1. College of Forestry and Conservation; University of Montana; Missoula MT 59812 USA
2. Division of Biological Sciences; University of Montana; Missoula MT 59812 USA
3. Institute of Systematic Botany; University of Zürich; Zollikerstrasse 107 CH-8008 Zürich Switzerland
4. Albrecht von Haller Institute of Plant Sciences; University of Göttingen; Untere Karspüle 2 D-37073 Göttingen Germany