Curly Pondweed

Potamogeton crispus

Curly pondweed has broad leaves with curly, fine-toothed edges.

• Its leaves grow to about 1 to 4 inches long.
• Leaves grow alternately or slightly opposite on flat, branched stems.
• Leaf color and shape varies with the season: In winter, leaves are blue-green and more flattened. In the spring and summer, leaves are reddish-brown and become wider and curlier.
• It has a shallow root and rhizome system.

Where does curly pondweed grow?

Curly pondweed grows in fresh non-tidal to slightly brackish tidal waters, including streams, rivers and reservoirs throughout the Bay watershed.

How does curly pondweed reproduce?

Curly pondweed has a three-stage life cycle.

• During the spring/summer form, flowers bloom and float at the water's surface.
• Curly pondweed begins to die in mid-summer, after the plants have produced vegetative buds. These buds lie dormant until the fall.
• During its winter form, the plant's spring/summer cycle repeats itself when the vegetative buds sprout into new flowers.

Curly pondweed can also reproduce asexually when:

• Lower horizontal stems (called rhizomes) extend to form new plants
• Burr-like structures near the tips of the stems develop into new plants.

Other facts about curly pondweed:

• Curly pondweed is native to Europe. It was likely introduced to the U.S. in the mid-1800s. Curly pondweed is considered invasive in non-tidal waters like lakes and reservoirs.
• Curly pondweed can be confused with young shoots of redhead grass.