Diameter distributions of tree species were determined for the Henry M. Wright Preserve, an old-growth forest at an elevation of 1380 m on the Blue Ridge Divide in Macon County, North Carolina. Betula lenta and Tsuga canadensis were not characterized by negative exponential or otherwise monotonically descending diameter distributions. This is probably caused by the dense cover of evergreen ericaceous shrubs which may prevent the establishment of some tree species. Magnolia fraseri, which reproduces by basal sprouting, does have a negative exponential diameter distribution. Tree seedlings occur predominantly on spatially rare microsites such as rocks, logs, and paths.