Since the early 1980s managers have allowed many lightning-ignited fires to burn with minimal interference in forests of the Bob Marshall Wilderness in northwestern Montana, USA. We used this active fire regime to investigate fire-effects and post-fire fuel loads, tree regeneration, and forest structure in mixed-conifer forest communities.Our most important finding was that surface fuel loads are maintained or increased in the years following an initial wildfire after a long fire-free period as fire killed trees and branches fall to the ground. This unsurprising result nevertheless deserves highlighting because the current conventional wisdom is that an initial fire can be thought of as a “fuel treatment.” Our most surprising finding was the unimportance of reburnsas a cause of transitions to non-forest. Managers need to plan for multiple fire entries (i.e., two or more fires) if their goal is to use wildfires as surface fuel reduction treatments. Some transitions to a putative non-forest condition should be expected following both initial fires and short-interval reburns. Thus, managers may wish to incorporate this outcome into their expectations, and into their outreach and education efforts, in order to prepare policy makers and the public for forest conversion.

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Media Record Details

Feb 28, 2019
Andrew J. Larson
Fire & Wilderness, Recovery after fire