Something is silently strangling the life out of the Chesapeake Bay. Like a disease, this contagious invader infects its host and then, undetected, spreads to another victim. Considered one of the most destructive invasive species impacting the Atlantic coast, phragmites has rapidly encroached into the rivers, creeks, and wetlands of the Chesapeake Bay.

Also known as common reed, phragmites is a perennial grass that grows primarily in fresh and brackish water, with stalks reaching up to 15 feet tall. Able to tolerate various environmental conditions and disturbed habitats, it quickly colonizes new areas and produces dense stands that dominate both tidal and non-tidal wetland areas. By out-competing native wetland plants, phragmites reduces natural species diversity, thus reducing the number of wildlife species that can use food and cover in wetland habitats.

Phragmites can be controlled by using a combination of physical and chemical treatments. Physical treatments include burning, mowing, discing, flooding, or draining. Chemical treatments include spraying with herbicides that can be used safely in aquatic environments. Biologists spray an herbicide with an ingredient called glyphosate onto the leaves of phragmites, which flows down into the roots to kill the plant. They will also hand-spray peripheral areas of phragmites with an herbicide, while a helicopter applies it aerially to large stands. The most successful time of the year to treat phrag mites is from late July through October, when plants are actively growing.

The U.S. Fish & Wildlife Service Chesapeake Bay Field Office is working with our partners to control phragmites and protect the native plants and animals of the Bay.

In partnership with Maryland Department of Natural Resources, CBFO sprayed herbicide on 180 acres of invasive phragmites along the Patuxent River in Prince George ’s and Calvert County , Maryland . This tract was identified as a priority area to control phragmites because of its potential habitat value for native wildlife, especially for migratory waterfowl. By managing invasive species such as phragmites, we can begin to restore the natural ecosystem balance to the Bay.

Phragmites australis, USFWS photo
Phragmites australis - Photo by Joe McCauley, USFWS

Spraying herbicide on Phragmites from a helicopter
Helicopter spraying herbicide on phragmites stand - Photo, USFWS

Tidal marsh with Phragmites stand invading native vegetation - Photo, USFWS
Tidal marsh with Phragmites stand invading native vegetation - Photo, USFWS

For more information:

Chesapeake Bay Program - Phragmites

Maryland Department of Natural Resources - Phragmites