Native Grasslands of the Central Highlands, Queensland, Australia. Floristics, Regional Context and Conservation.

Abstract

A floristic classification of grassland and related woodland vegetation from the Central Highlands of Queensland suggests four broad types: Mountain coolibah (Eucalyptus orgadophila) woodland on basalt, Mitchell grassland (dominated by Astrebla lappacea) on alluvia and two closely related groups dominated by Dichanthium sericeum, Blue grassland on basalt and Blue grassland on sediment. An analysis including floristic data from grassland and woodland on vertosols from throughout southern, central and western Queensland revealed that the Blue grasslands of the Central Highlands are highly dissimilar from other grasslands in Queensland. Mountain coolibah woodland on basalt is represented within four reserves, but the other more arable grassland types are either not represented or only barely represented within the reserve system. The most immediate threatening process to these communities is conversion to crops and this process is exacerbated by the difficulties of managing the grasslands as native pasture. Large areas of grasslands are degraded, having been converted from dominance by native perennial grasses to the unpalatable, annual, exotic herb Partheniunz hysterophorus. Once this shift has occurred a long period with little or no production benefits is required to recover a sward of native perennial grasses and the cropping alternative becomes particularly favourable. The long-term security of the native grasslands of the Central Highlands will require an enhanced reserve system and incentives designed to retain appropriately managed native pasture. Key words: grassland, grazing, reserves, woodland. Queensland, exotics, Parthenium