1. Department of Environmental Sciences‐Botany University of Basel 4056 Basel Switzerland
2. Research Unit of Forest Dynamics, Research Group of Ecosystem Ecology, Stable Isotope Research Centre Swiss Federal Institute for Forest, Snow and Landscape Research WSL 8903 Birmendsorf Switzerland
3. College of Science and Engineering James Cook University Cairns Qld 4878 Australia
4. Research School of Biology, College of Science Australian National University Canberra ACT 2601 Australia
5. Institut de Recherche en Horticulture et Semences Université d'Angers, INRAe 42 rue Georges Morel 49070 Beaucouzé France