1. Department of Botany Institute of Ecology and Earth Sciences University of Tartu Lai 40 51005 Tartu Estonia
2. Department of Biological Sciences University of Alberta Edmonton AB T6G 2E9 Canada
3. German Centre for Integrative Biodiversity Research (iDiv) Halle‐Jena‐Leipzig Deutscher Platz 5e 04103 Leipzig Germany
4. Department of Genetic Ecology Institute of Botany Academy of Sciences CZ‐25243 Pruhonice 1 Czech Republic
5. Research Unit “Ecosystèmes Biodiversité, Evolution” («UMR 6553») Centre National de la Recherche Scientifique University Rennes 1 Campus Beaulieu, Bâtiment 14 A 35042 Rennes France
6. Alterra, Wageningen UR (University & Research Centre) PO Box 47 NL‐6700 AA Wageningen The Netherlands