Red spruce decline on Whiteface Mountain, New York. I. Relationships with elevation, tree age, and competition

Abstract

Detailed stem analysis and stand structure and history analyses are used to evaluate relationships between growth decline in populations of red spruce (Picearubens Sarg.) on Whiteface Mountain and elevation, tree age and size, and stand dynamics. The study sites are virgin, uneven-aged spruce-fir forests at 900 and 1100 m elevation. Most red spruce sampled exhibited substantial decreases in annual stem wood volume increment from 1964 to 1984, particularly large trees and trees from higher elevation. While larger trees exhibited more severe growth decline, there is no evidence of a direct causal link between tree age and decline. Inverse relationships between growth and competition indices are evident for periods prior to the onset of decline, but these relationships degrade during the period of growth decline; competition is not causally linked to decline. There is some indication that the decline-inciting stress was particularly severe for canopy-emergent and exposed red spruce, suggesting the action of an atmospheric stress.