Southern Naiad

Also known as:
Southern Water Nymph
North and South America

General description

Submerged aquatic. Stems slender, branching and < 90 cm long. Leaves are narrow, opposite or in whorls, toothed and tapered to a blunt or pointed tip. Flowers are small, inconspicuous and borne in leaf axils.

What you need to know

To help protect our environment:

  • You must not breed, distribute, release or sell southern naiad. As southern naiad is an Unwanted Organism, these restrictions apply within the Auckland region and across the whole of New Zealand.

Still or flowing freshwater bodies, lakes, stream, ponds, ditches.

Seeds dispersed by water. Vegetative spread from stem fragments. Human-mediated dispersal through movement of contaminated boats and equipment.

Can form dense infestations, outcompeting native plants and clogging waterways.

Site Management

Consider engaging an aquatic pest plant control operator to control large infestations. Follow up treated areas each year.

Recommended approaches

Physical control

Method: Rake up and pull out between November and January

Plant parts requiring disposal: All parts

Disposal options: Leave onsite to rot down away from the water


Biocontrol is currently not available for this species.

Community agrichemical control recommendations

Certified Handler/Experienced agrichemical user
Follow up in summer after pulling out plants with a foliar spray of 100 ml glyphosate green per 10 L of water

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

Similar species

Hydrilla verticillata

Hydrilla lacks the short branches between the stem and the leaves.

Egeria densa

Egeria lacks the short branches between the stem and the leaves. Egeria's leaves have smooth margins.

Lagarosiphon major

Hydrilla lacks the short branches between the stem and the leaves.

Search tags

RPMP status

Unwanted Organism
Southern naiad - Main species image