RED SPRUCE DEATH - EFFECTS ON FOREST COMPOSITION AND STRUCTURE ON WHITEFACE MOUNTAIN, NEW-YORK

An extensive study of the forest vegetation at Whiteface Mountain, New York was conducted to determine the effects of red spruce decline on forest composition and structure along an elevation gradient. The percent live density and the percent live basal area of all tree species were lower at elevations greater-than-or-equal-to 1000 m compared to elevations < 1000 m, but the change was most severe for red spruce (Picea rubens Sarg.). At elevations greater-than-or-equal-to 1000 m, only 47% of the standing spruce stems were alive compared to 75% live stems of associated species. The density of dead spruce was greatest in the intermediate size classes. The diameter distributions of live spruce shifted from a negative exponential form at the lower elevation bands to a nearly uniform distribution in the highest elevation band. An earlier report of substantial decreases in red spruce basal area on Whiteface Mountain was confirmed. The initial understory response to overstory spruce mortality in an old-growth stand appeared to be an increase in the abundance of balsam fir (Abies balsamea (L.) Mill.). The death of canopy spruce is an important disturbance agent in this mountain forest and could have an important influence on tree regeneration.