Project Code: WEYDV-02-086
Program: FRIP
Project Status:Completed


Object & Deliverables

The project attempted to quantify aspects of “old growth” forests in Drayton Valley so that appropriate levels of these forests could be maintained in the landscape. A study was instituted to understand the differences in structure and composition of forests of various ages and topographic site conditions. Ninety five sampling plots in a 123 square kilometer study area in the Upper Foothills and Subalpine Natural Subregions were sampled for vegetation structure and composition for stands ranging in age from 70-300 years. An old growth index was developed that took into account multiple attributes. Results indicate that specific attributes including snag basal area and density, decay stage and density of downed material, variation in live tree age and variation in live tree height and age separate a younger forest from an older one and hence may describe “old- growth conditions”. The age of onset of these old0growth attributes is variable but appears to occur between 160 and 180 years. Key factors other than stand ge that contribute to or modify the development of old-growth attributes are elevation and moisture regime.

Final Report

The final report was presented as a paper in The Forestry Chronicle, vol 79, no.3, May/June 2003, entitled, “Differentiating mature and old-growth forests in the Upper Foothills and Subalpine Subregions of west-central Alberta”, by Luigi E. Morgantini and John L. Kansas.