Wednesday, 04 March 2020 10:51

Invasive weed water hyacinth found in Waikato River 

Written by  Staff Reporters
Water hyacinth. Image: Biosecurity New Zealand. Water hyacinth. Image: Biosecurity New Zealand.

An invasive weed that can reduce water quality and block irrigation systems has been discovered in the Waikato River.

A joint Biosecurity New Zealand and Waikato Regional Council work programme is now underway to remove the small cluster of the pest water hyacinth in the river near Huntly.

The agencies are working together with local iwi to ensure any water hyacinth present is located and safely removed. The team will then coordinate ongoing checks to make sure it hasn't come back.

Biosecurity New Zealand's manager of pest management, John Sanson, says water hyacinth is a rapidly growing water weed that if left, can form dense mats that reduce water quality, crowd out native water plants and animals, block irrigation systems and alter ecosystems.

"In this instance, we've found just 2 individual plants in the slow waters at the edges of the river and 1 plant in a cluster of willows further out into the stream.

"The plants have clearly come from a container of water hyacinth being kept at a private property in Huntly backing onto the river. This container was close to a drain next to the river bank and we believe that's how the plants entered the waterway."

Sanson says all known plants have been removed from the water and inspections have found no further sign of the weed.

However, as a precaution, a more comprehensive survey is taking place today, using a boat supplied by the council harbour master. 

It is illegal to sell, propagate or distribute water hyacinth. Those who may have seen the pest can call Biosecurity New Zealand’s pests and diseases hotline on 0800 80 99 66.

More like this

Stinging response

OPINION: MPI's response to the yellow-legged hornet has received a mixed report card from New Zealand Beekeeping Inc (NZBI), with praise for the Ministry's expansion of response funding and front-line efforts in Auckland, but a sting in the tail - criticising MPI for not focusing enough on regions outside the big smoke.

Featured

2026 fresh produce trends shaping Kiwi food culture

According to the latest Fresh Produce Trend Report from United Fresh, 2026 will be a year where fruit and vegetables are shaped by cost pressures, rapid digital adoption, and a renewed focus on wellbeing at home.

Editorial: Having a rural voice

OPINION: The past few weeks have been tough on farms across the North Island: floods and storms have caused damage and disruption to families and businesses.

National

Machinery & Products

» Latest Print Issues Online

The Hound

Realpolitik!

OPINION: Meanwhile, red blooded Northland politician Matua Shane Jones has provided one of the most telling quotes of the year…

The Kiwi way

OPINION: This old mutt has been around for a few years now and it seems these ‘once in 100-year’ weather…

» Connect with Rural News

» eNewsletter

Subscribe to our weekly newsletter