Aquatic plant regulations
Under Minnesota law, aquatic plants growing in public waters are the property of the state. Because of their value to the lake ecosystem, they may not be destroyed or transplanted unless authorized by the Commissioner of the Department of Natural Resources as stipulated in the Aquatic Plant Management Rules. (A "public water" is generally any body of water 2.5 acres or larger within an incorporated city limit, or 10 acres or larger in rural areas. If you are unsure whether a particular lake is public, please contact your local DNR office.)
Activities NOT allowed:
Control methods which MUST HAVE a permit
- Destruction of any emergent vegetation (for example, cattails and bulrushes).
- Cutting or pulling by hand, or by mechanical means, submerged vegetation in an area larger than 2,500 square feet.
- Applying herbicides or algicides.
- Moving or removing a bog of any size that is free-floating or lodged in any area other than its place of origin in public waters.
- Transplanting aquatic plants into public waters.
- Use of automated aquatic plant control devices (such as the Crary WeedRoller).
- Physical removal of floating-leaf vegetation from an area larger than a channel 15 feet wide extending to open water.
When a permit is NOT needed
If you are a lakeshore-property owner who wants to create or maintain a swimming or boat-docking area, you may cut or pull submerged vegetation, such as Elodea, without a DNR permit under certain conditions:
- First, the area to be cleared must be no larger than 2,500 square feet.
- Second, the cleared area must not extend more than 50 feet along the shoreline or one-half the length of your shoreline, whichever is less.
A boat channel up to 15 feet wide, and as long as necessary to reach open water, may also be cleared, through submerged vegetation. (The boat channel is in addition to the 2,500 square feet allowed). The cutting or pulling may be done by hand or with hand-operated or powered equipment that does not significantly alter the course, current, or cross-section of the lake bottom. Such control cannot be done with draglines, bulldozers, hydraulic jets, suction dredges, automated aquatic plant control devices, or other powered earth-moving equipment. After you have cut or pulled aquatic plants, you must dispose of them on land to prevent them from drifting onto your neighbor's property or washing back into the lake. In addition, a channel 15 feet wide through floating-leaf vegetation extending to open water may be maintained by mechanical means without a permit. Any other destruction of floating-leaf vegetation requires a permit. If you have questions on control activities that do not require a permit, please contact your local DNR office.
A DNR permit is not needed to gather aquatic plants for personal use (except for wild rice) or for constructing a shooting or observation blind.
Applying for a permit
To apply for a permit, contact the Aquatic Plant Management Program or the closest regional office. The DNR does not grant permits automatically. Site inspections are required for first time permits. Applications may be denied or modified. To ensure that plant control is done correctly and with proper care for the environment, take these three steps:
- If herbicides are permitted carefully read the product label and follow all instructions.
- Notify the DNR before control operations begin, as specified on the permit.
- Post signs that identify the area that will be treated with an herbicide. These signs are included with the permit or are furnished by the DNR to the commercial applicator. There may be water use restrictions required on the product label for swimming, fish consumption, irrigation, or household use until the herbicide is broken down or has been diluted to safe levels. You will be asked to report the actual size of the controlled area and the amount of chemical used. This will help the DNR monitor statewide use of aquatic herbicides in public waters.
If you are inexperienced or uncomfortable applying herbicides, you may want to hire a licensed pesticide applicator . These applicators will frequently help you obtain a permit as part of their services. There are also companies that will mechanically harvest aquatic plants for hire.
Permit to Control Aquatic Plants, Algae, Swimmer's Itch, and Leeches
Application to Collect and/or Transplant Aquatic Vegetation
Costs, liability, and other information
In addition to administering permits, the DNR evaluates plant-control methods and provides guidance to lake associations. The agency does not endorse specific herbicides, products, or companies. Nor does the DNR arbitrate the results of control work. Liability for damage resulting from control work rests with the permittee (person receiving the permit) or his or her agent. Costs of aquatic plant-control projects are paid by the property owners who benefit from the control. An exception is the control of exotic plants such as Eurasian watermilfoil, where state funding may be available. In addition, Minnesota Statutes, Section 103G.621 authorizes cities and towns to levy taxes for the control of aquatic plants.