Cabomba caroliniana

History of Spread

Cabomba caroliniana (Carolina Fanwort) is native to sluggish streams and ponds in the southeastern United States. The original northern limits of its range are variously given as VA (Fernald 1950; Les and Mehroff 1999) or NJ (Gleason and Cronquist 1991), extending west to OH and south to FL and TX. Its distribution in VA and northern NC is spotty, with records in one northern NC Coastal Plain county, Suffolk and New Kent counties in the Elizabeth and James River County, and a cluster of records in the counties surrounding Washington DC (Arlington, Fairfax, Prince William, Stafford) (Natural Resources Conservation Service 2001). Further south, in NC, its distribution is more continuous. This plant's history in the Washington area is consistent with introduction (see below). Further north, the plant has been reported from MD (Brown and Brown 1984, no information on locations).

Cabomba carolina has been widely utilized as a water garden and aquarium plant, and is widely escaped in New England as far north as southeastern NH (Les and Mehrhoff 1999), and on the Pacific Coast in OR and WA (Natural Resources Conservation Service 2001). It was established in MA as early as 1920, where it survives the winter under ice, and reached NH by 1956 (Les and Mehrhoff 1999). It has been reported in estuarine waters in the Hamilton Marshes NJ (Delaware River estuary) (Leck et al. 1987) in tidal fresh marshes in the Merrimack River (Caldwell and Crow 1992), and side channels of the Columbia River estuary (Washington Department of Ecology 2001). Cabomba caroliniana has been introduced to Japan, India, Malaysia, and New Guinea (Washington Department of Ecology 2001).

In the Chesapeake Bay region, C. caroliniana has been reported from Suffolk and New Kent Counties (Natural Resources Conservation Service 2001), but with no habitat or history information available. In the Washington DC area, the earliest herbarium records are associated with the United States Fish Commission ponds, which were planted with ornamental and 'oxygenator' plants (Hitchcock and Standley 1919). This plant was first collected from a 'fish pond' in 1879, and was puzzlingly labeled 'introduced from the Patapsco River'. Specimens were collected from 'fish ponds' in Washington in 1904. In 1899, C. caroliniana was collected from tidal Dyke Marsh, Alexandria VA, and taken near Mount Vernon, on tidal Dogue Creek ('sea-level, prostrate on mud') in 1939 (U.S. National Herbarium collections). Elaine Haug (US National Museum of Natural History) has collected it in Dyke Marsh within the last 10 years (Haug 2001). However, this plant seems to be extremely rare in the tidal Potomac, and has not been reported in submerged aquatic vegetation (SAV) surveys.

References- Brown and Brown 1984; Caldwell and Crow 1992; Haug 2001 personal communication; Fernald 1950; Gleason and Cronquist 1991; Hitchcock and Standley 1919; Leck et al. 1987; Les and Mehrhoff 1999; U.S. National Herbarium collections; Washington Department of Ecology 2001

Invasion Comments