After more than two decades, beetle kill across Southwest Colorado is finally showing signs of slowing down, but that’s only because most trees at risk have fallen prey to the massive outbreak, a recent survey shows. “The big spruce tree epidemic is definitely continuing,” said Bob Cain, regional entomologist for the U.S. Forest Service. “But it’s slowing down because it’s running out of suitable trees.” Every year, the Forest Service, in partnership with the Colorado State Forest Service, conducts an aerial survey over most of Colorado’s estimated 24.4 million acres of forested lands, tracking new areas where beetle kill has spread. In Southwest Colorado, the spruce beetle epidemic started on Wolf Creek Pass in the late 1990s. Though beetles are native to the land, the insects’ toll was exacerbated as drought, warmer winters and dense forests created perfect conditions for rapid spread. Over the past two decades, the spruce beetle has torn through more than 884,000 acres – about 25% – of the Rio Grande and San Juan national forests, which, combined, total about 3.6 million acres, though not all of that land is spruce forest. In 2019, flights over the San Juan Mountains found 16,000 acres of active infestation, and of that amount, about 5,000 acres were newly discovered areas of beetle spread. Some of the most intensely hit areas, Cain said, were near Vallecito Lake and around Silverton. “A lot of it is still in wilderness areas, which is where a lot of spruce is at,” he said. Whereas beetle kill in past years saw astonishing advancements over the landscape, the number of acres actively affected has declined for five consecutive years. But even so, the survey noted beetles continue to expand their footprint in the remaining spots of unaffected spruce trees. To view the full article visit the Durango Herald.
