Other key takeaways from the report

• Western spruce budworm – the most widespread forest pest in 2024 – continues to cause extensive and intense damage to Douglas-fir and low-elevation mixed-conifer forests.
• Western balsam bark beetle – the deadliest forest pest in 2024 – remains active in high-elevation spruce-fir forests.
• Douglas-fir beetle continues to kill Douglas-fir trees in parts of Pitkin, Fremont and Teller counties and most counties in central and southern Colorado.
• Roundheaded pine beetle and associated native bark beetles are expanding in ponderosa pine forests in the southwestern reaches of Colorado.
• Mountain pine beetle continues to impact lodgepole pine in Gunnison County and forests in the Mosquito Range in Chaffee and Park counties, as well as areas of southwestern Colorado.

“The 2025 Report on the Health of Colorado’s Forests is timelier than ever,” said Dan Gibbs, executive director of the Colorado Department of Natural Resources. “Colorado’s forests are stressed after an unprecedented warm, dry winter and are prime for further spread of mountain pine beetles and other forest health issues, along with increased wildfire risk. However, in Colorado we are taking action through the launch of the Ponderosa Mountain Pine Beetle Task Force and bringing all available resources, experts and stakeholders together to prioritize our actions to make the best science-based decisions for the future of our forests and communities.”

Resources for a deeper dive into forest health

The 2025 report contains interactive maps and data for the public and land managers to see where insects are impacting forests. To complement the report, the CSFS published three Science & Data Bytes examining the outbreak of mountain pine beetles on the Front Range, with further analyses on forest conditions, wildfire impacts and semiochemical treatments.

Each year, the forest health report provides information to the Colorado General Assembly and residents of Colorado about the health and condition of forests across the state. Information for the report comes from an annual aerial forest health survey by the USFS and CSFS, as well as field inspections, CSFS contacts with forest landowners and special surveys.