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Species
Salvinia molesta D. S. Mitchell
IUCN
NCBI
EOL Text
Plants free-floating aquatics. Rhizome up to 1.2 mm in diameter, horizontal, repeatedly dichotomously branched, with brown hairs. Leaves in whorls of three, two unwettable floating leaves and a submerged leaf at each node. Floating leaves broadly obovate, rounded to emarginate at the apex, cordate at the base, folded along the midrib in vigorous plants; upper surface covered with parallel rows of multicellular stalked hairs each subtended by 3-4 arms which re-unite at the apex in a cagelike structure, lower surface only simple hairs near the midrib. Submerged leaf finely dissected, rootlike, up to 12 cm long, set with brown hairs. Sporocarps in 2 rows along one lobe of the submerged leaf, ovoid, c. 2-3 mm in diameter, resembling a string of beads, heterosporous.
Giant salvinia poses a serious threat to lakes, ponds, streams, rivers and other freshwater wetlands, and cultivated rice fields. It grows rapidly and spreads across water surfaces, forming dense floating mats that cut off light to other aquatic plants, reduce oxygen content and degrade water quality for fish and other aquatic organisms.
License | http://creativecommons.org/licenses/by-nc-sa/3.0/ |
Rights holder/Author | U.S. National Park Service |
Source | http://www.nps.gov/plants/alien/pubs/midatlantic/samo.htm |
molesta: annoying, troublesome; a reference to the difficulties in eradicating the spreading nature of this plant in aquatic habits such as Lake Kariba along the Zambezi River. The popular name is, therefore, 'Kariba Weed'.
Comments: Considered exotic in North America (23 Mar 94)
License | http://creativecommons.org/licenses/by-nc/3.0/ |
Rights holder/Author | NatureServe |
Source | http://explorer.natureserve.org/servlet/NatureServe?searchName=Salvinia+molesta |
Introduced from tropical America to southern, central and east Africa; also naturalised on Mauritius & Rodrigues Island, India, Sri Lanka, Australia and possibly Malaysia, Indonesia and New Zealand.
United States
Origin: Exotic
Regularity: Regularly occurring
Currently: Unknown/Undetermined
Confidence: Confident
License | http://creativecommons.org/licenses/by-nc/3.0/ |
Rights holder/Author | NatureServe |
Source | http://explorer.natureserve.org/servlet/NatureServe?searchName=Salvinia+molesta |
Global Range: Escaped as an exotic in the U.S. in Texas, Louisiana, Alabama, Florida (Kartesz 1999), and Georgia (Georgia Natural Heritage Program, July 2000).
License | http://creativecommons.org/licenses/by-nc/3.0/ |
Rights holder/Author | NatureServe |
Source | http://explorer.natureserve.org/servlet/NatureServe?searchName=Salvinia+molesta |
Giant salvinia has populations scattered throughout the southeastern U.S. from eastern Texas through eastern North Carolina. There are two known occurrences in the tip of southern California. In the summer of 2000, a small population was discovered in ornamental ponds in Washington, D.C. but was quickly eradicated.
License | http://creativecommons.org/licenses/by-nc-sa/3.0/ |
Rights holder/Author | U.S. National Park Service |
Source | http://www.nps.gov/plants/alien/pubs/midatlantic/samo.htm |
South America
License | http://creativecommons.org/licenses/by-nc-sa/3.0/ |
Rights holder/Author | U.S. National Park Service |
Source | http://www.nps.gov/plants/alien/pubs/midatlantic/samo.htm |
- Plant: floating aquatic fern with leaves that become compressed into chains in older plants.
- Leaves: about ½-1½ inches long; oval, folded, and covered with arching hairs that appear like “beaters” on upper leaf surfaces.
- Flowers, fruits and seeds: reproduces and spreads by tiny spores (rather than flowers).
- Spreads: by transport of plant fragments by water, humans and wildlife.
- Look-alikes: common salvinia (Salvinia minima), a native plant, looks very similar, but its leaf hairs do not join at the tip to form “beaters.”
License | http://creativecommons.org/licenses/by-nc-sa/3.0/ |
Rights holder/Author | U.S. National Park Service |
Source | http://www.nps.gov/plants/alien/pubs/midatlantic/samo.htm |