1. Department of Biology; McGill University; Montreal Quebec H3A 1B1 Canada
2. School of Environment; McGill University; Montreal Quebec H3A 2A7 Canada
3. Departament de Ciències Ambientals; Facultat de Ciències, Universitat de Girona; Campus Montilivi 17071 Girona Catalonia Spain
4. Centre Tecnològic Forestal de Catalunya; Ctra. St. Llorenç de Morunys km 2 25280 Solsona Catalonia Spain
5. Departement of Biology; Ecology & Evolution Unit; University of Fribourg; Chemin du Musée 10 1700 Fribourg Switzerland
6. MTT Economic Research; Latokartanonkaari 9 00790 Helsinki Finland
7. Department of Botany; University of Melbourne; Parkville Dept Australia
8. School of Life Sciences; University of Warwick; Wellesbourne Warwick CV35 9EF UK
9. Environmental Agency Austria; Wien Austria
10. The Bio-Protection Research Centre; Lincoln University; Christchurch New Zealand
11. Centre for invasion Biology; Department of Botany and Zoology; Stellenbosch University; Matieland 7602 South Africa
12. Centre for Ecological Research and Forestry Applications (CREAF); Consejo Superior de Investigaciones Científicas (CEAB-CSIC); Universitat Autònoma de Barcelona; 08193 Cerdanyola del Valles Catalonia Spain
13. Estación Biológica de Doñana; Consejo Superior de Investigaciones Científicas (EBD-CSIC); E-41092 Sevilla Spain