1. Research Group of Plant and Vegetation Ecology; Department of Biology; University of Antwerp; Wilrijk B-2610 Belgium
2. School of Earth and Environmental Sciences; Faculty of Science and Engineering; James Cook University; Smithfield 4878 QLD Australia
3. Department of Environmental Sciences; Faculty of Agriculture and Environment; The University of Sydney; Sydney 2015 NSW Australia
4. Swiss Federal Institute for Forest, Snow and Landscape Research (WSL); Birmensdorf 8903 Switzerland
5. School of Plant Science; University of Tasmania; Locked Bag 55 Hobart Tasmania 7001 Australia
6. Department of Chemical and Biochemical Engineering; Technical University of Denmark; Kgs Lyngby 2800 Denmark
7. Rangeland Resources Research Unit; USDA-ARS; Crops Research Laboratory, 1701 Centre Ave Fort Collins CO 80526 USA
8. Department. of Horticultural Sciences; Texas A&M University; TAMU 2133 College Station TX 77843 USA
9. Department of Forestry and Natural Resources and Department of Biological Sciences; Purdue University; 715 West State Street West Lafayette IN 47907-2061 USA
10. Department of Forestry and Environmental Resources; North Carolina State University; Raleigh NC 27695 USA
11. Forest Ecology; Department of Environmental Sciences; ETH Zurich; Universitätstrasse 16 Zurich CH-8092 Switzerland
12. The Institute of Botany; University of Basel; Schönbeinstr Basel 6CH-4056 Switzerland
13. Southern Swedish Forest Research Centre; SLU; P.O. Box 49 Alnarp SE-230 53 Sweden
14. Department of Botany and Microbiology; University of Oklahoma; Norman OK 73069 USA
15. Division of Environmental Science & Policy; Nicholas School of the Environment; Duke University; Durham NC 27708-0328 USA
16. The Department of Forest Ecology & Management; Swedish University of Agricultural Sciences (SLU); Umeå SE-901 83 Sweden
17. DIBAF Department for Innovation in Biological; Agro-food and Forest systems; University of Tuscia; Via San Camillo de Lellis Viterbo I-01100 Italy
18. David Tingey; 425 NW Merrie Drive OR Corvallis 97330 USA
19. Department of Environmental Sciences; Earth System Science - Climate Change; Wageningen University; P. O. Box 47 Wageningen 6700AA The Netherlands