53 YEARS OF CHANGE IN AN UPLAND FOREST IN SOUTH-CENTRAL NEW-YORK - GROWTH, MORTALITY AND RECRUITMENT

The contributions of growth, mortality and recruitment to long-term changes in the composition and structure of an Allegheny northern hardwood forest were quantified for a set of four permanent plots in south-central New York. Increment cores, taken from all trees - 10 cm dbh, indicated that more than half (53.3%) of the stems inventoried in 1935 died before 1988. Mortality was highest on an unthinned plot (62.8%) and least (37.5%) on the plot with the lowest initial basal area. Mortality was highest for the short lived, shade intolerant species (e.g., black cherry [100%] and black birch [83%]) and lowest for longer lived, more shade tolerant species (e.g., sugar maple [34%] and beech [51%]). Relative growth rates of overstory trees were significantly lower on an unthinned plot than on three thinned plots for two decades after thinning. Sugar maple appeared to be the most responsive species to thinning. Growth rates of basswood declined markedly from 1930-1987. These results suggested that sugar maple would continue to dominate these plots while basswood and beech would become less important in the future forest.