Spruce beetle kill on the rise

By Shanti Johnson
Staff Writer

The United States Forest Service (USFS) and Colorado State Forest Service (CSFS) released a report on Jan. 30 statng that, while the mountain pine beetle epidemic slowed in 2013, “the spruce beetle outbreak continues to expand.”

Each year, the USFS and CSFS conduct an aerial forest health survey in Colorado. This year, the survey showed mountain pine beetles affecting “the lowest acreage of active infestation observed in 15 years.”

Even though results seem to indicate the epidemic is on the decline, the mountain pine beetle infestation has taken its toll on the state.

According to the USFS, the pine beetles have affected “3.4 million acres in Colorado since the first signs of outbreak in 1996.”

The recent aerial survey found that spruce beetle kill rose significantly over the past two years, from 183,000 new acres in 2012 to 216,000 new acres in 2013.

Since first monitored in 1996, spruce beetles have affected more than 1.1 million acres.

According to the United States Department of Agriculture (USDA), the spruce beetle is a “native invasive” species in the San Juan, Rio Grande and other southern Colorado regional forests.

Spruce beetles target mature trees and prefer down trees over standing.

“On down (windthrown and cut) trees, spruce beetles commonly colonized the lower, well-shaded surfaces and may colonize the entire length of the trunk,” the USDA reports. The colonies will often move on to weaker standing trees.

Standing trees can survive small infestations; however, most trees in beetle kill areas will become colonized more than once and die in the process.

The USDA writes that, “Tree crowns typically remain green for up to a year after attack. By the second year, needles have faded and soon fall from the tree.”

The USDA article goes on to report that, “The aerial ‘signature’ of spruce beetle-infested spruce is not as striking or long-lasting as that of pine beetles in pines. Therefore, aerial detection of spruce beetle is extremely difficult.”

Mike Lester, state forester and director of the CSFS, was quoted in the Jan. 30 USFS report saying, “Bark beetles and other forest health concerns don’t recognize property boundaries, so it’s critical for land managers and private land owners to work together …”

As of right now, the USFS reports it has “four 10-year stewardship contracts to remove dead trees to restore forests and increase their resiliency.”

The agency also has several short-term contracts for tree removal in effect.

The USFS is still exploring uses for the removed trees. Currently, removed timber in Gypsum, Colo., is being used to produce power in a biomass plant.

The Gypsum plant is so far able to produce enough energy to power the plant and pump, and to provide an additional 10 megawatts to the Holy Cross Energy Facility.

The process of using wood chips to create electricity was explained in a Jan. 16 SUN article about the Forest Health Company in Archuleta County.

The CSFS plans to release a new quick guide on the spruce beetle by April 2013.


This story was posted on February 20, 2014.