A global review of Sitka spruce (Picea sitchensis Bong. Carr.): challenges and opportunities in European modern forest management

Sitka spruce (Picea sitchensis Bong. Carr.) is one of the most important non-native conifer species in European forestry, particularly in Northwest Europe. Originally from the Pacific Northwest of North America, it has been widely introduced because of its rapid growth, high quality of timber and adaptability to a range of environmental conditions. This literature review examines the silvicultural characteristics, ecological requirements, production potential and environmental impacts of Sitka spruce in Europe. The species is valued for its economic benefits, as it contributes significantly to timber production and carbon sequestration. On suitable sites, Sitka spruce has the potential to achieve higher timber production than native Norway spruce (Picea abies L. Karst.). However, the species is highly sensitive to prolonged periods of low soil moisture, and future drought-prone conditions under climate change may severely affect its health, growth, and long-term productivity. Its widespread planting has raised concerns about biodiversity loss, windthrow susceptibility, and vulnerability to pests and diseases, particularly bark beetle outbreaks, which are expected to increase in frequency and severity under climate change. Sitka spruce demonstrates a high ecological valence, allowing it to thrive across various soil types and climatic conditions, although its resilience to climate change remains a subject of ongoing research. Mixed-species management with other conifers and broadleaves is recommended to enhance stand stability, reduce pest vulnerability, and improve ecological resilience. This review highlights management strategies, including thinning regimes and mixed-species stands, to optimize growth while mitigating ecological risks. The study provides a comprehensive evaluation of the challenges and opportunities associated with Sitka spruce in modern European forestry and offers insights into evidence-based and climate-adaptive forest management strategies, particularly for new regions with suitable moisture conditions.