Emergent, aquatic, perennial herb < 1.5 m tall. Stems are hollow when mature, buoyant and form dense floating mats. Leaves are < 20 x 5 cm. Flowerheads are white, clover-like and borne in December – May. Seeds ripen in summer – autumn.
To help protect our environment:
Damp soils, still or slow-moving water body margins.
Sets seed. Vegetative spread from stem fragments. Seed and stem fragments dispersed by water movement. Human-mediated dispersal through contamination of machinery and deliberate plantings.
Forms floating mats, blocking streams and drainage tunnels, altering water flow dynamics and exacerbating flooding. Potential to replace short-stature herbaceous wetland plant communities. May impact mauri of wai māori.
Do not attempt to undertake control of this species. Please report to Auckland Council.
CAUTION: When using any herbicide or pesticide please read the label thoroughly to ensure that all instructions and safety requirements are followed.