Forecasting Impacts of Mountain Pine Beetle on Lodgepole Pine Forests

Rocca, Monique

We investigated how subalpine forest structure and composition are likely to respond to combinations of climate-induced stresses brought by insect epidemics, changing fire regimes, and their interactions. Lodgepole pine forests have experienced a severe, drought-induced outbreak of the mountain pine beetle in recent years, raising concerns amongst land managers and the public about the wildfire hazard posed by insect-killed trees and what will grow where vast lodgepole pine stands once stood. It is widely believed that insect outbreaks set the stage for catastrophic wildfires because they create great quantities of dead fuels. There is considerable uncertainty regarding how the current mountain pine beetle outbreak will impact future fire behavior in beetle-killed stands. However, it is thought that the risk of a crown fire may be greater in stands composed primarily of standing dead trees with red needles than in stands of green trees. We accomplished the following objectives: We characterized landscape patterns of lodgepole pine mortality, serotiny, and the diversity of forest/woodland stand structures following the mountain pine beetle outbreak in Rocky Mountain National Park. We focused on the factors affecting the survival and the regeneration of tree species. We tested interactions between insect-induced tree mortality and wildfire behavior. We utilized prescribed fire in beetle-impacted stands to investigate the flammability of lodgepole pine crowns. Utilizing forest simulation models, we predicted forest developmental trajectories 100 years into the future.

Forecasting Impacts of Mountain Pine Beetle on Lodgepole Pine Forests

Collections