The spread of the mountain pine beetle epidemic, which has swept through forests across Colorado since 1996, is slowing significantly, according to the state's recently released annual aerial forest health survey.
The U.S. Forest Service and Colorado State Forest Service reported that the epidemic has expanded by 31,000 acres in 2012, as compared to the 140,000-acre increase in 2011.
"Generally speaking, the mountain pine beetle epidemic in Summit County is definitely declined," said Cary Green, U.S. Forest Service timber management assistant for the White River National Forest eastern zone. "We haven't seen any widespread damage since 2009/2010. I think Summit County's clear in that."
Though the epidemic is declining, Green said that it doesn't mean the beetles are gone completely. It will be possible for pockets of trees to be affected in the future.
"They're always going to be in the ecosystem," he added.
Nearly 3.4 million acres in Colorado have been infested by the mountain pine beetle since the initial outbreak in 1996. Most mature lodgepole pine trees have now been depleted within the initial epidemic area.
Mountain pine beetles aren't the only insect causing havoc on Colorado's trees, however. While the pine beetles seem to be in decline, the recent report stated that the spruce beetle outbreak has started to expand. Nearly 1 million acres have been affected since 1996, including 183,000 additional acres detected in 2012.
The majority of the spruce beetle devastation has occurred in southern Colorado in the San Juan and Rio Grande national forests. Though spruce beetles have shown up in Summit County, Green said they do not appear to be in very large numbers.
Unlike mountain pine beetles, which attack standing trees, spruce beetles prefer fallen trees, where they build up their population before attacking nearby weaker trees. Similar to mountain pine beetle, the increase in spruce beetle activity is due to factors that increase tree stress, including densely stocked stands, ongoing drought conditions and warmer winters.
According to Green, spruce beetle infestation is harder to spot, because the needles simply fall off rather than change color as with the mountain pine beetle.
Green said that the main focus right now is to deal with the remnants of the beetle kill as well as increase the health of the forest to make it less susceptible to future beetle attacks, of any kind.
"(We're) trying to get most of the dead trees out where we can, trying to utilize the trees in some sort of product so they don't go to waste," Green said. "And regenerating the next future forest is obviously the goal as well."
This will come in the form of planting trees in areas of high use, such as recreation areas. In other parts, Green said, lodgepole trees will start to come back on their own, particularly younger trees that survived the beetle epidemic and are therefore much less likely to succumb to beetles i