Te Henga, Auckland’s largest remaining wetland and home to several threatened native species, was aerially sprayed with glyphosate for willow control for a second consecutive summer, prompting the Te Henga Wetland Collective to pursue a legal challenge through the Environment Court.
The wetland, in Waitakere, West Auckland, provides habitat for the matuku-hūrepo (Australasian bittern), mātātā (fernbird), pūweto (spotless crake), pāteke (brown teal), and pekapeka tou-roa (long-tailed bat) — several of which are classified as threatened.
Spraying took place in both the 2025 and 2026 summers as part of a willow control programme. Local residents have raised concerns about the method’s impact on non-target vegetation and the risk to the wetland’s waterways and wildlife. An application was filed with the Environment Court seeking an interim enforcement order to halt the aerial spraying, but the operation went ahead regardless.
A technical review identified two products reportedly used in the operation — Polaris 450 (a glyphosate isopropylamine salt formulation) and a surfactant adjuvant — and noted that the manufacturer’s own Safety Data Sheet explicitly instructs users not to allow the product to enter waterways.
With the support of experienced lawyers, the Te Henga Wetland Collective is challenging aspects of the approval process through the courts, seeking to ensure that decisions affecting sensitive ecosystems are properly assessed, independently scrutinised, and held accountable under the law.
LeVonne Scott, spokesperson for the Te Henga Wetland Collective, said: “Wetlands take decades to recover from chemical damage, and some of it never recovers at all. We’re not opposed to dealing with willow — we’re asking that it’s done in a way that doesn’t put threatened species and waterways at risk, and that the process is open to proper scrutiny.”
The Collective has launched a fundraising appeal to cover independent ecological assessments, expert evidence, and legal costs associated with the court challenge.
