The Blackwater Ecologic Preserve includes the northernmost stand of Pinus palustris in the United States as well as several associated species unique in Virginia. The following two relict pyrophytic communities are recognized: Pinus palustris/Quercus laevis/mixed ericads on a sand ridge and Pinus serotina/Pinus serotina–Quercus laevis/mixed ericads or Pyxidanthera barbulata on a moist sand flat. Other communities include a mixed oak-pine slope, a black gum swamp, a river bluff, and an alluvial flat. Vegetation analyses of each community are presented. The history of botanical exploration, presettlement vegetation of the area, and importance of Pinus palustris in Virginia are discussed.