Two Decades of Change in a Great Smoky Mountains Spruce-Fir Forest

Abstract

BUSING, R. T., E. E. C. CLEBSCH (Grad. Program in Ecol., Univ. Tennessee, Knoxville, TN 37996-1610), C. C. EAGAR (Uplands Field Research Lab, Great Smoky Mtns. Natl. Park, Gatlinburg, TN 37738) AND E. F. PAULEY (Grad. Program in Ecol., Univ. Tennessee, Knoxville, TN 37996-1610). Two decades of change in a Great Smoky Mountains spruce-fir forest. Bull. Torrey Bot. Club 115: 25-31. 1988.-Two 0.405-ha old-growth spruce-fir forest plots established in the 1960's were resampled in 1986 to quantify changes in stand composition, structure and growth. The plots represented typical middle to upper (1750-1800 m elev.) spruce-fir zone vegetation of the Great Smoky Mountains. Recent balsam woolly adelgid (Adelges piceae Ratz.) infestation had killed almost all Fraser fir (Abiesfraseri (Pursh.) Poir.) canopy trees causing fir basal area reductions of 54 and 97%. Stand basal area decreased by an average of 28%, while red spruce (Picea rubens Sarg.) density and total sapling density increased by 132% and 93%, respectively. Fir density and sapling basal area increased in one plot, but decreased in the other. Spruce basal area values were similar over time. Enhanced radial growth of spruce canopy trees following fir mortality was not indicated by radial growth measurements. Tree species diversity changes were minor and showed no common trend between plots.