Open Access

John S. Benson

• This third paper in the NSW Vegetation Classification and Assessment series covers the NSW South-western Slopes Bioregion of 8.192 million hectares being 10% of NSW. A total of 135 plant communities, comprising 97 new communities and 38 previously described communities, are classified. Their protected area and threat status is assessed. A full description of the 135 plant communities is provided in a 400 page report, generated from the NSWVCA database, on the CD accompanying this paper. Eucalyptus-dominated grassy or shrubby woodlands and open forests are the main types of vegetation in the bioregion. The CD also contains a read-only version of Version 2 of the NSWVCA database that includes updated information on the plant communities previously published in Version 1 of the NSWVCA covering the NSW Western Plains. Six new communities are added to the Western Plains. The vegetation classification and assessment is based on published and unpublished vegetation surveys and map unit descriptions that are listed in the NSWVCA Bibliography on the CD, expert advice and extensive field checking. Over 80% of the native vegetation in the NSW South-western Slopes Bioregion has been cleared making it the most cleared and fragmented of the 18 IBRA Bioregions in NSW. Exotic plant species dominate the ground cover outside conservation reserves, state forests, roadsides and travelling stock reserves. As of September 2008 about 1.9% of the Bioregion was in 105 protected areas and 28 of the 135 plant communities were assessed to be adequately protected in reserves. Using NSWVCA Threat Criteria, 18 plant communities were assessed as being Critically Endangered, 33 Endangered, 29 Vulnerable, 25 Near Threatened and 30 Least Concern. Current threats include over-grazing, especially during drought, exotic species dominance of the ground cover, impacts of fragmentation on species persistence and genetic diversity and impacts of lower rainfall due to climate change. To address these threats, linking and enlarging vegetation remnants through revegetation (including regenerating native ground cover) is required. Some progress is being made through re-vegetation schemes driven by the NSW 2003 Natural Resource reforms, however, more incentive funding for landholders would accelerate the re-vegetation program.