Curly Pondweed

Potamogeton crispus

Quick Facts

  • Species

    Nonnative

  • Habitat

    Grows in fresh non-tidal to slightly brackish tidal waters.

  • Range

    Native to Europe; found in the upper Chesapeake Bay and in tributaries such as streams, rivers, lakes and reservoirs throughout the Bay watershed.

  • Status

    Stable

Curly pondweed is a bay grass with broad, curly leaves along flat, branched stems. It grows in fresh non-tidal to slightly brackish tidal waters throughout the Chesapeake Bay watershed.

Appearance

Curly pondweed is made up of broad leaves with curly, finely toothed edges. These leaves grow to 1 to 4 inches long and grow alternately or slightly opposite on flat, branched stems. In winter, leaves are blue-green and more flattened; in spring and summer, leaves are reddish-brown and become wider and curlier. Curly pondweed has a shallow root and rhizome system.

Reproduction and Life Cycle

Curly pondweed has a three-stage life cycle. During spring and summer, flowers bloom and float at the water’s surface. It begins to die in mid-summer after producing buds, which lie dormant until autumn. In winter, the spring/summer cycle repeats itself when buds sprout into new flowers. It can also reproduce asexually when rhizomes or burr-like structures near the tips of the stems develop into new plants.

Did You Know?

  • Curly pondweed was likely introduced to the United States in the mid-1800s.
  • It can become invasive in non-tidal waters because it grows early in the season and can shade out other bay grasses.
  • Curly pondweed can be confused with young shoots of redhead grass.

Sources and Additional Information

Quick Facts

  • Species

    Nonnative

  • Habitat

    Grows in fresh non-tidal to slightly brackish tidal waters.

  • Range

    Native to Europe; found in the upper Chesapeake Bay and in tributaries such as streams, rivers, lakes and reservoirs throughout the Bay watershed.

  • Status

    Stable