Canadian Forest Service Publications

Some silvicultural ecosystems in the Yukon. 1987. Stanek, W.; Orloci, L Government of Canada, Canadian Forestry Service, Pacific and Yukon Region, Victoria, BC. Information Report BC-X-293. 56 p.

Year: 1987

Issued by: Pacific Forestry Centre

Catalog ID: 2715

Language: English

Series: Information Report (PFC - Victoria)

Availability: PDF (download)

Mark record


This guide provides a key to the differentiation of eight silvicultural ecosystems, here called operational groups, contained within forest complexes in the southern Yukon. The operational groups are intended to aid the forester in designing silvicultural measures within the scope of a forest management plan, and are suitabIe for use in combination with or as the basis of forest inventories. The key to operational groups is based on 21 forest types, including wetland shrub types, identified by cluster analyses of vegetation data and by a mathematical method called ordination. To facilitate practical applications of the key, merchantability of the forest trees, incidence of permafrost, and site index were introduced into the scheme in addition to lists of characteristic plant species. To determine the operational group, a guide user must assign the forest stand in question to a tree species (spruce or tamarack, lodgepole pine, poplar or aspen) based on cover. Characteristic plant species combinations are also listed. The user then decides whether or not the trees are or will become merchantable in size, (a minimum height of 5 m at the base age of 50 years) and whether or not there is permafrost in the soil. In stands composed mainly of spruce, further divisions assign the stands according to the site index. The key is followed by interpretations to operational groups. They contain suggestions of a silvicultural nature. To aid in determining the operational group, one or several examples of forest types per operational group are presented. These examples contain stand cross sections, soil horizon views, and information on forest and plant covers, permafrost, soil types, soil texture, soil pH, and moisture regime. The site index curves for white spruce and lodgepole pine indicate the growth potential of trees on sites of different quality. In the Appendices are tables for field determination of moisture regimes of mineral soils with and without permafrost, as well as diagrams of forest types in relation to selected environmental variables, and illustrations of plants used in the key.