| Family | Scientific Name | Common Name | Habitat | Distribution | Image |
|---|---|---|---|---|---|
| Alismataceae | Alisma | Water-plantain |  (c) Kosterin, Oleg - CC-BY | ||
| Alismataceae | Alisma gramineum | Grassleaf Water-plantain | In seasonally flooded areas in impoundments. | This species is circumboreal, ranging in North America south to e. Virginia, New York, Wisconsin, s. Missouri, New Mexico, and California. | (c) Kosterin, Oleg - CC-BY |
| Alismataceae | Alisma plantago-aquatica | ||||
| Alismataceae | Alisma subcordatum | Southern Water-plantain | Marshes, ponds, stream edges. | Massachusetts west to North Dakota, south to Georgia and Texas. |  (c) Sorrie, Bruce A. - CC-BY |
| Alismataceae | Alisma triviale | Northern Water-plantain | Marshes and swamps. | Newfoundland and Labrador (Newfoundland) west to Alaska, south to s. New Jersey, s. Pennsylvania, Ohio, Indiana, Arkansas, Oklahoma, New Mexico, Arizona, California, and n. Mexico (and according to Fernald to Maryland and West Virginia). Discovered in Kentucky Mountains by V. Voelker (pers.comm.). |  (c) Korol, J. Burke - CC-BY-NC, permission granted to NCBG |
| Alismataceae | Alismataceae | Water-plantain Family |  (c) Cressler, Alan M. | ||
| Alismataceae | Echinodorus | Burhead |  (c) Sorrie, Bruce A. - CC-BY | ||
| Alismataceae | Echinodorus berteroi | Tall Burhead, Upright Burhead | Ponds, marshes, ditches, typically in seasonally flooded situations. | Ohio, Illinois, and North Dakota south to e. Panhandle Florida, s. Florida, sw. Georgia, and Texas, south through Mexico; West Indies; South America. Reported for s. Florida (Lange, Bradley, & Sadle [in prep.]). |  (c) johnyochum - CC-BY |
| Alismataceae | Echinodorus cordifolius | Creeping Burhead | Swamps, ditches, wet thickets, especially on base-rich substrates, such as over calcareous or mafic rocks. | Maryland south to c. peninsular Florida, west to Texas, south into Mexico (Campeche, San Luis Potosí, Tamaulipas, Veracruz, Yucatán), South America, West Indies), and north in the interior (primarily in the Mississippi Embayment) to s. Illinois. |  (c) Fleming, Gary P. |
| Alismataceae | Echinodorus grandiflorus | Large Burhead | Swamps. | Native of South America. |  (c) Braun, Holger - CC-BY |
| Alismataceae | Helanthium | Dwarf-burhead |  (c) Marcum, Paul | ||
| Alismataceae | Helanthium tenellum | Mud-babies, Dwarf-burhead | On drawdown zones of Coastal Plain ponds, pineland ponds, pondcypress savannas in clay-based Carolina bays, blackwater riverbanks, or ponds in the Mountains with Coastal Plain affinities (Augusta County, VA); also apparently adventive on drawdown zones of artificial impoundments (Lake Chatuge, sw. NC and n. GA). | Massachusetts west to Michigan and Kansas, south to c. peninsular Florida and s. Texas, but widely scattered and disjunct in that range; also Mexico (Chiapas, Guerrero, Veracruz), Central America, South America; West Indies. See Belden et al. (2004) for a discussion of the species in Virginia. |  (c) Cressler, Alan M. |
| Alismataceae | Hydrocleys | Water-poppy |  (c) Tripaldi, Ariadna - CC-BY | ||
| Alismataceae | Hydrocleys nymphoides | Water-poppy | Ponds and canals; cultivated in aquaria and spread by throw-outs. | Native of Central and South America. |  (c) McCorquodale, David - CC-BY |
| Alismataceae | Sagittaria | Arrowhead, Katniss, Flecha de Agua |  (c) Ward, Scott G | ||
| Alismataceae | Sagittaria ambigua | Plains Arrowhead, Kansas Arrowhead | Pond and lake shores, ditches. | Indiana and w. Illinois west to Kansas, south to s. Missouri and e. Oklahoma. |  (c) Hoisington, Dana - CC-BY-NC |
| Alismataceae | Sagittaria australis | Appalachian Arrowhead, Longbeak Arrowhead | Marshes, swamps, rivershores, backwaters, margins of ponds and lakes. | New York west to s. Indiana and se. Missouri, south to South Carolina, Panhandle Florida, and Mississippi. |  (c) Hartley, Nate - CC-BY-NC, permission granted to NCBG |
