Forest fires of low and moderate intensity often do not constitute a direct lethal threat to mature trees, but rather may leave behind trees with a variety of injuries, subsequently affecting their physiology. Post-fire physiological processes and linking specific heat injuries to impairments of whole-tree functioning are the focus of intense current research. Recent studies suggest that, besides cambium and phloem necrosis, also fire-induced xylem dysfunction plays an important role in post-fire tree physiology.

We analyzed the importance of bark insulation for the protection against fire-induced impairments of tree hydraulics and integrated potential hydraulic dysfunctions into a conceptual framework, which explains post-fire physiological processes, their interactions and possible feedbacks. Further, we monitored stem diameter variations and basal area increments of injured trees in the years after a fire to understand the effects of heat-initiated hydraulic limitations on tree functionality and growth.

Considering climate-driven changes in fire activity, knowledge on post-fire tree responses will become increasingly important to better estimate respective ecosystem dynamics and interactions with other disturbances such as drought events or biotic attacks.

This event was part of the Missoula Fire Sciences Laboratory 2021-2022 Seminar Series