This weed, called giant salvinia, is an exotic fern from South America that invades ponds, lakes, and other waterways in the United States. It damages aquatic ecosystems by outgrowing and replacing native plants that provide food and habitat for native animals and waterfowl.

Salvinia molesta, commonly known as giant salvinia, or as kariba weed after it infested a large portion of Lake Kariba between Zimbabwe and Zambia, is an aquatic fern, native to south-eastern Brazil. [1]

Giant salvinia (Salvinia molesta), a floating fern from southern Brazil, is currently one of the most problematic aquatic plants in Texas. It damages aquatic ecosystems by outgrowing and replacing native plants that provide food and habitat for native animals and waterfowl.

According to GISD (2018) Salvinia molesta has been nominated as among 100 of the "World's Worst" invaders. “Plants...up to 30 cm long, 5 cm wide, mat-forming, mat to 2.5 cm thick (or much thicker, depending on local conditions such as water current, waves, etc.).”

Noxious: This species is listed by the U.S. Department of Agriculture as a noxious weed. Identification: Free floating, aquatic fern. Consists of horizontal stems that float just below the water surface, and produce a whorl of three leaves (technically fronds) at each node.

2024年12月3日 · Considered in of the top most invasive aquatic plants worldwide, Giant salvinia readily colonizes disturbed habitats including rice paddies, flood canals, artificial lakes and hydro-electric facilities as well as natural waterways such as swamps, lakes, and rivers.

Giant salvinia, Salvinia molesta D. S. Mitchell (Salviniaceae), is an invasive free-floating fern native to southeastern Brazil that has plagued waterways of tropical and subtropical regions of the world.

Learn more about How to Control Giant Salvinia. View plant photos, descriptions, maps, treatment options, and more.

But the difference is that the trichomes of giant salvinia are closed at the tips and resemble an “egg-beater”, whereas the trichomes on common salvinia are branched and look like fingers. For more information, please see this video about giant versus common salvinia identification.

Giant salvinia is an aquatic fern prohibited in the United States by Federal law. Oblong floating leaves, 1/2 to 1 1/2 inches long. Young plants have smaller leaves that lie flat on the water surface.