Knowledge Bank

We classified plant communities by criteria of physiognomy, environment, and flora. Use of Mueller-Dombois and Ellenberg's classification scheme for the world's vegetation provided 6 vegetation categories. The results of a Bray-Curtis ordination were consistent with our field observation of a correlation between these vegetation categories and a soil moisture gradient. The results of a cluster analysis were consistent with 5 of the vegetation categories, but the sixth should be subdivided according to variations in floristic composition. Our proposed classification has 8 plant communities: an alluvial forest dominated by Acer negundo and Parthenocissus quinquefolia, a reed swamp dominated by Eupatorium perfoliatum and Typha latifolia, a deciduous thicket dominated by Crataegus punctata, a second deciduous thicket dominated by Cornus obliqua and Aster pilosus, and a third deciduous thicket dominated by Rosa palustris and R. setigera, a perennial forb community dominated by Clematis virginiana and Verbesina alternifolia, a tall-sedge swamp dominated by Carex stricta and Eupatorium maculatum, and a herbaceous floating meadow dominated by Typha latifolia and Eupatorium perfoliatum. We list 183 species (of 61 families) and state the communities in which each is common.