Environmental issues

Pests and weeds

Widespread weed management priorities

Biodiversity priorities for widespread weeds in NSW

In New South Wales, weeds pose the second greatest threat to biodiversity after land clearing and habitat loss. Many weeds that threaten biodiversity are widespread and usually beyond the scope of eradication programmes developed to deal with emerging weed threats. To reduce the impact of widespread weeds on biodiversity (biological assets), control programmes need to be prioritised to areas where control is both achievable and likely to have the greatest benefit to native biodiversity, independent of land tenure. Such a site-led approach will ensure maximum benefit from the limited resources available for managing widespread weeds.

To address this issue, the Office of Environment and Heritage (OEH) and the NSW Department of Primary Industries (DPI) worked with the former 13 catchment management authorities (CMAs) to develop regional biodiversity priorities for widespread weeds. The report for this collaborative project can be accessed via the DPI weed page.

The report is made up of 14 parts. This first section is an overarching document that outlines the statewide framework used to develop the regional priorities for management of widespread weeds for biodiversity conservation in each of the 13 CMA regions. This statewide framework comprises:

(i) background information

(ii) the objectives of the project

(iii) the standardised methodology used to establish regional priorities

(iv) guidance on implementing the priorities.

The remaining 13 parts (Parts A–M; one for each CMA region) document the specific assessment outcomes for each region using the approach outlined in the statewide framework. They provide guidance to aid decision-making and future investment in weed control for biodiversity conservation until 2015.

The threat abatement approach – asset protection

During the development of the Threat Abatement Plan (TAP) for the invasion of native plant communities by Chrysanthemoides monilifera (bitou bush and boneseed) in NSW, OEH developed a process for identifying and prioritising biological assets at risk from widespread weeds and sites for control. The TAP approach was subsequently applied to Lantana camara for the national Plan to Protect Environmental Assets from Lantana. This TAP approach was used in these instances to ensure management reduced the impacts of individual weed species on biological assets.

It is not feasible (or a good investment) to apply the TAP approach to every individual weed species impacting on biodiversity, as many have overlapping distributions, impacts and management requirements. A site-led approach that applies the TAP process to multiple weed species on a landscape scale was required. To ensure that management of widespread weeds has clear conservation outcomes OEH has established:

  • which widespread weeds pose a threat to biodiversity on a regional scale
  • what biodiversity is at risk and needs urgent protection
  • the sites where control will be most beneficial
  • the monitoring required to assess both the effectiveness of control and the response of biodiversity at risk.

As CMAs operated according to catchment boundaries and across all land tenures, it was appropriate to develop these site-led weed management priorities for biodiversity conservation on a regional or catchment-based scale in NSW.

Each CMA has a list of sites ranked into six categories (plus another category with sites requiring further information) for widespread weed control programmes aimed specifically at biological asset protection. Category 1 sites are the highest priority, representing where weed control is likely to be of greatest benefit to the biodiversity at risk. Long term management at these high priority sites is extremely important to reduce weed impacts and to help prevent the biological assets at risk moving closer to extinction. Therefore resources for widespread weed management aimed at conservation must be directed to the highest priority sites.

Page last updated: 06 August 2014