1. Natural Resources Canada, Canadian Forest Service, Pacific Forestry Centre, 506 West Burnside Road, Victoria, BC V8N 2S6, Canada.
2. Natural Resources Canada, Canadian Forest Service, Laurentian Forestry Centre, 1055 du P.E.P.S., P.O. Box 10380 Stn. Sainte-Foy, QC G1V 4C7, Canada.
3. Université du Québec à Montréal, Centre d’étude de la forêt, C.P. 8888 Stn. Centre-ville, Montréal, QC H3C 3P8, Canada.
4. Natural Resources Canada, Canadian Forest Service, Northern Forestry Centre, 5320 122nd Street, Edmonton, AB T6H 3S5, Canada.