Classifying endangered vegetation communities: a case study of Cumberland Plain Woodlands

Remnants of an endangered community, Cumberland Plain Woodlands on shale, were studied in order to 1) investigate the conflict between the needs of legislation to define parameters of protected communities in a precise manner and the spatial variation in communities, and 2) to define floristic groupings in the Cumberland Plain Woodlands based on all plant species. Sites previously classified as Grey Box Woodland, Grey Box Ironbark Woodland and Spotted Gum Woodland map units were surveyed and compared to the same classification applied by one of the authors. Differences were evident, but both classifications showed statistically significant differences between map units, suggesting that although each classification is valid, the differences between these map units cannot be consistently applied. Canopy species were not useful descriptors of the community as they grouped differently to both the full species list and the understorey species. A significantly different community occurring at the transition between shale and sandstone in Holsworthy Military Area was identified, suggesting the importance of this area to the conservation of variability in communities in this area. The use of multivariate techniques to describe levels of variation in communities is discussed and a potential method for using a standard level of similarity to classify vegetation communities is introduced as a mechanism for defining communities using some consistent technique.