Managing Phragmites with Herbicide

Herbicide can be the most effective method of non-native Phragmites management when it is used as a component of a comprehensive and integrated management approach.

There are at least two herbicides (glyphosate and imazapyr) that are effective at managing non-native Phragmites stands and are commercially available under a variety of names in the United States and Canada. These chemicals are not species specific, so care must be taken to avoid harming native plants. Imazapyr remains active in the soil longer than glyphosate, and threfore, can have greater non-target impacts if used in areas with greater plant diversity. Additionally, different chemical formulations are available for application over land and over water. It is importantto use the formulation approved for aquatic use, because overland formulas can harm amphibians, fish, and invertebrates. For more information about herbicide impacts on amphibians and reptiles, see p. 19-20 and 71-72  of the Michigan Amphibian & Reptile Best Management Practices document.

Phragmites "witches broom" regrowth after Glyphosate treatment of the stand at Harsens Island, MI. Photo credit: phragmites.org

Phragmites “witches broom” regrowth after Glyphosate treatment of the stand at Harsens Island, MI. Photo credit: phragmites.org

When using herbicide to manage non-native Phragmites, if the entire clone is not killed, the remaining rhizomes may produce new stems the following year. In some cases, these take the form of a “witches broom” growth, with many small stems growing from a single node that may be buried or exposed. Resprouting stalks and witches brooms require follow-up herbicide treatment.

Regulations on the application of herbicides are different across the country and between the U.S. and Canada. Check with local authorities before purchasing and applying herbicides. Methods used to apply herbicide vary depending on the size of the area requiring treatment, the density of the Phragmites stands, the composition of the surrounding vegetation, and the capacity of the management team.

For more information on herbicide application see: A guide to the control and management of invasive Phragmites by the Michigan Department of Natural Resources.

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Phragmites Herbicide Treatment Quick Guide

The Non-native Phragmites Herbicide Quick Guide provides an easy reference sheet for mixing the correct quantities of herbicide for non-native Phragmites management. This one-page (double-sided) guide can be printed and left in work trucks or with mixing equipment. It will be updated as new research improves management best practices.

Approved Herbicides by State and Province

The Great Lakes states and provinces have many regulations and standards for herbicide and pesticide treatments that can be explored in detail on the websites below. Please contact your state or provincial agencies for more information. If you know of additional or updated resources, please email phragmites@glc.org.

The necessity for a permit may depend on many factors including proximity to standing water, wetlands and Great Lakes shoreline. The links below will help you determine which permits, if any, are necessary for your site.

 State

 Approved Herbicides

 Permitting Information

Illinois

Illinois Approved Herbicides

Use the search tool to find registered herbicides

Illinois NPDES permit

NPDES Permit

Illinois Nature Preserve Vegetation Management Guidelines

Illinois Nature Preserve Commission’s Vegetation Management Guideline for Phragmites

Indiana

Indiana Approved Herbicides

Use the search tool to find registered herbicides

Indiana Permitting Information

Aquatic vegetation control permit

Michigan

Michigan Approved Herbicides

Approved aquatic herbicides

Michigan Permitting Information

Phragmites specific permit information

Minnesota

Minnesota Approved Herbicides

Approved aquatic herbicides

Minnesota Permitting Information

Aquatic plant management permit

New York

New York Approved Herbicides

Use the search tool to find registered herbicides

New York Permitting Information

Application for a permit to use a pesticide for the control of an aquatic pest

NYSDEC Primer on Aquatic Plant Management

Aquatic Pesticide Use Information (see page 48)

Ohio

Ohio Approved Herbicides

Approved aquatic herbicides

Ohio Applicator Information

Herbicide applicator information

Ohio Permit Notification

Information about when a permit is necessary

Pennsylvania

Pennsylvania Approved Herbicides

Use the search tool to find registered herbicides

Pennsylvania Permitting Information 2

Permit For Use of an Algicide, Herbicide or Fish Control Chemical in Waters of the Commonwealth

Pennsylvania Permitting Information

General and NPDES permit information

Wisconsin

Wisconsin Approved Herbicides

Use the search tool to find registered herbicides

Wisconsin Herbicide FAQs

FAQ about herbicide use and approval

Wisconsin Permitting Information

Aquatic plant management permit

Wisconsin Phragmites Management Information

Phragmites Management Information

Ontario

Ontario Approved Herbicides

List of approved herbicides

Ontario Permitting Information

Pesticide permits (choose “Pesticide Permits” from the list on the right)

Quebec

Quebec Approved Herbicides

Classification and overview of pesticides

Quebec Permitting Information

Permit application and certificates

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