There are over 1,650 naturalised weed species in New South Wales and more than 340 of these impact our native species.
Many weeds that threaten biodiversity are widespread and total eradication is not practical or possible. Management strategies aim to reduce the impact of widespread weeds on native species and ecological communities.
Management programs focus on areas where control is both achievable and likely to have the greatest benefit to native biodiversity. Such a site-led approach ensures the best possible outcome from the limited resources available for managing widespread weeds.
Mechanisms used for strategic management of widespread weeds include:
- listing weeds as key threatening processes under the Biodiversity Conservation Act 2016
- the Saving our Species (SoS) program
- Biodiversity priorities for widespread weeds (BPWW)
- NPWS regional pest management strategies (RPMS).
Under the previous Act, the Threatened Species Conservation Act 1995, some weeds were managed using a Threat Abatement Plan (TAP). This approach has been expanded and included in strategic planning for the BPWW and the Saving our Species program.
Weed key threatening processes currently active in New South Wales:
- African olive
- bitou bush and boneseed
- exotic perennial grasses
- exotic vines and scramblers, including Asparagus weeds
- Lantana camara
- scotch broom.
To assess the effectiveness of weed control in delivering the desired biodiversity outcomes, a set of monitoring guidelines were created. The effectiveness of weed control relies not only on the response of the weeds to the control but also on the response of the native species, population or ecological communities at which the conservation efforts are aimed.
The monitoring guidelines are based on the threat abatement plan of the first invasive species listed as a key threatening process, bitou bush and boneseed (Chrysanthemoides monilifera).