Vascular plant communities in six Carolina bays in Maryland were classified using stratified-random plot sampling of presence and cover in conjunction with Bray-Curtis Polar Ordination and Sorensen’s Index of Dissimilarity. Species diversity and annual cover differences also were analyzed during the two-year study period of 1987-1988. Collectively, five zonal community types were identified in the ground layer. The most frequent type, dominated by <em>Leucothoe racemosa</em> Gray, was restricted to the forested perimeter. The <em>Carex walteriana</em> Bailey (C. striata Michx.) community occurred as an interlying zone near or contiguous with the forested perimeter and as the sole non-perimeter community. <em>Panicum hemitomon</em> Schult. only occurred as a narrow band near or adjacent to the forested perimeter. <em>Rhexia virginica</em> L. and <em>P. verrucosum</em> Muhl. communities were restricted to the innermost non-perimeter zone. Species diversity and annual differences in cover generally increased from perimeter to center. <em>Leucothoe racemosa</em>, <em>P. hemitomon</em>, and <em>C. walteriana</em> communities, restricted to drier portions of the gradient, had lower values for these parameters than the more mesic <em>R. virginica</em> and <em>P. verrucosum</em> communities.