Regenerating Boreal Mixedwoods : Three – year results of a Group Shelterwood Silviculture System in Trembling aspen – White spruce Stands

• Extension • Research • Consulting • PHOTO 1. Boreal mixedwood stand where both aspen and white spruce are within the dominant and co-dominant crown classes. Mixed species stands provide options for creating a wide variety of future stand conditions. Forest managers are increasingly being asked to consider and apply a diversity of silviculture systems to address the variety of social, economic and ecological values found in forest ecosystems. A widespread and distinctive feature of the boreal forest are mixed stands of white spruce and trembling aspen, often referred to as ‘mixedwoods’. These can be horizontal mixtures of white spruce and aspen trees (Photo 1) or vertical mixtures where the white spruce are growing under taller aspen (Photo 2). An almost infinite number of combinations can be found, reflecting the type and intensity of disturbance, vegetation on site, seed sources and ecological characteristics of the plant species (Lieffers et al. 1996). The Canadian Forest Service established a number of partial cutting trials in the boreal mixedwoods of western Canada between 1924 and the mid 1960’s (e.g. Ball and Walker 1995, 1997, Lees, 1964, 1970, Waldron 1959). Natural regeneration of white spruce was the focus of many of these earlier experiments. Recently, there has been a resurgence of interest in alternative silviculture techniques in response to ecosystem based approaches to forest management. The purpose of this research note is to describe the third year results of application of a group shelterwood system in boreal mixedwood forests in the Fort Nelson Forest District of northeastern British Columbia. Study Area