Division of Forestry and Natural Resources, West Virginia University, 322Percival Hall, PO Box 6125, Morgantown, WV 26506, USA;
USDA ForestService, Northern Research Station, 5985 Highway K, Rhinelander, WI 54501,USA;
Ontario Forest Research Institute, 1235 Queen St. E, Sault Ste. Marie,ON P6A 2E5, Canada;
USDA Forest Service, Northern Research Station, 271Mast Road, Durham, NH 03824, USA;