorado State Forest Service.
In the end, the bugs killed about 75 percent of the mature, susceptible lodgepole pine trees in the area, according to Colorado state forester Paul Cada. In neighboring Grand County, where lodgepole forests were even more prevalent than in Summit County, between 95 to 98 percent of the trees were killed by the beetles, Cada said.
He estimated that about 60 percent of Summit County’s forest cover consisted of lodgepole pine before the beetle outbreak, with 40 percent a mix of spruce and fir (along with a sprinkling of aspen and tiny pockets of trees like Douglas fir, which grow on rocky outcrops around Swan Mountain).
Doing the math, it looks like a little more than half of Summit County’s forests survived the explosion of insects more or less unscathed, but since lodgepole was such a dominant species, the infestation has changed the landscape for decades to come.
In Summit County, populations of the insects are dropping quickly back down to background endemic levels, said Cada, who’s been working with private property owners and local officials the last few years to mitigate beetle-kill impacts like potential fire danger.
Cada explained that, in between widespread beetle outbreaks — which are a normal part of lodgepole forest ecology — it’s normal to still have small pockets of infestations here and there.
“If we’re on a Bell Curve, then we’re on the downslope,” Cada said, adding that there are still a few active pockets where the pine beetles may continue to spread, including the Crown area, near Blue River and the Tenmile Canyon area. “The populations are really starting to decline,” he added.
For the most part, the bugs have simply eaten themselves out of house and home, he said. More moisture the past few years may have strengthened some of the remaining trees enough that they were able to repel the bugs on their own. And finally, as the insects moved south and west, they encountered areas of mixed forest, where it wasn’t as easy for them to spread.
Outside the areas where there are still active populations, Cada said property owners might be able to stop spraying trees with pesticides, or perhaps limit spraying to individual high-value trees.
“If I lived there, I probably wouldn’t be spraying,” he said, adding that he wouldn’t formally recommend against spraying, saying because it’s up to individual property owners to make that decision.
Read this story in the Vail Business Journal to see what’s happening with the pine beetle in Eagle County.
Filed under: agriculture, Colorado, Environment, forest fires, Forest health, forests, pine beetles, pine beetles and wildfires, Summit County Colorado, Summit County news Tagged: | bark beetles, Environment, Forest health, Lodgepole Pine, Mountain pine beetle, pine beetles, Summit County News