Affiliation: | School of Forestry &Wood Products,;Department of Geological Engineering and Sciences,;Department of Social Sciences, Michigan Technological University, Houghton, MI 49931, USA;;Harvard Forest, Petersham, MA 01366, USA;;Department of Botany, Duke University, Durham, NC 27708, USA;and;USDA Forest Service, North-eastern Forest Experiment Station, Department of Forestry, Iowa State University, Ames, IA 50011, USA |