Decomposition Rates of Aspen Bole and Branch Litter

Abstract

Living trembling aspen ( Populus tremuloides Michx.) trees were felled to create woody litter in two dense stands 35 to 45 yr old growing on medium textured soils in northern Minnesota. Bole and branch sections were removed at felling and after 2, 3, 4, and 5 yr and evaluated for 10 attributes: bark cover, current-volume specific gravity (CVSG), concentrations of N, P, K, Ca, Mg, Fe, Zn, and Mn. Decline patterns were nonlinear for bark cover, apparently linear for CVSG, exponential or linear for K, P, Ca, Mg, and nondescript for Fe, Zn, and Mn. Branch N declined for 3 or 4 yr, then increased; bole N did not change markedly. Mean times observed or projected to half the original values of declining variables ranged from 1 yr for K in branches to 14 yr for CVSG in boles. Findings enable tentative estimation of large-litter contribution to nutrient turnover in aspen ecosystem studies. Forest Sci. 29:351-356.