SPATIAL ASPECTS OF BOREAL MIXEDWOOD SUCCESSION AND STAND DYNAMICS

Aspen and white spruce mixedwood forests cover a significant portion of the western Canadian boreal forest region. While both species often establish right after a fire disturbance, the faster-growing aspen soon overtops the young spruce. It may take white spruce 60-80 years to grow up through the aspen canopy. As white spruce grows into the aspen canopy, it is subjected to physical abrasion by aspen swaying on windy days. This, along with the reduced light levels can significantly reduce the growth rates and survival of the spruce. The issue of boreal mixedwood management has risen in prominence, with increased use of both aspen for paper fibre and white spruce for lumber, as well as recognition of the ecological benefits of having both species growing together on the same sites. However, viewpoints concerning how to manage these stands often differ between forestry companies that use deciduous versus coniferous trees, and substantial resources are put into manipulating species mixtures early in stand development, without a full understanding of future implications. While previous research on mixedwood forests has helped u