Forest Investment Account (FIA) - Forest Science Program
FIA Project Y072183

    Assessment of the effectiveness of green tree retention in maintaining the diversity of and promoting the recolonization by ectomycorrhizal fungal species into harvested areas of coastal forest
Project lead: Trofymow, J.A. (Tony)
Contributing Authors: Lucarotti, C.J.; Morin, B.; Graham, R.I.; Lapointe, R.; Outerbridge, Renata A.; Trofymow, J.A. (Tony); Canadian Forest Service
Imprint: [BC] :, 2007
Subject: Forest Investment Account (FIA), Ectomycorrhizae, British Columbia
Series: Forest Investment Account (FIA) - Forest Science Program
Ectomycorrhizal (EM) fungal species are an important component of biodiversity for assessing the effects of variable retention (VR) forestry. In our previous work (Trofymow and Outerbridge C.J. Bot. 2004 in press) on south Vancouver Island (Weyerhaeuser’s Shawnigan and Nanaimo River Operations) we found clear evidence of edge effects in VR sites. We observed significantly lower abundance and diversity of EM fungi with increased distance from the retained forest patches. In this proposal we extend our research to examine how rapidly EM fungi from retained trees recolonize the regenerating forest, by studying different ages of reforested matrix, and examine a Variable Retention Adaptive Management (VRAM) experimental site with different levels of individual green tree retention. The VRAM experiments are the foundation of Weyerhaeuser’s AM program. Each site has 4 or 5 treatments: clearcut, uncut (old growth or 2nd growth), and two or three variable retention alternatives (20 ha minimum size for each treatment). Our proposal is consistent with the FSP Sustainability Program in that it addresses at least one of its priority themes i.e. 1.4 :'Effectiveness of stand-level structures and habitat in maintaining biodiversity’. Our research will fill some key knowledge gaps related to current stand-level harvesting practices in both old and immature stand and specifically address the questions: 1. Assuming that retained forest patches serve as refugia for EM fungi, creating an edge effect at the tree line/clearcut boundary with regards to their abundance and diversity (Trofymow and Outerbridge 2004), how quickly do EM fungi re-colonize the adjoining reforested areas, and are there changes to the species composition? 2. Does the reforested matrix assume the pre-harvest level of EM fungi with time? What rotation age of Douglas-fir stands should be used to maintain the pre-harvest biodiversity of EM fungi? 3. What level of retention is required to meet habitat needs of mature Douglas-fir EM fungi and to maintain their pre-harvest diversity? Does single-tree retention play a useful role? 4. How effective are Weyerhaeuser’s forest management practices in creating and maintaining the variable retention levels, especially the levels needed to successfully protect EM fungi? 5. Are commercially important EM macrofungi eg. chanterelles or pine mushrooms, present in the retained mature stands? How do different levels of retention and time affect their recovery?
Related projects:  FSP_Y061183FSP_Y083183


Can. J. Bot. 82:1671-1681
Information Forestry Newsletter - April 2007
Executive summary (75Kb)

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