Spruce volume increases across Sweden – despite shrinking areas suited under future climate

Using projected habitat suitability for Norway spruce from 2005 to 2095 under two climate scenarios, researchers from Stockholm University and the Swedish University of Agricultural Sciences (SLU) have compared expected range shifts with long-term forest inventory data on spruce growing stock. The results show that in Southern Sweden (Götaland), a large share of spruce stands that existed in 2005 are projected to end up in areas that are no longer suitable for spruce by 2095.

“Under a moderate emissions scenario, by the turn of the next century 55 per cent of Sweden’s spruce forest will be located in areas not suitable for spruce in terms of climate. In a scenario with high emissions, this figure rises to 84 per cent,” says Caroline Greiser from Stockholm University, one of the authors of the study.

At the same time, observed trends in spruce growing stock between 2005 and 2020 often run counter to the projected changes in suitability, although patterns vary between counties. In addition, the growing stock of young trees is rising across all regions of Sweden, indicating that management practices are maladapted to climate change.

“Norway spruce is the backbone of Swedish forestry, but our analysis shows a growing gap between where spruce is being planted and where climate conditions are projected to support spruce growth in the long term,” says Caroline Greiser.

The study highlights a risk that forest landscapes may become more vulnerable to climate-related stress where spruce is expanded or maintained in areas projected to become less suitable. The authors argue that climate-adaptive forest planning needs to be more directly integrated into operational decisions – such as tree species choice, regeneration strategies, and long-term risk management – if Swedish forests are to remain resilient as the climate changes.

“Our findings show that planting new spruce trees in Southern Sweden comes with high ecological and economic risks as trees may face a higher pre-harvest mortality due to climate-driven stressors such as drought, windthrow or attacks from the bark beetle,” says Jeannette Eggers, co-author of the study and program director for Forest Sustainability Analysis at the Swedish University of Agricultural Sciences, SLU.

Publication

Title: Spruce volume increases across Sweden – despite decreasing future climate suitable areas
Journal: Scandinavian Journal of Forest Research
Authors: Schulte, L. A., Greiser, C., Eggers, J., Wallin Viman, M., Jarsjö, J., Schwarz, E. DOI: 10.1080/02827581.2026.2628636

Key findings

• Large projected loss of suitability in southern Sweden: By 2095, much of today’s spruce area in Southern Sweden is projected to fall outside the suitable climate envelope.
  
• Observed spruce volume trends often move the other way: From 2005–2020, spruce growing stock frequently increased where future suitability is projected to decline, with variation among counties.
  
• Young spruce is increasing everywhere: The growing stock of young trees is rising across all regions of Sweden, indicating management practices are maladapted to climate change