October 4, 2014

Phragmites australis (frag-MY-teez), also known as common reed, is a perennial, wetland grass that can grow to 15 feet in height. phragWhile Phragmites australis is native to Michigan, an invasive, non-native, variety of phragmites is becoming widespread and is threatening the ecological health of wetlands and the Great Lakes coastal shoreline. Invasive phragmites creates tall, dense stands which degrade wetlands and coastal areas by crowding out native plants and animals, blocking shoreline views, reducing access for swimming, fishing, and hunting and can create fire hazards from dry plant material.

Invasive Phragmites can be controlled using an integrated pest management approach which includes an initial herbicide treatment followed by mechanical removal (e.g., cutting, mowing) and annual maintenance. For large areas with dense stands of invasive Phragmites, prescribed burning used after herbicide treatment can provide additional control and ecological benefits over mechanical removal.  Early detection is key to preventing large dense stands and is also more cost efficient.

Great Lakes basin wide Phragmites information through the Great Lakes Phragmites Collaborative (GLPC) is available at: http://greatlakesphragmites.net/.  The GLPC is a regional partnership established to improve communication and collaboration and lead to more coordinated, efficient and strategic approaches to Phragmites management, restoration and research across the Great Lakes basin.

What You Can Do

Determine whether the plants are native or invasive Phragmites (or another plant species). Useful websites for identification include:

  1. Midwest Invasive Species Information Network
  2. MNFI, Phragmites: Native or Not?
  3. Cornell University

Read the following publications to better understand the management issues and control options: A Guide to the Control and Management of Invasive Phragmites, from DEQ and partners.

Controlling invasive Phragmites may require one or more permits from local, state and federal authorities, as several environmental laws may be applicable. If necessary, apply for and obtain the appropriate permit(s):

a. Chemical Treatment: For inland areas (including lakes, ponds, rivers, streams, ditches, wetlands, etc.), a permit is required to treat invasive Phragmites using herbicides if the plants are in standing water at the time of treatment.  Some small backyard ponds may be exempt from permitting requirements, depending on their characteristics. For shoreline areas along the Great Lakes and Lake St. Clair, a permit is required to chemically treat any plant located below the ordinary high water mark, regardless of whether there is standing water or not. The MDEQ’s Water Resource Division has created a general permit category for this type of activity, which allows property owners to request authorization for control of invasive or non-native species through a simplified permit process.

For chemical treatment information including permitting requirements and blank permit application forms visit www.michigan.gov/deqinlandlakes (Select Aquatic Nuisance Control) or contact the Aquatic Nuisance Control Program, Water Resources Division, at 517-284-5593. Please read  the General Permit for Aquatic Nuisance Control Activities for Certain Non-native Invasive Emergent Plants for specific information, including information about Phragmites.

The use of a licensed applicator who is certified in aquatic pest management is recommended for herbicide application, especially in large, dense stands and in sensitive areas such as wetlands:  Pesticide Application Businesses Licensed by the State of Michigan. (For inland areas, search under Category 5, Aquatics; for Great Lakes shoreline, search by Category 5 for wet areas and Category 6, Right-of-Way, for dry areas).

b. Mechanical Treatment:  Mechanical treatment (i.e., mowing) of invasive Phragmites is recommended after chemical treatment (at least 2 weeks after, for maximum effectiveness of the chemical treatment), to remove dead stems and promote native plant growth.  Mowing is the most commonly used method for mechanical treatment, particularly on privately owned, or smaller properties.  If mowing is used as the mechanical treatment method, the vegetation cutting should be conducted only in those areas where invasive Phragmites is present, avoiding adjacent wetland areas where native species are dominant.  In wet areas, mowing invasive Phragmites as mechanical treatment is most often done in the winter when the ground is frozen, which provides better and safer access to these areas, as well as minimizes impacts to small animals and native plants. Mowing invasive Phragmites as mechanical treatment does not require a permit, except in the St. Clair Flats, from the State of Michigan, but special care should be taken to avoid significant rutting or displacement of soil, which does require a permit. For more information on mechanical treatment of invasive Phragmites, please contact the Water Resources Division at 517-284-5473.

Tilling or disking of plant roots and soil is not an effective mechanical treatment method for invasive Phragmites.  These activities promote the spread of invasive Phragmites, as the broken rhizomes and seeds are dispersed and sprout new growth.

Prescribed burning is another very effective method of mechanical treatment of invasive Phragmites after chemical treatment. This method is typically used on very large sites, and in more rural areas. Prescribed burning does not require a permit from the State of Michigan, but often does require approval from the local unit of government.  Some municipalities require additional approvals for certain activities, such as controlled burns. Please contact your local authorities for more information.

SOURCE: 2014 www.michigan.gov/deq