Lake Norman
Temp: 37.0F    Humidity: 93%    More Lake Norman Weather


Information about Lake Norman
  • About Lake Norman
  • The Law!
  • Water Temperature
  • Weather
  • Aquatic Plants
  • Birds / Waterfowl
  • Fishing
  • Lake Level
  • Map
  • Marine Commission

  • Photos and information from around Lake Norman
  • Boat Access Areas
  • Day Trips/Hiking Trails
  • Marinas
  • Swimming
  • Photo Gallery
  • Golf Courses
  • Webcams
  • Hospitals
  • Historical Sites
  • Churches
  • Airports
  • Real Estate
  • Car Dealers
  • Lake Norman Website Design

  • Photos and information about the towns around Lake Norman
  • Catawba, NC
  • Cornelius, NC
  • Davidson, NC
  • Denver, NC
  • Huntersville, NC
  • Mooresville, NC
  • Sherrills Ford, NC
  • Statesville, NC
  • Troutman, NC

  • Information about Lake Norman
  • Search
  • Advertise With Us
  • Our Customers
  • Domain Names For Sale
  • Terms of use and Legal Notice

  • Hydrilla

    Hydrilla verticillata

    Hydrilla is considered the most problematic aquatic plant in the United States.

    Hydrilla is a submersed plant. It can grow to the surface and form dense mats thick enough for ducks to walk on. It was first found in Lake Norman in 2000 and is spreading rapidly.

    Hydrilla stems are slender, branched and up to 25 feet long. Hydrilla's small leaves are strap-like and pointed. They grow in whorls of four to eight around the stem. The leaf margins are distinctly saw-toothed. Hydrilla often has one or more sharp teeth along the length of the leaf mid-rib. Hydrilla produces tiny white flowers on long stalks. It also produces 1/4 inch turions at the leaf axils and potato-like tubers attached to the roots in the mud.  There are several Hydrilla "look alkies".  There is more information about them near the bottom of this page.

    Why is Hydrilla a problem?

    • Makes swimming, boating, fishing, and water skiing difficult and dangerous - or impossible (people have drowned because of Hydrilla!).
    • Hinders commercial navigation
    • Clogs water intake systems
    • Shades out desirable aquatic plants
    • Provides breeding habitat for mosquitoes and other pest.

    How to Control Hydrilla

    Once Hydrilla becomes established, eradication is often not possible.  The treatment required to control infestations within levels that would permit continued use of lakes and streams is difficult and expensive. 

    Herbicides and mechanical harvesters provide some control of Hydrilla, but both are expensive and regrowth can be rapid requiring repeated treatments. NOTE: The Catawba Riverkeeper Foundation, Catawba Riverkeeper, and The Lake Norman Covekeepers DO NOT support herbicides as a control method!  

    Herbicides used on Hydrilla:
    • Glyphosate, (a suspected human carcinogen and mutagen)
    • Diquat, (known to cause liver damage and cataracts)
    • Copper, (known human mutagen with varying toxicity to fish) has also been found to damage aluminum boats and pontoons.
    • Fluridone. (moderate toxicity to fish and other aquatic organisms)

    The most cost-effective, long tern control of Hydrilla is the use of sterile grass carp, Ctenopharyngodon idella.  When this herbivorous fish is stocked at rates of up to 20 fish per acre of Hydrilla, control can generally be obtained in one or two years.  Once control is obtained, maintenance stockings of grass carp are required to maintain control in subsequent years.  Click here for more info about Grass Carp used to control the Hydrilla on Lake Norman.

    Whole-lake management of hydrilla with grass carp is certainly possible, however, the "getting there" will be exceedingly challenging.  An estimate of grass carp management costs of hydrilla on Lake Norman could easily be based on 160,000 fish (8000 potential hydrilla acres times 20 fish per acre) at $4.00 a fish. Supplemental stocking (~25% of the original stocking) would be required every two years or so to maintain a viable weed eating population of grass carp. Management of hydrilla is a long-term

    Following a time consuming hydrilla distribution assessment by Lake Norman's Duke Power's Mosquito Control Teams, hydrilla is now scattered over approximately 18 square miles of lake surface area.  This is an increase of 14 square miles from last year. The key word is scattered. It is not covering 18 square miles of lake surface. The plant is growing in individual scattered sprigs, small clumps to large clumps and complete cove coverage depending on the location. 

    The photo below shows the mosquito habitat and muck that can be created by Hydrilla (photo taken at Mountain Island Lake July 2002).

    Hydrilla look-alikes

    American waterweed = Canadian elodea = Elodea canadensis
    Native to the US

    Brazilian elodea = Egeria densa
    Non-Native to the US

    (Anacharis is a term used for all the above)

    Comparisons of the three (this page may load very slow)

    Links to Hydrilla information on other sites

    Hydrilla infestation at Lake James

    Duke Power answers Lake James Hydrilla questions

    Mountain Island Marine Commission Hydrilla information

    University of Florida - Hydrilla identification and photos


    Back to Aquatic plants



    Best Of Lake Norman .com is owned by McBryde Website Design
    148 River Park Road  |  Mooresville, NC 28117  |  Lake Norman
    Phone 704-660-7052  |  Fax 704-799-8528  |  
    E-mail Us
    Copyright 2018 McBryde Website Design  |   Legal Notice and Disclaimer  |   Privacy Policy