PARENT SESSION
Poster Session #32: Plant Ecology I.
Wednesday, August 8, 2001. Presentation from 3:30 PM to 5:00 PM. Exhibition Hall
144
Relationships between herbaceous understory and canopy type in a northeastern Wisconsin forest.
Hodgson, James1, Hodgson, Jay2, Podlaha, Ondrej1, Bunker, Gregory3, 1 2 3
ABSTRACT- The composition of the herbaceous understory of a forest floor can be largely influenced by the adjacent canopy tree species. We sampled 107 sites listed in the Continuing Forest Inventory database of the Stockbridge-Munsee forest. Seven canopy compositions were aggregated: red pine, white pine, white cedar swamp, eastern hemlock, eastern hemlock-hardwood mixture, northern hardwood, and second-growth disturbed. For each of these canopy types, we sampled average density of the herbaceous plants of the forest floor. We hypothesized that the herbaceous compositions should be markedly different among each canopy type. Significant differences (MANOVA, F=5.02, p < 0.001) existed among the herbaceous compositions. Northern hardwood herbaceous assemblages were the most diverse, while eastern hemlock assemblages were the least diverse. We applied discriminant analysis to classify each canopy type according to the understory vegetation. Cross-validation discrimination accurately classified only the eastern hemlock and northern hardwood canopies. However, resubstitution discrimination accurately classified 6 of the 7 canopy types, suggesting that our results may be beneficial towards describing a relationship within the herbaceous understory and the canopy species of the Stockbridge-Munsee forest.
KEY WORDS: herbaceous ground cover, forest canopy