Association of five Austrodanthonia species (family Poaceae) with large and small scale environmental features in central western New South Wales

Twenty-eight natural populations of Wallaby Grasses, Austrodanthonia species, in central western New South Wales were sampled and species presence related to a suite of environmental characteristics. An average of 12 plants were selectively sampled from each population; most populations consisted of at least four out of five species, Austrodanthonia bipartita, A. caespitosa, A. eriantha, A. fulva and A. setacea. Numerous ecological factors allowed the widespread co-occurrence of these closely-related species. Large-scale rainfall and climatic factors were correlated with species-presence but no universal small-scale site environmental variables were important for all species. The most widespread species was Austrodanthonia caespitosa and environmental variations at a local site scale, depending on exposure to solar radiation, may at least partially overcome regional rainfall and climate influences.