1. Institute of Silviculture, Department of Forest and Soil Sciences; University of Natural Resources and Life Sciences; Vienna Austria
2. Natural Resources Institute Finland; Helsinki Finland
3. School of Agriculture and Food Science; University College Dublin; Dublin Ireland
4. Forest Research, Alice Holt Lodge; Farnham UK
5. Department of Geosciences and Natural Resource Management; University of Copenhagen; Copenhagen Denmark
6. Forestry and Game Management Research Institute; Praha Czech Republic
7. Research Institute for Nature and Forest; Brussels Belgium
8. Swedish University of Agricultural Sciences; Uppsala Sweden
9. Swiss Federal Institute for Forest, Snow and Landscape Research WSL; Birmensdorf Switzerland
10. Forest Research Institute of Athens; Athens Greece