1. Section of Wood Protection and Biotechnology, Wood Laboratory, Swiss Federal Laboratories for Materials Testing and Research (EMPA), Lerchenfeldstrasse 5, 9014 St Gallen, Switzerland;
2. Albert‐Ludwigs‐Universität Freiburg, Professur für Forstbotanik, Bertoldstrasse 17, 79085 Freiburg i. Br., Germany