Long-term tree demography in old-growth forests of Huron Mts, MI from permanent-plot censuses, 1962-2009

Data set is repeated censuses of trees on nineteen 0.2-acre circular permanent plots in old-growth hemlock-northern hardwood forests in the Huron Mts. in northern Marquette Co., MI. Plots are located within a large private reserve, including about 4000 ha of never-logged, old-growth forest. Plots were first censused in 1962 and recensused in 1967 by Eric Bourdo (Michigan Technological University), with additional full censuses in 1989, 1994, 1999, 2004, 2009 by Kerry D. Woods (Bennington College). Stems measured in 1962-1967 were labelled and, beginning in 1989, all stems were mapped, allowing tracking of individual stems throughout the entire study period. 1962-1967 measurements included all stems greater than 5 in/12.7 cm diameter at breast height (dbh); from 1989 onward, stems > 5 cm dbh were mapped over entire plots, and stems > 1 cm dbh (tree species only) within a circular central sub-plot 8 m in diameter. This project was supported by the Huron Mountain Wildlife Foundation, the Andrew Mellon Foundation, and the National Science Foundation