New rules have been imposed on 45 plant nurseries as a major biosecurity operation continues in Kerikeri.
About 100 people are involved in the operation, led by the Ministry for Primary Industries (MPI), which aims to stop the spread of the potentially deadly plant disease myrtle rust.
The fungus was found at a Kerikeri plant nursery on May 2 and, if overseas experience is anything to go by, could be devastating for native species such as pohutukawa, rata and manuka, as well as many garden and commercial plants.
The directors-general of MPI and the Department of Conservation were in Kerikeri yesterday where they visited Kerikeri Plant Production, the epicentre of the outbreak, and announced new biosecurity measures affecting 35 plant nurseries and retailers in the Bay of Islands town.
The rules also apply to another 10 businesses around the country which bought plants from the infected nursery.