Potamogeton crispus

Curled pondweed

Also known as:

Curly pondweed, curly-leaf pondweed

Family: Potamogetonaceae

Origin: Africa, Australia, Eurasia

Curled pondweed underwater.
It forms dense mats in the water.
Photo credit: Richard Old, XID Services, Inc

Regional Pest Management Plan (RPMP) status

  • Not a legally declared pest

View more about the RPMP statuses

General description

Perennial, submerged, bottom-rooting aquatic herb. Stems are flattened, < 1 m long and branching. Leaves are alternate, linear, translucent and finely toothed near the tip, with wavy margins. Flowers are small, green and borne on spikes in November – January. Turions are formed in leaf axils and at stem tips.

What you need to know

Although curled pondweed is not a legally declared pest plant, it may still be invasive in some situations. Consider lower-risk alternatives for your garden, such as native plants.

Habitats

Lakes, rivers, streams, ponds, reservoirs, ditches, estuaries, marshes.

Dispersal

Sets seed. Vegetative spread from rhizomes, stem fragments and turions. Propagules dispersed by water and birds. Human-mediated dispersal through movement of contaminated boats, equipment and machinery.

Impact on environment

Forms dense stands, outcompeting native plants, suppressing regeneration and altering habitat structure.

Control

Site Management

Very difficult to control once established. Requires an aquatic pest plant control operator. Contact Auckland Council for control options.

Recommended approaches

Physical control

Method: Pull out.

Plant parts requiring disposal: All parts.

Disposal options: Remove to greenwaste or landfill if practical.

Biocontrol

Biocontrol is currently not available for this species.

Caution: When using any herbicide or pesticide please read the label thoroughly to ensure that all instructions and safety requirements are followed.

Drawings of curled pondweed.
Leaves have distinct wavy edges.
Photo credit: Richard Old, XID Services, Inc
Close up of a curled pondweed leaf.
The leaves may be bright green-olive green.
Photo credit: Richard Old, XID Services, Inc
Close up of curled pondweed with small frilled leaves.
Curled pondweed is a submerged aquatic plant that has green to red/brown leaves arranged alternately on stems.
Photo credit: Richard Old, XID Services, Inc