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Semi-permanent quadrats, located in the South and Central Western Slopes botanical regions of New South Wales, were assessed to indicate suitable periods of the year to conduct surveys of botanical diversity. The quadrats were located in woodland communities with a generally herbaceous understorey, and subject to a wide range of domestic stock grazing intensities. In the mid to western South Western Slopes (SWS) the greatest number of species was generally recorded in an October survey. The main exception was in degraded areas (low species diversity, high proportion of annual weed species), where similar results were recorded in September and October. In the cooler and wetter eastern SWS a relatively high proportion of species were recorded in October to early December surveys. However, when compared to species totals compiled from multiple assessments in all seasons, or from August to November, a single optimal survey usually recorded only 60–75% of the plant species at a site. Surveys in mid to late summer, autumn and early winter usually recorded less than 50% of the plant species present. The results reflect the prevailing Mediterranean-type climate, and that the ground layer vegetation (primarily comprised of annuals and herbaceous perennials) dominates the species diversity.

Senecio garlandii F. Muell. ex Belcher (Asteraceae) is a perennial subshrub found mainly on rocky outcrops in the South Western Slopes, New South Wales. It is listed as vulnerable in state, national and international listings. An assessment of its conservation status found i) Senecio garlandii has been recorded from about ten localities, ii) it has a relatively large (225 km) north to south distribution from Temora, NSW to Chiltern, Vic., iii) most populations were either within the reserve system (Ulandra, The Rock, Table Top Nature Reserves) or in areas managed for conservation, iv) large populations (> 30,000 individuals) were recorded at The Rock and Table Top Nature Reserves, v) the species appeared capable of regenerating in both the absence and presence of fire, and vi) the populations did not appear to be under direct threat. However, the known localities were highly disjunct and only three localities had substantiated recordings of large populations, while others had very small populations (e.g. < 200 individuals at Ulandra Nature Reserve). In addition, the species was largely restricted to rocky outcrops and on these it was generally restricted to the upper parts of the east- to south-facing talus slopes, often immediately below cliff lines (a small area of occupancy). Application of the IUCN red list criteria would indicate that Senecio garlandii should not be classified as vulnerable. Monitoring is needed to determine whether the populations are in decline or otherwise.

A presence/absence survey of 25 remnant vegetation sites, principally Nature Reserves and State Forests, was carried out in the South Western Slopes (SWS) of New South Wales. A total of 658 taxa were recorded of which 188 (29%) were exotics. Eleven sites had an overstorey dominated by Callitris glaucophylla or Eucalyptus camaldulensis and 14 sites had an overstorey dominated by various eucalypt species such as Eucalyptus blakelyi, Eucalyptus goniocalyx, Eucalyptus macrorhyncha, Eucalyptus polyanthemos, Eucalyptus rossii and Eucalyptus sideroxylon. The Callitris glaucophylla/Eucalyptus camaldulensis dominated sites were in the western half of the region, were flatter and at lower elevation (average minimum and maximum elevations were 191 and 214 m, respectively), were smaller (average area 646 ha), were usually grazed more intensely, had a smaller average number of species per site (151) and a larger average percentage of introduced species (40%). In contrast, the sites dominated by various eucalypt species were usually in the eastern half of the region, had greater relief and were at higher elevation (average minimum and maximum elevations were 294 and 520 m, respectively), were larger (average area 1161 ha), were usually grazed less intensively, had a larger average number of species per site (179) and a smaller average percentage of introduced species (27%). This study provides the first published set of relatively comprehensive species lists for the SWS and has provided information relevant to species distribution, proportion of introduced species in the flora, threatened species, areas of conservation significance and directions for future research.