Also called Esthwaite waterweed and waterthyme.

Native to 🇪🇺 Europe, Asia, Africa and 🇦🇺 Australia.  Invasive > learn+quiz Invasive > Global Invasive > in USA+Canada Invasive > report it! Invasive > in USA Invasive > in Michigan

For kids!  This plant described in invasive species placemat (.pdf) series

Learn more about hydrilla Hydrilla verticillata

Biological Control in Eastern USA (.pdf page 99)

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