Growth-trend declines of spruce and fir in Mid-appalachian subalpine forests

Abstract

Dendroecological (tree-ring) analysis of 258 increment growth cores collected from red spruce ( Picea rubens Sarg.), balsam fir [ Abies balsamea (L.) Mill.], and Fraser fir [ A. fraseri (Pursh) Poir.] in central West Virginia and western Virginia indicates marked declines in growth-trend during the past 20 years similar to that reported for spruce and fir in high-elevation forests of the northern Appalachians. Consequently, growth-trend declines of conifers in subalpine forest ecosystems of eastern North America are apparently more widespread than previously realized and might therefore be related to a large-scale environmental perturbation such as a change in climate or a regional-scale change in air quality. The initiation of growth-trend decline was often synchronous with the onset of a major drought, but the growth rates have failed to recover since the late 1960s when the drought ended.