The effects of weeds
Auckland's exotic weeds far outnumber its native plant species. We have widespread ones like the moth plant and less common ones like balloon vine or cathedral bells.
Weeds can have adverse effects on people and the environment by:
- causing allergies and health problems
- damaging infrastructure
- affecting heritage sites
- reducing amenity values in public spaces
- invading sports fields and other playing surfaces (including artificial turf)
- increasing the cost of asset maintenance and shortening the lifespan of assets
- negatively impacting on Māori cultural values
- invading areas of native vegetation, preventing seedlings from regenerating and out-competing native species
- reducing habitat for native fauna
- changing ecosystem types and reducing biodiversity
- reducing water quality
- impacting on primary industry, e.g. by reducing available grazing area.
The Weed Management Policy promotes methods that have the least potential for adverse effects.
The policy has eight objectives:
- Take an integrated approach to weed management and vegetation control.
- Ensure best practice in weed management and vegetation control.
- Minimise agrichemical use.
- Minimise non-target effects of agrichemical use.
- Ensure public health and safety.
- Protect and enhance the environment.
- Empower the community to manage weeds under the policy.
- Deliver weed management and vegetation control which is value for money.
How we control weeds and vegetation
We use different weed control methods depending on the species, site characteristics, infestation level and wider landscape characteristics.
We choose methods that have the least adverse effects on people and the environment.
Current control methods are:
- manual control
- mechanical control
- organic herbicide
- biological control
- hot water and steam.
Sometimes we do not control weeds that provide a habitat for indigenous species. An example of this species is gorse.
Together with council-controlled organisations, we control more than 200 weeds in local and sports parks, regional parks, the road corridor and waterways.
Many of these are pest plants (environmental weeds).
For more information on pest plants and what we do for biosecurity, see
Pests and weeds.
Join our no-spray register
To find out about our no-spray register, see Why and how we control weeds.
Get a copy of the Weed Management Policy