Restoring mixed forests through conversion of Norway spruce stands: effects of fencing and mechanical site preparation on performance of planted beech and natural tree regeneration

Abstract Conversion of Norway spruce ( Picea abies ) plantations to more diverse and resilient forest types is an important task for European managers in the face climate change increased focus on ecosystem services beyond timber production. However, there a lack knowledge how cost-effectively restore such forests. This study reports influence vicinity (distance) type (mixed or spruce), fencing mechanical site preparation (MSP) early performance planted beech Fagus sylvatica seedlings natural regeneration other tree species following clear-cuts southern Sweden. After 6 years, we found clear effects MSP, but not type. Fencing had positive effect height growth Scots pine Pinus sylvestris naturally regenerated birch Betula pendula , B. pubescens ). There was MSP survival beech, amount pine. We conclude that establishment greatly accelerated by active approaches as planting. In addition, combination planting species, effective promote transition mixed stands with both broadleaves conifers. represented highest cost among treatments, its cost-effectiveness depends local ungulate browsing pressure. our study, critical protect from browsing. Finally, abundant relatively unaffected treatments. With time, pre-commercial thinning will be needed maintain mixture species.