Aquatic Plants

Aquatic plants — also called hydrophytic plants or hydrophytes — are plants that have adapted to living in or on aquatic environments. Aquatic vascular plants can be ferns or angiosperms (from a variety of families, including among the monocots and dicots). Seaweeds are not vascular plants but multicellular marine algae. The following species have been reported to be invasive in natural areas in the U.S. Species native to the U.S. are included when they are invasive in areas well outside their known natural ranges, as a result of human activities. For more information on each species, including the listing sources, images, and distribution maps, click on the species.

38 Species

Subject Name Scientific Name Family U.S. Nativity
alligatorweed Alternanthera philoxeroides (Mart.) Griseb. Amaranthaceae Exotic
giant salvinia Salvinia molesta D. S. Mitchell Salviniaceae Exotic
Brazilian waterweed Egeria densa Planch. Hydrocharitaceae Exotic
common water hyacinth Eichhornia crassipes (Mart.) Solms Pontederiaceae Exotic
hydrilla Hydrilla verticillata (L. f.) Royle Hydrocharitaceae Exotic
purple loosestrife Lythrum salicaria L. Lythraceae Exotic
parrotfeather Myriophyllum aquaticum (Vell.) Verdc. Haloragaceae Exotic
Eurasian water-milfoil Myriophyllum spicatum L. Haloragaceae Exotic
brittleleaf naiad Najas minor All. Najadaceae Exotic
torpedograss Panicum repens L. Poaceae Exotic
common reed Phragmites australis (Cavanilles) Trinius ex Steudel Poaceae Exotic
water lettuce Pistia stratiotes L. Araceae Native
European water chestnut Trapa natans L. Trapaceae Exotic
water fern Salvinia minima Baker Salviniaceae Exotic
sessile joyweed Alternanthera sessilis (L.) R. Br. ex DC. Amaranthaceae Exotic
miramar weed Hygrophila polysperma (Roxb.) T. Anders. Acanthaceae Exotic
Mediterranean clone of caulerpa Caulerpa taxifolia (Vahl) C. Agardth Caulerpaceae Exotic
flowering-rush Butomus umbellatus L. Butomaceae Exotic
Carolina fanwort Cabomba caroliniana A. Gray Cabombaceae Native
swamp morningglory Ipomoea aquatica Forssk. Convolvulaceae Exotic
yellow iris Iris pseudacorus L. Iridaceae Exotic
creeping waterprimrose Ludwigia peploides (Kunth) Raven Onagraceae Native
reed canarygrass Phalaris arundinacea L. Poaceae Exotic
curly-leaved pondweed Potamogeton crispus L. Potamogetonaceae Exotic
deeprooted sedge Cyperus entrerianus Boeckl. Cyperaceae Exotic
European waterstarwort Callitriche stagnalis Scop. Callitrichaceae Exotic
giant chickweed Myosoton aquaticum (L.) Moench Caryophyllaceae Exotic
crested floating heart Nymphoides cristata (Roxb.) O. Ktze. Menyanthaceae Exotic
European frog-bit Hydrocharis morsus-ranae L. Hydrocharitaceae Exotic
European water-clover Marsilea quadrifolia L. Marsileaceae Exotic
yellow floating heart Nymphoides peltata (S.G. Gmel.) Kuntze Menyanthaceae Exotic
Asian kelp Undaria pinnatifida (Harvey) Suringar Alariaceae Exotic
common duckweed Lemna minor L. Lemnaceae Native
amphibious yellowcress Rorippa amphibia (L.) Besser Brassicaceae Exotic
watercress Nasturtium officinale R. Brown Brassicaceae Exotic
roundleaf toothcup Rotala rotundifolia (Buch.-Ham. ex Roxb.) Koehne Lythraceae Exotic
Cuban bulrush Oxycaryum cubense (Poepp. & Kunth) Lye Cyperaceae Native
dotted duckmeat Landoltia punctata (G.F.W. Mey.) D.H. Les & D.J. Crawford Lemnaceae Native