Dead and dying trees focus of Colorado’s forest survey

The bark beetle infestation affected about half a million new acres in 2007, bringing the total number of acres of infestation to 1 million since the first signs of outbreak in 1996, report the Colorado State Forest Service and U.S. Forest Service in their annual forest health aerial survey.

Dead and dying trees that were isolated to five northern Colorado counties last year now extend to the Front Range as well as southern Wyoming, said Rick Cables, Rocky Mountain Regional Forester for the U.S. Forest Service. "Working with our many partners to mitigate impacts to high-value areas from the bark beetle epidemic is a top priority."

Although bark beetles are a natural part of lodgepole pine ecosystems, warm winters and recent droughts have intensified the problem and provided an environment for the beetles to multiply and spread.

Aerial survey results

• Most of the lodgepole forests in Colorado have some level of tree mortality caused by the mountain pine beetle.
• In many areas across Colorado, generally north of Leadville, the epidemic in lodgepole pine has expanded and intensified.
• Mountain pine beetle damage reached epidemic levels in high-elevation lodgepole pine forests in Boulder, Chaffee, Clear Creek, Gilpin, Lake, and Larimer counties. Both Boulder and Larimer counties documented a 1,500 percent increase in beetle activity in the past year.
• At the current rate of tree mortality, the mountain pine beetle epidemic will likely kill the majority of Colorado's large-diameter lodgepole pine forests within the next 3-5 years.

Other emerging forest health concerns

• Active spruce beetle outbreaks are occurring in Englemann spruce throughout Colorado.
• Defoliating insects such as western spruce budworm and western tent caterpillar are found in high numbers in southern Colorado forests; the Douglas-fir tussock moth continues to affect trees in the Front Range.
• Aspen tree decline is a concern. Many of the mature aspen trees are more susceptible to natural stresses and are dying due to drought, defoliation, and disease.

Legislation recently introduced and passed by Colorado's state and federal legislators has directed much-needed funding for priority projects in critical areas to protect lives, property, and forest health.