Effects of the removal of overstory hemlock from hemlock-dominated forestson eastern redback salamanders

Eastern hemlock (Tsuga canadensis) is a common conifer throughout northeast ern North America. The species is threatened by the exotic hemlock woolly a delgid (HWA), Adelges tsugae; infestation by this forest pest can result in high levels of mortality of overstory trees with a resultant change in und erstory vegetation composition and structure. Pre-salvage harvesting of ove rstory hemlock results in a residual stand compositionally and structurally similar to that resulting from mortality due to adelgid infestation, excep t for the occurrence of standing or fallen dead trees in adelgid infested s tands. The vertebrate fauna of hemlock-dominated forests is poorly studied and the effects of the mortality or removal of overstory hemlock on forest fauna in these stands is unknown. This study reports the findings of a 3-ye ar study of the effects of pre- or green-tree salvage of overstory hemlock from hemlock-hardwood stands on terrestrial salamanders. The residual hemlo ck stocking was reduced an average of 60% following harvesting and the unde rstory vegetation responded vigorously. The relative abundance of eastern r edback salamanders was reduced in harvested stands but the effect was ephem eral and salamander numbers appear to be increasing within a few years of t he logging. It appears that hemlock defoliation and mortality due to HWA in festation or pre-salvage harvesting of live hemlock will result in only a b rief reduction in the principal terrestrial salamander of hemlock-dominated forests. Published by Elsevier Science B.V.