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Hydrilla

Scientific Name

Hydrilla verticillata (L. f.) Royle (ITIS)

Common Name

Hydrilla, Florida elodea, water thyme, Indian star-vine

Native To

Eastern Hemisphere; U.S. strains possibly originated in Asia (Balciunas et al. 2002)

Date of U.S. Introduction
Means of Introduction

Aquarium trade (Balciunas et al. 2002)

Impact

Crowds out native species; impedes irrigation and boating (Balciunas et al. 2002)

Hydrilla

Hydrilla, plants

Credit

Photo by Raghavan Charudattan; University of Florida

Find more images

Spotlights

  • First Michigan Detection of Invasive Hydrilla Triggers Response

    • Oct 2, 2023
    • Michigan.gov. Michigan Invasive Species Program.

    • Hydrilla, considered one of the world's most invasive aquatic plants, has been detected for the first time in Michigan. The Department of Environment, Great Lakes and Energy confirmed two small populations of the plant in adjacent private ponds on residential properties in Berrien Springs in Southwest Michigan.

      The small patches of hydrilla (Hydrilla verticillata) were discovered during routine monitoring following treatment for another invasive plant, parrot feather, which was found in the pond in 2020. Both species are prohibited in Michigan, meaning it is unlawful to sell, possess or import them into the state, and both are on Michigan’s invasive species watch list due to their potential environmental threat. Any suspicious aquatic plants should be reported as soon as possible to EGLE-WRD-AIP@Michigan.gov. Include close-up photos and provide the location of the detection in your report. More information on identifying and reporting invasive aquatic plants can be found at Michigan.gov/Invasives.

  • USACE Buffalo District Fights Invasive Hydrilla on the Great Lakes

    • Jan 9, 2020
    • DOD. USACE. Buffalo District.

    • The U.S. Army Corps of Engineers Buffalo District is on a mission to fight hydrilla, an aggressive plant species that has wreaked havoc from Asia to every continent except Antarctica. "Hydrilla completely chokes out our waterways and impacts all the things we enjoy,” said Michael Greer, USACE Buffalo District project manager." It affects water quality, the economy, businesses, hydropower and flood reduction - ultimately our health and our wallets." Buffalo District’s main projects to eradicate hydrilla are at the Erie Canal and Tonawanda Creek, Tonawanda, NY, as well as on Cayuga Lake near Aurora, NY and Ithaca, NY. The District provides assistance on Pymatuning Lake which borders Pennsylvania and Ohio, and at Raystown Lake in south central Pennsylvania. Buffalo District is also lending expertise to a project on the Connecticut River. Funding for the project is available through the Corps of Engineers Aquatic Plant Control Research Program and Great Lakes Restoration Initiative.

Distribution / Maps / Survey Status

Federally Regulated

  • Noxious Weeds Program

    • USDA. APHIS. Plant Protection and Quarantine.

    • Includes species listed as a Federal Noxious Weed under the Plant Protection Act, which makes it illegal in the U.S. to import or transport between States without a permit.

Videos

Selected Resources

The section below contains highly relevant resources for this species, organized by source.

Council or Task Force
Partnership
Federal Government
State and Local Government
Academic
Professional
Citations
  • Balciunas, J.K., M. J. Grodowitz, A.F. Cofrancesco and J.F. Shearer. 2002. Hydrilla. In: R. Van Driesche et al. (Eds.), Biological control of invasive plants in the eastern United States (FHTET-2002-04). Morgantown, West Virginia: U.S. Forest Service Forest Health Technology Enterprise Team.

  • Integrated Taxonomic Information System. Hydrilla verticillata. [Accessed Sep 16, 2023].