Also called kariba weed.  An ♒︎ aquatic fern, part of watermoss  genus Salvinia and family Salviniaceae.

Native to southeastern Brazil.  Invasive > Global Invasive > in USA+Canada Invasive > report it! Invasive > in USA Invasive > in Michigan

Learn more about giant salvinia Salvinia molesta

Biological Control in Eastern USA (.pdf page 25)

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