Bark beetles have affected millions of acres of western forests and sometimes contribute to highly unpredictable fire behavior. Fire fighters are increasingly being exposed to fires burning in mixtures of dead and live trees in bark beetle-impacted forests, yet there is limited understanding of bark beetle effects on fire behavior.
Two new physics-based models, The Wildland Fire Decision Support System (WFDSS) and HIGRAD/FIRETEC, are providing insights into how and why bark beetle-caused tree mortality affects fire behavior in ways that operational models cannot. For example, these models can provide insights into how fires might behave under fluctuating winds, in mixtures of varying fuel moistures such as bark beetle affected forests, or in areas with a heterogeneous distribution of surface and canopy fuels. For more information, see Progress in understanding bark beetle effects on fire behavior using physics-based models.
Physics-based fire models are providing insights to better understand how and why bark beetle caused mortality alters fire behavior and identify “watch out” situations for fire fighters.
Research to date has revealed that bark beetle-impacted forests can exhibit rapid rates of spread through time even under moderate fire weather conditions with relatively low winds.
This work is helping to inform current and future land managers whom are dealing with large areas impacted by bark beetles as well as guide new experiments and measurements related to the effects of bark beetle mortality on fire behavior.