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Protect trees from pine beetles before next spring

By Elizabeth Wood West with photos provided by the Colorado State Forest Service

Picture of bug

Magnified view of an adult Mountain Pine Beetle – actual size of an adult is around the size of a grain of rice.

Photo of tree with damage

“Pitch tubes” – the telltale sign of beetles, usually on the lower 25’of a tree trunk.

As you ready your trees, shrubs, and gardens for winter, take the time to carefully inspect your ponderosa, lodge pole, Scotch, limber, bristlecone, and pinion pines for signs of the dreaded Mountain Pine Beetle (MPB). This Colorado native pest has devastated thousands of acres of trees in many mountain communities including Winter Park and Breckenridge. According to Ryan Ellers with the Colorado State Forest Service, small pockets of MPBs have been confirmed in or nearby Castle Pine Village, Castle Pines, Happy Canyon, and Surrey Ridge.

Beetle activity takes place under the tree bark during fall and winter. Infested trees may turn yellow to reddish brown throughout the entire tree crown and/or pitch tubes (brown, pink, or white popcorn-shaped masses of resin) may appear on the trunk where beetle tunneling begins. Ellers said, “This is the time when adult beetles attack and lay eggs in new trees. Over the winter, the larvae will feed on the tissue under the bark and develop into adults.” Beetles will take flight around early June to late July.

MPBs will attack trees that are slow-growing due to old age, crowded or poor growing conditions, drought or fire damage, injury, or root disease. Ellers said thinning dense stands of trees during fall and winter will make them less susceptible to attack and occasional supplemental watering can help fight drought stress. Water trees during warm periods when the ground thaws out and deep freeze is not predicted for a couple days. As spring approaches, landowners may want to apply preventative spray treatments in late April into May to protect green, unattacked trees.

Colorado State Forest Service tree inspections are available for a service fee of $50. Lists of contractors for tree spraying/removal and forest health publications are available at the Franktown District Office, located at the intersection of Colorado State Highways 83 and 86.

For further information or to schedule a site visit, call 303-660-9625, Monday thru Friday from 8:00 a.m. to 4:30 p.m., or e-mail



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