Ludwigia palustris

L. palustris forms prostrate, sprawling mats in wet, disturbed areas. Its stems are semi-succulent, reddish in color, and smooth or slightly hairy. As the stems spread along the ground, roots form from the nodes. At maturity, the stems may reach 10-40 cm long. The leaves are opposite, smooth, oval-shaped, and reach up to 4 cm long. They have a winged petiole and are often reddish-green in color. The greenish-white flowers are born on the leaf axils and reach 2-3 cm long. == Taxonomy ==

Ludwigia palustris was given the scientific name Isnardia palustris in 1753 by Carl Linnaeus. It was moved to the genus Ludwigia by Stephen Elliott in 1817. Together with its genus it is classified in the family Onagraceae. Though it has not accepted varieties, there are five variety names among its 21 synonyms. == Distribution and habitat ==

L. palustris is circumpolar species with a large native range. It occurs in North America, South America, Africa, Asia, and Europe. It occurs as a naturalized or invasive species in Hawaii, Australia, and New Zealand. The species is generally restricted to low elevations, where it grows on shallow bodies of water such as reservoirs, ditches, and the banks of ponds, rivers, and streams. It requires wet, muddy or sandy soils poor in calcium but rich in humus and nutrients. == Conservation status ==

L. palustris is designated by the IUCN Red List and NatureServe as a secure (G5) species globally. In North America, it is also designated as secure (N5) in both Canada and the United States. In some states and provinces, it is designated to be at higher risk. In both Arizona and Prince Edward Island, it is ranked as a critically imperiled (S1) species. In New Mexico it is imperiled (S2). In Kansas, Iowa, and Quebec it is vulnerable (S3). The plant can be highly invasive outside its native range, very adaptable, and reproduces asexually. Ludwigia palustris poses a potential threat to wetland vegetation in Victoria, Australia. It has spread to riverbanks in Northeastern Australia and other areas. == Cultivation ==

L. palustris is cultivated for use in aquariums and aquascaping. It is often sold under the names Ludwigia 'super red', Ludwigia 'mini super red', or Ludwigia 'red'. ==References==