ORIGIN

Tropical South America

COMMON NAME

Water hyacinth

BOTANICAL NAME

Eichornia crassipes

IDENTIFICATION

A floating aquatic perennial, with distinctive bladder-like swollen leaf petioles giving buoyancy. Flowers conspicuous, above foliage, near-white with purple markings and a distinct yellow spot.

HABITATS

Ponds, slow-moving streams.

IMPACT TO BIOTA AND ECOSYSTEMS

An aggressive invasive, choking ponds and slow-moving water and replacing the natural flora. Twenty-five plants can produce a mat over 1 hectare of water in one temperate growing season.

DISPERSAL ROUTES, VECTORS, INFESTATION SOURCES

Seeds and plants can be dispersed by water movement, wind, movement of machinery and equipment, and, planned or accidental planting and release by humans.

MANAGEMENT

Control work is only to be carried out by persons authorised by AgriQuality. Eradication methods include hand or mechanical clearance, as well as the use of some approved herbicides.

Physical Control
Hand clearance is effective on small sites.

Disposal
Mulching on dry land is effective or dry out and burn.

Chemical Control
Chemicals used to treat water hyacinth include 2,4-D Amine and Glyphosate.

Biological Control

Recommended Approach
Report to AgriQuality or a Pest Plant Officer.

FURTHER COMMENT

Water hyacinth is a Notifiable Pest Plant and landowners/occupiers have a legal obligation to report the presence of this plant to AgriQuality and/or your local Pest Plant Officer who will arrange for the necessary eradication work. It is an offence for anyone to grow this plant. Notifiable Pest Plants are deemed to pose an intolerable threat to NZ and must be eradicated. The Government pays for and organises all eradication work needed on this plant.

For more information on Water hyacinth please refer to Environment Bay of Plenty's Fact Sheet pp1300-Aquatic Pest Plants

This plant is prohibited from propagation, sale and distribution within New Zealand!