Phragmites grows in marsh in Hoopers Island, Md., on Dec. 10, 2009. Phragmites has feathery seed plumes at the top of round, erect stems. (Photo by Matt Rath/Chesapeake Bay Program)
Phragmites advances rapidly by underground rhizomes, which can sspread several feet per growing season. (Garrett and Kitty Wilkin/Flickr)
Phragmites is common in disturbed places such as ditches, roadsides and dredged areas. (sameold2010/Flickr)
Phragmites forms large, dense stands that crowd out other plants. (Fuzzy T/Flickr)
By the first frost, phragmites leaves die and fall off, leaving only dead brown stems and plumes. (Adrian Jones/IAN Image Library)
Phragmites grows along the edges of waterways such as rivers. (Jane Hawkey/IAN Image Library)
Phragmites is a non-native, invasive perennial plant that grows in wetlands and along roadsides and shorelines throughout the Chesapeake Bay watershed.
Appearance
Phragmites have feathery seed plumes at the top of tall, stiff stems. Young plants have purplish-brown seed plumes that turn tan or whitish as the plant matures. Phragmites' sheath-like leaves grow two feet in length and taper to a point at the tip. Their foliage is gray-green during the growing season. Gray-green foliage during the growing season. In autumn, foliage turns brown and most leaves drop off, leaving only the feathery plumes. Phragmites can grow to 15 feet tall.
Reproduction and Life Cycle
Feathery plumes begin to appear in June, and by August, they are filled with seeds. Plants cross-pollinate in late August and early September. In autumn, phragmites sheds its seeds, which are spread by wind and water. By the first frost, the plant’s food reserves move from its leaves to its rhizomes. The leaves die and fall off, leaving only dead brown stems and plumes. Pragmites also spread rapidly by rhizomes, which form a dense underground network that can be several feet deep and spread several feet horizontally in a single season. New seedlings begin to grow in early spring of the next year.
Did You Know?
- Phragmites comes from the Greek word Phragma meaning “fence." They are also known as common reed or reed grass.
- They were introduced to the United States in the 19th century when ships from Eurasia inadvertently carried phragmites seeds in their ballast. Although there is a type of phragmites that is native to the U.S., it is very rare.
- Unlike many native wetland plants, phragmites is not a valuable food source for waterfowl.
Sources and Additional Information
- Life in the Chesapeake Bay by Alice Jane Lippson and Robert L. Lippson
- PLANTS Profile for Phragmites australis – USDA Natural Resources Conservation Service
- Phragmites australis – U.S. Forest Service
- Phragmites – Pennsylvania Sea Grant
- Plant Conservation Alliance Alien Plant Working Group: Common Reed – National Park Service
Quick Facts
Species
Invasive
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Habitat
Grows in fresh and brackish wetlands and along river banks and shorelines; common in disturbed places such as ditches, roadsides and dredged areas. Forms large, dense stands that crowd out other plants.
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Range
Native to Europe and Asia; grows throughout the entire Chesapeake Bay watershed.
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Status
Stable
