Stems grow up to 8 feet in length
Still or slow-moving fresh waters
Found in the upper Chesapeake Bay and in freshwater streams, rivers, lakes and ponds throughout the Bay watershed. Also grows in the low salinity waters of some moderately brackish tidal rivers such as Maryland’s Middle River and the Potomac River near Alexandria, Virginia.
Coontail is made up of slender, densely branched stems that can grow to 8 feet long. Branches have stiff, forked leaves with fine teeth along one edge. Leaves grow in whorls of 9 to 10 along each stem. Whorls become more crowded toward the tip of the stems.
Leaves keep their shape when taken out of the water. Because these plants do not have a true root system, they float freely in the water.
Migratory waterfowl feed on coontail.
Reproduction and Life Cycle
This grass usually reproduces asexually when stem fragments break off in autumn, overwinter on the bottom and develop into new plants in spring. It also occasionally reproduces sexually when the plants flower and produce tiny nut-like seeds.
Did You Know?
- Coontail gets its name from its appearance, which is similar to a raccoon’s tail. It is also known as hornwort.
- This underwater grass is usually found in areas with moderate to high nutrient levels. Coontial floats in dense masses just beneath the water’s surface and can also grow near the bottom in channels and other deep areas. It can sometimes found within large beds of other types of underwater grasses.
- Coontail provides important shade, shelter and spawning areas for some fish. Migratory waterfowl feed on coontail.
- It can be confused with Eurasian watermilfoil. You can distinguish coontail by its stiff leaves that keep their shape when taken out of the water.
Sources and Additional Information
- Underwater Grasses in Chesapeake Bay & Mid-Atlantic Coastal Waters by Maryland Sea Grant
- Life in the Chesapeake Bay by Alice Jane Lippson and Robert L. Lippson
- Chesapeake Bay: Nature of the Estuary, A Field Guide by Christopher P. White
- Underwater Grass Key: Coontail – Maryland Department of Natural Resources
- Weed Identification Guide: Coontail – Virginia Tech
- PLANTS Database: Ceratophyllum demersum – USDA Natural Resources Conservation Service