Identification and Reproduction

Identification

• Curly pondweed has wavy, toothed, alternate leaves.
• The leaves become denser at the bottom of the stem.
• The serrated leaves are a unique distinguishing feature of this species.
• The leaves are green, reddish, or brown, and the plant has yellow or red rhizomes.
• The plant grows up to five metres long, and forms dense mats of vegetation.

Reproduction

• It has a winter annual type of life cycle.
• It reproduces vegetatively with buds called “turions” which develop over winter.
• It is one of the first aquatic plants to begin growing in spring, and it grows quickly during the season.
• It also produces small flowers that can be found above water.
• The flowers are in a terminal spike and have small fruits which it uses to reproduce sexually.

Habitat & Ecology

• This plant can grow at cold temperatures and with little light.
• It prefers brackish or alkaline water, and can easily thrive in polluted waters.
• It survives over winters even under frozen water.
• Curly pondweed is found in rivers, streams, marshes, and ponds.

Impacts

Ecological: 

• The dense colonies produced by Curly pondweed can block aquatic activity and obstruct fish movements.
• The vegetation can create eutrophication (increased phosphorus concentrations in waterways), which cause blooms of algae.
• The plant outcompetes native aquatic vegetation and reduce biodiversity.

Management

• Prevent transport of Curly pondweed by cleaning, draining, and drying boats and other aquatic equipment after leaving bodies of water.
• Do not purchase Curly pondweed as aquarium vegetation. Never dispose of aquarium plants into drains or waterways.

Mechanical/Manual Control:

• Mechanical removal can be done by raking out the plant early in the season, but this will not remove all parts of the plant.
• Any plant parts removed should be disposed of in a landfill.
• Benthic barriers can also be used to restrict light and growth. 
  

Resources

For more identification and control methods for curly-leaf pondweed check out the Invasive Species Council of Manitoba's page here. 

Header photo (Leslie J. Mehroff).