| Alismataceae | Sagittaria brevirostra | Midwestern Arrowhead, Shortbeak Arrowhead | Shores, shallow water. | Ohio west to North Dakota, south to n. Virginia, e. Tennessee, Alabama, and Texas. |  (c) DeLong-Duhon, Sarah - CC-BY |
| Alismataceae | Sagittaria calycina | Hooded Arrowhead | Seasonally exposed shores and flats of ponds, pools, and impoundments. | N. Ohio and Michigan west to South Dakota and Colorado, south to sw. Virginia, c. Tennessee, Louisiana, Texas, and Mexico; disjunct in California. Scattered occurrences eastwards are difficult to interpret as to 'nativeness', being primarily or entirely in manmade wetlands, to which they may have arrived by a diversity of means. First reported for South Carolina by Hill & Horn (1997). |  (c) Fleming, Gary P. |
| Alismataceae | Sagittaria chapmanii | Chapman's Arrowhead | Limesink (doline) ponds with drawdown hydrology, mucky ditches. | E. North Carolina south to s. Florida, west to e. Louisiana. First reported for South Carolina by Nelson & Kely (1997). reports from west of the Mississippi River are based on misidentifications of S. platyphylla. |  (c) Bradley, Keith |
| Alismataceae | Sagittaria cuneata | Northern Arrowhead, Arumleaf Arrowhead, Wapato | Ponds, marshes, shores. | Nova Scotia west to Alaska, south to Connecticut, nw. New Jersey, nw. Pennsylvania, Indiana, Illinois, Iowa, Oklahoma, n. Texas, New Mexico, Arizona, and California. |  (c) Pogacnik, Shaun - CC-BY-NC, permission granted to NCBG |
| Alismataceae | Sagittaria engelmanniana | Blackwater Arrowhead, Engelmann's Arrowhead | Blackwater streambanks, sphagnum bogs, pocosins, beaver ponds. | New Hampshire (Standley et al. 2025), Massachusetts, and New York south to s. Florida and s. Alabama, primarily on the Coastal Plain (rarely disjunct inland). |  (c) Sorrie, Bruce A. - CC-BY |
| Alismataceae | Sagittaria fasciculata | Bunched Arrowhead | Bogs, ditches adjacent to drained bogs, wooded seepage areas. | Endemic to a several-county area in sw. North Carolina and nw. South Carolina, where most of its former habitat has been drained. |  (c) Cressler, Alan M. |
| Alismataceae | Sagittaria filiformis | Threadleaf Arrowhead | Swiftly flowing water of blackwater rivers and streams, blackwater lake shores, tidal waters. | As conceived here, probably ranging from Maine south to s. Florida, s. Alabama, and s. Mississippi. |  (c) Machado, Siddarth - CC-BY |
| Alismataceae | Sagittaria graminea | Grassleaf Arrowhead | Marshes, ponds, freshwater and oligohaline tidal marshes. | Newfoundland and Labrador (Newfoundland) and Newfoundland and Labrador (Labrador) west to Minnesota and South Dakota, south to s. Florida and c. Texas; West Indies. |  (c) Cressler, Alan M. |
| Alismataceae | Sagittaria guayanensis ssp. guayanensis | Guayana Arrowhead | Disturbed wetlands, rice fields. | Native of Mexico, Central America, South America, and the West Indies. | |
| Alismataceae | Sagittaria isoetiformis | Quillwort Arrowhead | Pineland ponds, clay-based Carolina bays, natural lake shoreline marshes, other seasonally flooded depressions. | Se. North Carolina south to s. peninsular Florida, west to s. Mississippi (Sorrie & Leonard 1999); w. Cuba (POWO 2024). | |
| Alismataceae | Sagittaria kurziana | Spring-tape | Spring-runs. | Panhandle and n. and c. peninsular Florida. | |
| Alismataceae | Sagittaria lancifolia var. lancifolia | Bulltongue Arrowhead, Langue du boeuf (frc) | Marshes, swamps. | E. South Carolina south to s. Florida, west to Florida Panhandle; West Indies; n. South America. Reports further west in the Gulf Coastal Plain (Mississippi and Louisiana) are unverified. | (c) Ward, Scott G |
