Ice storms and forest succession in southwestern Virginia

The effects of heavy glaze on damage, mortality and reproduction patterns of trees were studied in four forests, two growing seasons after a major winter ice storm Most oaks and hickory were resistant to glaze, while black oak (Quercus velutina), yellow poplar (Liriodendron tulipifera) and pines (Pinus spp) were not, with three-quarters or more of the trees damaged by ice For most species, per cent damage and mortality were positively correlated, but they were negatively correlated for red maple (Acer rubrum) and yellow poplar, which experienced extremely low mortality rates Density of tree reproduction increased after disturbance The effect on succession was complicated by site factors and the successional status of disturbed forests. Forests occupying xeric sites (Quercus spp., Pinus pungens, Pinus rigida) were least affected since overstory-understory species composition remained virtually unchanged On more mesic sites, succession was (1) accelerated in Virginia pine forests, where extensive canopy damage and mortality allowed rapid growth of oak reproduction established before the storm, and (2) probably retarded in yellow poplar forests because of the low mortality of canopy trees and stimulation of yellow poplar seedling reproduction