Rediscoveries of Dichanthelium scoparium (Poaceae) in Southern New England and Evaluation of Past Records from New England and New York

ABSTRACT. Dichanthelium scoparium (Poaceae) is a robust, rhizomatous panic-grass of the eastern United States. Most common in the southeast, it is considered rare in New York and had not been observed in New England since 1931. In recent years, we have discovered four new populations in Massachusetts and Rhode Island, reestablishing the species as extant in New England. To establish context for these discoveries, we evaluated past records from New England and New York, principally by inspecting digital images of voucher specimens, relying on the readily discernible diagnostic characters of the species. Using the subset of 22 verified records, we elucidate the regional distribution of the species and discuss patterns of habitat and ecological processes that may affect its presence and persistence on the landscape.