The European spruce bark beetle (Ips typographus) has caused considerable damage in many Norway spruce (Picea abies) forests in recent years, due to the dry and warm conditions that have prevailed. As at least at low elevations in Europe, the climate becomes increasingly unfavorable for spruce and the pressure from bark beetles rises, these forests are becoming more vulnerable, posing ecological challenges even in previously unaffected regions at higher elevations.
With a rising number of beetles and the difficulty of controlling large outbreaks (i.e., mitigating the damage), effective post-disturbance forest management is becoming essential. There are clear benefits of promptly removing affected trees during the early stage of a bark beetle infestation. Still, there is only a limited understanding of the potential ecological advantages and ecosystem service implications of leaving beetle-killed trees in beetle-disturbed areas.
Our research in spruce-dominated mountain forests in the Swiss and Italian Alps focuses on these challenges. We are examining the short- to medium-term impacts of post-bark beetle interventions on biodiversity potential and natural tree regeneration by analyzing site, forest, and tree characteristics. We distinguish post-disturbance management strategies such as no intervention, partial removal of bark beetle-killed trees with/without release of deadwood on the ground, and salvage logging, and include undisturbed control sites for comparison. At the conference, we will present preliminary results, following the field data collection season in summer 2025.
Given the likelihood of increasing frequency and severity of bark beetle disturbance in mountain forests, understanding their impacts and providing practical insights for sustainable forest management is essential. To effectively address these ecological challenges, efforts should focus on conserving forest biodiversity, enhancing ecosystem resilience, and promoting sustainable forest management under a changing climate.