1Department of Forest and Conservation Sciences, Faculty of Forestry, University of British Columbia, Forest Sciences Centre, Vancouver, BC V6T 1Z4 Canada
2Department of Dendrology and Forest Tree Breeding, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences, Prague, 165 21 Czech Republic
3Saskatoon Research and Development Centre, Agriculture and Agri-Food Canada, Saskatoon, SK S7N 0X2 Canada
4United States Department of Agriculture-Agricultural Research Service (USDA-ARS), Corn and Soybean Research, Wooster, OH 44691 USA
5Department of Wood Science, Faculty of Forestry, University of British Columbia, Forest Sciences Centre, Vancouver, BC V6T 1Z4 Canada
6Département des sciences du bois et de la forêt, Faculté de foresterie, de géographie et de géomatique, Université Laval, Québec, QC G1V 0A6 Canada
7Department of Botany, University of British Columbia, Vancouver, BC V6T 1Z4 Canada
8Present Address: Scion (New Zealand Forest Research Institute Ltd.), Whakarewarewa, Rotorua 3046 New Zealand
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