Skip to main content
SLU publication database (SLUpub)

Research article2002Peer reviewed

Natural regeneration of Norway spruce, Scots pine and birch under Norway spruce shelterwoods of varying densities on a mesic-dry site in southern Sweden

Nilsson, Urban; Gemmel, Per; Johansson, Ulf; Karlsson, Matts; Welander, Torkel

Abstract

The effects of shelterwood density and site preparation on the emergence, survival and growth of naturally regenerated Nor-way spruce (Picea abies L. Karst.), Scots pine (Pinus sylvestris L.) and birch (Betula pendula Roth and B. pubescens Ehrh.) seedlings were investigated in Norway spruce shelterwoods in southern Sweden over a 6 year period. The shelterwood densities ranged from 277 to 96 stems/ha and an adjacent clear-cut. Scarification increased the emergence of all species. Increased shelterwood density promoted the emergence of Norway spruce seedlings, while the emergence of Scots pine and birch seedlings were not significantly affected by the shelterwood density. The survival of birch was negatively correlated to increased shelterwood density, while the survival of Norway spruce and Scots pine were less affected. Soil scarification had no significant effect on the survival of Scots pine and birch. In Nor-way spruce, the survival was higher in mineral soil than in undisturbed soil. Seedling growth decreased with increased shelterwood density for all species. Removal cutting of shelterwoods produced a high mortality in Norway spruce and Scots pine, but not in birch. The Norway spruce seedlings were evenly distributed throughout the shelterwood, whereas Scots pine and birch seedlings appeared in patches. Findings from this study indicate that a mixed-species forest may be established by using the following natural regeneration method: a sparse shelterwood, combined with scarification. Then, the future tree species mixture can be controlled through pre-commercial thinning and, if necessary, by complementary planting. (C) 2002 Elsevier Science B.V. All rights reserved.

Keywords

silviculture; scarification; Picea abies; Pinus sylvestris; Betula sp.

Published in

Forest Ecology and Management
2002, Volume: 161, number: 1-3, pages: 133-145
Publisher: ELSEVIER SCIENCE BV