Wisconsin's Aquatic Plant Management and Protection Program
The role that trees play in a forest is much like the role of aquatic plants in a lake. We have become aware of the consequences of poor logging practices on the inhabitants of the forest ecosystem. We need to recognize that poor or irresponsible activities designed to control aquatic plants may have unanticipated and adverse effects on all the creatures that need and use the lake ecosystem... including us. Aquatic plants are the very foundation of a healthy lake ecosystem.
In order to protect diverse and stable communities of native aquatic plants and prevent the spread of invasive aquatic plants, many aquatic plant management and nuisance control activities require a permit issued by the Department. Please read the specific exceptions below and/or contact your local aquatic plant management coordinator before engaging in any aquatic plant management or nuisance control activities.
Aquatic plants form the foundation of healthy and flourishing lake ecosystems - both within lakes and rivers and on the shores around them. They not only protect water quality, but they also produce life-giving oxygen. Aquatic plants are a lake's own filtering system, helping to clarify the water by absorbing nutrients like phosphorus and nitrogen that could stimulate algal blooms. Plant beds stabilize soft lake and river bottoms and reduce shoreline erosion by reducing the effect of waves and current. Healthy native aquatic plant communities help prevent the establishment of invasive non-native plants like Eurasian watermilfoil.
It makes sense that the best fishing spots are typically near aquatic plant beds. Aquatic plants provide important reproductive, food, and cover habitat for fish, invertebrates, and wildlife. It's aquatic plants that fashion a nursery for all sorts of creatures ranging from birds to beaver to bass to bugs. In order to maintain healthy lakes and rivers, we must maintain healthy native aquatic plant communities.
In general, there are four ways to control or remove aquatic plants:
1. Chemical: includes herbicides and some dyes. Only those chemicals registered with the U.S. EPA (Exit DNR) and Wisconsin's Department of Agriculture, Trade, and Consumer Protection (Exit DNR) (DATCP) may be used. When controlling aquatic plants with chemicals, it is important to correctly identify the plants and the appropriate chemical beforehand and to be certain that treatment occurs at the proper timing and dosage. In order to apply chemicals in liquid form, the applicator must be licensed with the State. Therefore, Department staff often recommend that people contract a commercial applicator. Chemical control of aquatic plants always requires a permit.
2. Manual/Mechanical: includes hand-pulling and raking or mechanically harvesting plants. The regulation of mechanical and manual control of aquatic plants is new in Wisconsin. The Department may require an Aquatic Plant Management Plan before it issues a permit for these control methods. Mechanical control always requires a permit; manual control may require a permit.
3. Physical: includes bottom plant barriers and water drawdown. These methods are used only in special circumstances. Because they involve placing structure on the bed of a lake and/or affect lake water level, a Chapter 30 or 31 permit will most likely be needed.
4. Biological: includes herbivores and bacteria. Currently the most common biological control is the Galerucella beetle, which is used to control the invasive plant Purple Loosestrife (See picture below). It is illegal to transport or stock carp or crayfish in Wisconsin. Biological control of aquatic plants always requires a permit.
The Department protects native aquatic plants and regulates the control and removal of them:
Historically the Department required a permit only when chemicals were used to control aquatic plants as described in Administrative Rule NR 107(Exit DNR, PDF 24KB) - Aquatic Plant Management or when physical control involved methods (e.g. drawdown or a plant barrier) regulated by Wisconsin Statutes, Chapter 30, "Navigable Waters, Harbors and Navigation" (Exit DNR, PDF).
- Any time that chemicals, biological controls, and physical techniques (e.g. drawdown or bottom plant barrier) are used; or when wild rice is involved; and
- when plants are removed mechanically or manually from an area greater than 30 feet in width along the shore.
As of September 2001, however, the legislature passed a bill to further protect Wisconsin’s invaluable aquatic plant communities. The result is NR 109 (Exit DNR PDF, 19KB) - Aquatic Plants: Introduction, Manual Removal and Mechanical Control Regulations and regulates mechanical and manual control of aquatic plants. Additionally, it is illegal to transport boats or boating equipment that has aquatic plants or zebra mussels attached, and introductions of aquatic plants for planting require a permit.
In most instances, control of native aquatic plants is discouraged or should be limited to high use recreational areas that are next to piers and docks or within navigational channels. In some cases there may be penalties for improper removal of aquatic plants.
Any person who controls aquatic plants with chemicals must apply for a Chemical Control of Aquatic Plants Permit from the Department (Form 3200-4). Any person or organization (e.g. a municipality, lake association, or lake district) that controls aquatic plants mechanically or manually in an area greater than 30 feet in width along the shoreline must apply for a Mechanical/Manual Aquatic Plant Control Permit (Form 3200-113) from the Department. If a person or organization intends to control aquatic plants using alternative techniques such as water drawdown, a plant barrier, or biological controls, an alternative permit such as a Wisconsin Statutes, Chapter 30, "Navigable Waters, Harbors and Navigation" (Exit DNR, PDF) may be necessary.
The only time a permit is not required to control aquatic plants is when a riparian manually removes (i.e. hand-pulls or rakes), or gives permission to someone to manually remove, plants (except wild rice)from his/her shoreline in an area that is 30 feet or less in width along the shore and is not within a Designated Sensitive Area. The non-native invasive plants (Eurasian watermilfoil, curleyleaf pondweed, and purple loosestrife) may be manually removed beyond 30 feet without a permit, as long as native plants are not harmed. Wild rice removal always requires a permit.
For more information regarding aquatic plant management, please contact the Aquatic Plant Management Coordinator in your area, the UW-Extension Lakes Program(Exit DNR) (715-346-2116) or Wisconsin Association of Lakes(Exit DNR) (800-542-5253).
Aquatic Plant Protection
Aquatic plant protection begins with us. We need to work to maintain good water quality and healthy native aquatic plant communities. How can we do it? The first step is to limit the amount of nutrients and sediment that enter the lake. There are other important ways to safeguard a lake's native aquatic plant community. They may include developing motor boat ordinances that prevent the destruction of native plant beds, limiting aquatic plant removal activities, designating certain plant beds as Sensitive Area Sites and preventing the spread of invasive plants, such as Eurasian watermilfoil.
If plant management is needed, it is usually in lakes that humans have significantly altered. If we discover how to live on lakes in harmony with natural environments and how to use aquatic plant management techniques that blend with natural processes rather than resist them, the forecast for healthy lake ecosystems looks bright.
Produced by: Wisconsin Department of Natural Resources, Bureau of Fisheries Management and Habitat Protection
More information on this topic: Frank Koshere,
WDNR - Superior Service Center
1401 Tower Avenue
Superior, WI 54880