
National pest plant programmes
http://www.gw.govt.nz/national-pest-plant-programmes

The National Pest Plant Accord (NPPA) is a co-operative agreement between the Nursery and Garden Industry Association of NZ, regional councils and government departments with biosecurity responsibilities (primarily the Ministry of Primary Industries and the Department of Conservation).

Smilax infestation
The plants listed under the NPPA have been declared unwanted organisms under the Biosecurity Act 1993. This prevents their sale, propagation or distribution across the country. Regional councils undertake surveillance to prevent the commercial sale and/or distribution of these plants.
Greater Wellington biosecurity officers periodically inspect all plant outlets in the region to ensure that they are not selling any NPPA or species in the RPMS. In addition to this a selection of markets are inspected at random intervals.
A copy of the 2008 version of the NPPA can be downloaded here
Greater Wellington supports and participates in the weedbusters programme
Weedbusters is a national weeds awareness and education programme that aims to protect New Zealand's environment from the increasing weed problem. People play a large part in spreading environmental weeds, often without knowing it, and weedbusters aims to educate people and raise awareness to turn this problem around.