Assessing regeneration dynamics post-wildfire: The role of salvage logging and site conditions in southern interior British Columbia

Abstract

Salvage logging is widely used after wildfires to recover economic value and facilitate regeneration, yet its effects on post-fire recovery remain uncertain. The 2003 McLure fire in southern interior British Columbia burned a landscape with diverse pre-fire stand structures, resulting in variability that may influence regeneration trajectories. Understanding how site conditions and salvage logging shape recovery is critical for informing post-fire management strategies. We assessed regeneration dynamics across two Biogeoclimatic Ecosystem Classification (BEC) zones—Interior Douglas-fir dry-cool (IDFdk) and Montane Spruce dry-mild (MSdm)—comparing salvaged stands that were mature pre-fire to unsalvaged stands that were immature before the fire. Using linear mixed-effects models, we examined the influence of salvage logging, ecological conditions, average age of the natural regeneration, stand density and time since planting on key regeneration metrics, including natural regeneration density and height, as well as quadratic mean diameter and mean height of planted trees. Salvage logging significantly increased natural regeneration densities, likely due to greater seedbed exposure and residual seed sources in salvaged stands compared to unsalvaged areas. However, salvage logging did not enhance the growth of natural or planted trees. Regeneration and growth patterns varied notably between subzones, with MSdm supporting more vigorous development than IDFdk. These results underscore the importance of accounting for pre-fire stand structure and ecological conditions when developing post-fire silvicultural strategies.