1. Department of Environmental and Biological Sciences, University of Eastern Finland, Joensuu, Finland
2. Faculty of Biological and Environmental Sciences, Ecosystems and Environment Research Programme, University of Helsinki, Lammi Biological Station, Lammi, Finland
3. Department of Biological and Environmental Science, University of Jyväskylä, Finland
4. Department of Environmental and Biological Sciences, University of Eastern Finland, Kuopio, Finland
5. Faculty of Biological and Environmental Sciences, Ecosystems and Environment Research Programme, University of Helsinki, Lahti, Finland
6. Natural Resources Institute Finland, Helsinki, Finland
7. Department of Forest Mycology and Plant Pathology, Science for Life Laboratory, Swedish University of Agricultural Sciences, Uppsala, Sweden