Trapa natans L.

Locations ofTrapa natans L. in Virginia

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Botanical Name
Trapa natans L.
Common Name
Chinese Water-chestnut, European Water-chestnut, Water-caltrop
Flora of Virginia Name/Status
Trapa natans L.
Now essentially gone from the Potomac River where once frequent and the target of intensive eradication efforts. Reported from Fairfax Co. at Gunston Cove [McAtee (1930), 7th Supplement to the Flora of D.C. and Vicinity]. The listing from Virginia Beach by Massey (1961) has not been substantiated. Plants thought to be Trapa natans were found in a few industrial ponds in Fairfax County beginning in 2006 but these more likely represent T. bispinosa, a recently discovered, cryptic invader (Chorak et al. 2019. Cryptic introduction of water chestunt (Trapa) in the northeastern United States. Aquatic Botany 155: 32-37.)
Potomac River and tributaries, at least formerly. Once rare in the n. Coastal Plain but not confirmed since ca. 1950s (Nancy Rybicki USGS aquatic plant ecologist, pers. comm.)
Native Status

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