2:03pm

Wed February 20, 2013
Environment

Beyond The Bark Beetle: New Report Highlights Threats To Colorado Forests

The Colorado State Forest Service released its 2012 report on the health of the state’s forests Wednesday. The annual report highlights major insect and disease concerns across the state.

The 2012 report [.pdf] was presented by interim State Forester Joe Duda during a joint Agriculture and Natural Resources Committee hearing at the State House.

According to Duda, for the first time in recent decades, more forest has been impacted by the spruce beetle than the mountain pine beetle epidemic.

311,000 acres have been infested by the spruce beetle versus around 264,000 acres by the pine beetle. Acres impacted by the mountain beetle however continue to decline.

Duda says while this is significant, there are other disease and insect threats to trees in urban areas as well, including thousand cankers disease.

“Thousand cankers have been killing all of our walnut trees along the Front Range and we plan to lose the majority of those trees...”

The disease is spread by the walnut twig beetle and caused by the fungus Geosmithia morbid. Once it infects the trees, the disease produces tiny cankers that cause branches to wither and die. Repeated infections by the walnut tree beetle eventually lead to the tree’s death.

A walnut twig beetle.
Credit Steven Valley / Oregon Department of Agriculture, Bugwood.org

Large numbers of walnuts have died from the disease in Denver and Boulder. Last year new cases of the disease were discovered in Laporte, Pueblo, Canyon City as well as Loveland and Greeley.

During the State House hearing, Duda explained damage caused by the mountain pine and spruce beetle can be addressed through proper forest management.

“Colorado’s forest health concerns are not limited to bark beetles in high-elevation forests. We face a broad spectrum of concerns that impact our mountains, plains and urban forests. Only through sound forest management can we ensure that our future forests provide the resources and benefits that will meet the needs of current and future generations.”

Just as important, he says, is cooperation between the State Forest Service, residents within the wildland-urban interface, and the logging industry.