1. Research and Collections Center, Illinois State Museum, 1011 East Ash Street, Springfield, IL 62703, USA
2. Department of Forest Sciences, University of British Columbia, Vancouver, B.C. V6T 1Z4, Canada
3. Botanical Museum, University of Oslo, Sarsgt. 1, N‐0562 Oslo, Norway and Norwegian Institute of Land Inventory, P.O. Box 115, N‐1430 Ås, Norway
4. Institute of Biology and Soil Science, Russian Academy of Sciences, Vladivostok 690022, Russia
5. Ministry of Natural Resources, Northeast Science and Technology, P.O. Bag 3020, Hwy 101 East, South Porcupine, ON P0N 1H0, Canada