The spruce beetle has caused extensive tree damage to all species of spruce throughout the West.

Spruce Beetle Kill

2015 Aerial Survey

Spruce beetle (Dendroctonus rufipennis) outbreaks caused widespread tree mortality for the fourth consecutive year

    • Spruce beetle populations have expanded, impacting higher-elevation stands of Engelmann spruce.
    • In 2015, spruce beetle infestations were detected on 409,000 acres across the state, expanding onto 182,000 acres of previously unaffected forests.
    • Since 1996, spruce beetle outbreaks have caused varying degrees of tree mortality on more than 1.5 million acres in Colorado.
    • Blowdown events, combined with long-term drought stress, warmer temperatures and extensive amounts of older, dense spruce, have contributed to this ongoing epidemic.
Spruce Beetle in and near Rocky Mountain National Park
Spruce Beetle in and near Rocky Mountain National Park (click on map for pdf)
Spruce Beetle and Western Spruce Budworm, Southern Colo.
Spruce Beetle & Western Spruce Budworm, Southern Colorado (click on map for pdf)

Area Infested by Mountain Pine Beetle and Spruce Beetle in Colorado, 1996-2015

An adult spruce beetle on the bark of an Engelmann spruce tree. Photo: William M. Ciesla

Symptoms of Spruce Beetle Infestation

Needles on infested trees tend to drop to the ground after high winds. This can happen the second summer after the tree has been infested. Trees that have been killed by the spruce bark beetle are very dry and may create a severe fire hazard. In addition, wood products can be lost and watershed function impaired.

Management Options

Large outbreaks of the spruce bark beetle are difficult to control. Small infestations can be eliminated by quick action such as removal of infested trees. Contact a professional forester about the silvicultural, physical and chemical management practices available.

Learn More About Spruce Beetle

For more information about areas impacted by spruce beetle and other insects and diseases on Colorado’s forests, read the 2015 Report on the Health of Colorado’s Forests.