Post-storm management determines early tree species composition and browsing intensity in regenerating beech forest

Abstract

Natural disturbances such as fire, insect pests, and windstorms are affecting forests with increasing intensity. Fallen and damaged trees are commonly removed by salvage logging, which can affect tree regeneration and browsing pressure. Yet, the interaction of logging intensity and browsing and their cumulative effects on natural tree regeneration remain poorly understood. We applied three treatments of differing logging intensity to temperate beech (Fagus sylvatica) forest affected by windstorm, using adjacent undamaged forest as reference. We monitored tree regeneration for the first four years following disturbance, and browsing on experimentally planted one-year-old Quercus robur saplings for one year on a total of 20 plots. Natural tree regeneration was present on all plots, regardless of treatment. Species richness and cover of natural regeneration did not differ between disturbance treatments, tree species composition shifted towards early successional species with increasing management intensity, i.e., decreasing amount of deadwood remaining on-site. Community composition of regenerating trees on plots with intensive logging was significantly dissimilar to undamaged forest. Browsing intensity by roe deer decreased with decreasing logging intensity. Browsing by voles and mice showed the opposite effect direction. We show that salvage logging intensity influences species composition of natural regeneration, and that dead wood retention modulates browsing. Salvage logging of moderate intensity promotes the regeneration of early- and late-successional tree species similarly, thereby reducing the need for afforestation.