A largescale thinning project in Thompson Chain of Lakes State Park seeks to combat a rash of disease and pest outbreaks while reducing hazardous wildland fuels.

State officials anticipate thinning 1,000 acres in the roughly 3,000-acre park, according to a public scoping notice published Dec. 8. Stands in selected areas around Loon, Horseshoe, Crystal, Upper Thompson and Lower Thompson lakes will be thinned to obtain 8- to12-foot spacing between tree crowns, and hazardous fuels will be removed from the forest understory. 

Low intensity fires historically burned through the forests every five to 25 years. The frequent disturbance maintained open stands of ponderosa pine and western larch and ensured a consistent supply of important forage species for elk, including fescue grass.  

“Due to historic logging practices that removed mature ponderosa pine and western larch and over 100 years of fire exclusion, many stands have been converted to Douglas-fir and lodgepole pine,” reads the scoping notice. “Armillaria root disease and Douglas-fir bark beetle, coupled with drought and competition stress, have resulted [in] significant tree mortality across the Thompson Chain of Lakes State Park.” 

The proposed treatments aim to promote the development of more fire-tolerant ponderosa pine and western larch trees, reduce potentially hazardous wildfire fuels, and promote habitat for elk, deer and other wildlife species. 

Funding for the project comes from a Community Wildfire Defense Grant that the United States Forest Service awarded to the Montana Department of Natural Resources and Conservation and Lincoln County in 2023.   

The first cuts will take place this winter in the Banana Lake Unit north of U.S. 2. About 114 acres are slated for work, which will be coordinated to coincide with treatments occurring on privately owned land in a nearby subdivision. Montana Fish, Wildlife and Parks published an environmental assessment for the Banana Lake project Dec. 8. 

A timeline for further activities has not been released. The state agency is accepting comments on the project through Jan. 6. Interested parties may email comments to Dave Bennetts at [email protected]. 

Reporter Hailey Smalley can be reached at 758-4433 or [email protected].