Post-Disturbance Changes in the Understory of an Oak Forest in Southwestern Virginia

An Appalachian oak forest, dominated by scarlet and chestnut oaks in 1971, was sampled in 1994 and again in 1999 to determine changes in density and basal area of overstory trees, changes in density and composition of understory vegetation, height growth of seedlings and saplings after disturbance by single tree gaps, primarily of scarlet oak, and general ice damage to the canopy. From 1971 to 1994, 82% of scarlet oaks died, so by 1994 the stand was dominated by chestnut oak and red maple. Changes in overstory tree density and basal area were not significant, but decline of scarlet oak was significant. This suggests that the stand is in a state of flux. Post-disturbance increases in total densities of shrubs and saplings, including white pine, were significant, as well as the increase in red maple seedlings and decline of flowering dogwood seedlings. Relative increase in height growth of white pine was also significant. Disturbance from ice damage was minor, but disturbance due to tree deaths was major. WVhite pine should become more common, but natural thinning may prevent most from reaching the canopy. The stand should be dominated in about twenty years by white pine and red maple with fewer oaks.