1. Faculty of Forestry, University of British Columbia; Vancouver British Columbia V6T 1Z4 Canada
2. Department of Environmental, Population, and Organismic Biology, Box 334; University of Colorado; Boulder Colorado 80309
3. Pacific Forest Products Ltd., Saanich Forestry Centre; 8067 East Saanich Rd., R.R. #1 Saanichton British Columbia V8M 1K1 Canada