''Sagittaria filiformis'', the threadleaf arrowhead, is a perennial

aquatic plant Aquatic plants, also referred to as hydrophytes, are vascular plants and Non-vascular plant, non-vascular plants that have adapted to live in aquatic ecosystem, aquatic environments (marine ecosystem, saltwater or freshwater ecosystem, freshwater ...

growing up to tall. Some

leaves A leaf (: leaves) is a principal appendage of the stem of a vascular plant, usually borne laterally above ground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", while the leaves, stem, ...

are thread-like, entirely underwater, but others are narrowly ovate or lanceolate and floating on the surface. The species is native to the eastern

United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...

, from

Maine Maine ( ) is a U.S. state, state in the New England region of the United States, and the northeasternmost state in the Contiguous United States. It borders New Hampshire to the west, the Gulf of Maine to the southeast, and the Provinces and ...

south to

Florida Florida ( ; ) is a U.S. state, state in the Southeastern United States, Southeastern region of the United States. It borders the Gulf of Mexico to the west, Alabama to the northwest, Georgia (U.S. state), Georgia to the north, the Atlantic ...

and

Alabama Alabama ( ) is a U.S. state, state in the Southeastern United States, Southeastern and Deep South, Deep Southern regions of the United States. It borders Tennessee to the north, Georgia (U.S. state), Georgia to the east, Florida and the Gu ...

. It occurs in flowing streams in the northern part of its range, but more stagnant waters such as marshes and swamps in the South.

References

External links

photo of herbarium specimen at Missouri Botanical Garden, holotype of ''Sagittaria filiformis'', collected in Alabamaphoto of herbarium specimen at Missouri Botanical Garden, ''Sagittaria filiformis'', collected in FloridaCenter for Aquatic and Invasive Plants, University of FloridaGo Botany, New England Wildflower Society
{{Taxonbar, from=Q15572318 filiformis Flora of the Eastern United States Freshwater plants Plants described in 1894