ABSTRACT
The vascular flora of Rock Creek Park, Washington, D.C., was surveyed from 1986 through 1994. The park is a forested steep valley in the eastern deciduous forest ecosystem, with 85% of its 1754 acres in natural forest. A total of 656 species representing 374 genera and 106 families were documented. Of these, 418 species are indigenous and 238 are introduced. Voucher specimens were deposited in the United States National Herbarium in The District of Columbia and Vicinity collection. In addition to providing a list of plants currently in the Park, this collection will contribute to the checklist of the Flora of Washington, D.C. and Vicinity, in progress at the Smithsonian Institution. Prior to this study, the last period of intensive collecting within Washington, D.C. was approximately 100 years ago.