Managing Nuisance Aquatic Plants





Invasive aquatic plants such as hydrillawater hyacinth and Eurasian watermilfoil are sometimes found in the Highland Lakes.

LCRA manages hydrilla and water hyacinth on the Highland Lakes when these plants have the potential to impact LCRA operations. If you see hydrilla or water hyacinth in the Highland Lakes, please contact LCRA Water Quality at [email protected].

Native plants cabombacoontail and water stargrass also can become abundant in the Highland Lakes and Colorado River. Treatment is not recommended for these native plants, as they provide important habitat for fish and other aquatic organisms.

Nuisance aquatic vegetation control options

The Texas A&M Agrilife Extension AquaPlant diagnostics tool provides guidance for plant identification and plant specific management. The tool also offers a list of professional applicators.

If you are planning to manually or chemically control any native or invasive plants that grow in public waterways, submit the following to the Texas Parks & Wildlife Department (TPWD) Inland Fisheries Management District Supervisor Patrick Ireland at [email protected] and LCRA at [email protected]:

  1. Treatment proposal form(Appendix C of the TPWD aquatic vegetation management guidance document) (.pdf)
  2. Map of the proposed treatment area
  3. Photographs of the plant and the problem it is causing

More information on the treatment proposal process can be found on the TPWD Nuisance Aquatic Vegetation website.

Do not proceed without TPWD approval.

If using an herbicide, suggested active ingredients are Bispyribac, Copper, Diquat, Endothall, Flumioxazin, Fluridone, Imazamox, and Florpyrauxifen-benzyl: 2-pyridinecarbolic acid, 4-amino-3-chloro-6-(4-chloro-2-fluoro-3-methoxy-phenyl)-5-fluoro-, phenyl methyl ester. Depending on the chemical used, lake water in the vicinity of the treatment should not be used for irrigation, livestock consumption, or potable purposes for certain periods after treatment. See the product label and Section III.C.3. of the TPWD aquatic vegetation management guidance document for more information.

If you have questions about treating native or nuisance vegetation on Lake Austin or Lady Bird Lake, contact the City of Austin Watershed Protection Department.

Help minimize growth and spread of invasive plants

    • Clean, drain and dry your boats when entering or leaving a lake to avoid transporting non-native species. Leaving a public water body without removing plants and draining all water from your boat and trailer is illegal.
    • Reduce or eliminate fertilization on lakeside properties.
    • Plant native vegetation buffer strips along the lakeshore to filter the nutrients from rainfall or irrigation runoff coming from lawns.
    • Don’t let grass clippings and leaves get into the lake.
    • Clean up pet waste.
    • Make sure septic systems are properly maintained to prevent excess nutrients from leaching into waterways that plants can use to grow.

If you have questions about nuisance aquatic vegetation, please contact TPWD at [email protected] or LCRA Water Quality at [email protected].