Walker Bay of Leech Lake, Minnesota with red pines and white pines. Some mature red pines dead.

MN Impact: New Rating System Accesses MN Pine Forest Stands Susceptibility to MPB

January 18, 2019

Objective

Researchers will provide new information regarding the susceptibility of pine forest stands in the region to new pests and diseases that will assist forest managers prepare for environmental changes (measured as the percent of forest stands deemed susceptible).

Issue

Mountain pine beetle (MPB) is native to western Canada but it recent years has expanded beyond its historical range and has destroyed millions of acres of trees across British Columbia and the Rocky Mountain National Park.

What has been done

Marcella Windmuller-Campione and her team set out to assess the susceptibility of pine forests in the Lake States to MPB. They developed a hazard rating system for the Great Lakes Region that uses common attributes of forest structure and composition and have assessed the current susceptibility using the Forest Inventory and Analysis (FIA) database.

Results

Results show that about 90 percent of FIA plots with at least one living pine tree are moderately to highly susceptible to MPB. Plots with a higher susceptibility had greater total plot density and pine density, while lower susceptibility was associated with greater tree diversity within the plot. Notably, plots on federally owned lands also were more highly susceptible than private and state-owned plots.

This information will assist forest managers as they develop silvicultural prescriptions and plan for the arrival of mountain pine beetle to the region.