| Alismataceae | Sagittaria lancifolia var. media | Scimitar Arrowhead | Freshwater to brackish (mesohaline) tidal marshes. | S. Delaware south to ne. Florida, Florida Panhandle, west to Texas; scattered in Central America and n. South America. |  (c) Sorrie, Bruce A. - CC-BY |
| Alismataceae | Sagittaria latifolia var. latifolia | Common Arrowhead, Broadleaf Arrowhead, Wapato, Duck-Potato | Marshes, swamps, farm ponds, ditches, bogs. | Nova Scotia west to British Columbia, south to tropical America (rare in the Appalachian region). |  (c) Fleming, Gary P. |
| Alismataceae | Sagittaria latifolia var. pubescens | Common Arrowhead, Broadleaf Arrowhead, Wapato, Duck-Potato | Bogs, marshes. | C. Pennsylvania, Ohio, and Tennessee, south to n. Florida and e. Louisiana, centered in the Appalachians. |  (c) Fleming, Gary P. |
| Alismataceae | Sagittaria longiloba | Long-lobe Arrowhead, Flecha de Agua | Swamps, ponds, ditches. | Nebraska, New Mexico, Arizona, and California south to s. Texas and Mexico; Nicaragua, Venezuela. | |
| Alismataceae | Sagittaria macrocarpa | Beaverponds, old millponds, sometimes under gum and maple canopy. | Apparently endemic to the Coastal Plain of the Carolinas; potentially to be expected in e. Georgia |  (c) Sorrie, Bruce A. - CC-BY | |
| Alismataceae | Sagittaria montevidensis | Giant Arrowhead | Disturbed areas, marshes. | Native of South America. Most of the collections from the southeastern United States are old collections around major seaports, suggesting that this plant was introduced on the ballast of sailing ships. |  (c) Marcum, Paul |
| Alismataceae | Sagittaria papillosa | Nipple-bract Arrowhead | Bogs, swamps, ditches, depressions. | C. Arkansas and se. Oklahoma south to s. Louisiana and c. Texas; rarely disjunct east of the Mississippi in se. Louisiana and s. Mississippi, and ec. North Carolina (Johnston County; P.D. McMillan, pers.comm., 2024). |  (c) Hill, Sonnia |
| Alismataceae | Sagittaria platyphylla | Delta Arrowhead | Marshes, ditches, farm ponds, pondcypress wetlands, canals. | Virginia, Ohio, Illinois, Missouri, and Oklahoma, south to Florida, Texas, and Mexico. The distribution of this species is primarily in the Mississippi drainage; occurrences east of the Appalachians may be introduced, either by humans or by waterfowl. First reported for Virginia by Wieboldt et al. (1998). Reported for c. Florida (Orange County) by Dalager (2022, who considers it as introduced there and likely via the aquatic plant industry. |  (c) Campos, Aidan |
| Alismataceae | Sagittaria rigida | Sessile-fruited Arrowhead, Stiff Arrowhead | Natural mountain ponds, wet meadows. | Maine, Québec, Minnesota, and Manitoba south to w. Virginia, nc. Tennessee, Missouri, nw. Arkansas, and Nebraska. |  (c) Danielson, Erik |
| Alismataceae | Sagittaria secundifolia | Little River Water-plantain, Kral's Arrowhead | Crevices in sandstone bedrock in streambeds. | Endemic to se. Tennessee, nw. Georgia, and nc. Alabama. Disjunct further south in ec. AL (Coosa County; Threlkeld 1427, see Keener et al. 2026 for specimen image). |  (c) Cressler, Alan M. |
| Alismataceae | Sagittaria spongiosa | Tidal Arrowhead | Tidal marshes and mud flats. | New Brunswick south to e. North Carolina along the coast. |  (c) Blaney, Sean - CC-BY-NC |
| Alismataceae | Sagittaria subulata | Dwarf Arrowhead, Awl-leaf Arrowhead | Tidal marshes and mud flats. | Massachusetts and New York south to n. peninsular Florida and Mississippi; allegedly also in n. South America (POWO 2024). |  (c) Radford, Ahles and Bell |
| Alismataceae | Sagittaria teres | Slender Arrowhead | Ponds. | Massachusetts south to s. New Jersey. |  (c) doug_mcgrady - CC-BY-NC |
| Alismataceae | Sagittaria weatherbiana | Weatherby’s Arrowhead | Fresh to brackish marshes, tidal cypress-gum swamps, streambanks, pineland pools. | Se. Virginia south to Panhandle Florida. |  (c) Fleming, Gary P. |