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Summary: Protecting native biodiversity is a difficult prospect in extremely modified landscapes, especially where high‐impact exotic species are widespread. Using new data and a review of the literature, this paper comments on the use of livestock grazing to manage the invasive and highly combustible pasture grass species, Buffel Grass (Cenchrus ciliaris) and thereby help conserve fire‐sensitive Brigalow (Acacia harpophylla) vegetation in reserves in Queensland, Australia. We cite evidence that shows that grazing is a potentially useful management tool in such cases and its use can be compatible with the protection of both fire‐sensitive vegetation and other native plant species within the understorey. However, there are limitations in implementing grazing within conservation reserves including the lack of a clear understanding of the influence of grazing on biodiversity and resource condition. Importantly, we highlight secondary invasion by the exotic grass Indian Couch (Bothriochloa pertusa) as a key emerging threat that may undermine the biodiversity benefits gained by grazing in reserves. Grazing can be a useful tool for conservation management in particular scenarios, but the associated risks demand accompanying monitoring and reporting of positive and negative impacts to ensure the fundamental aim of biodiversity protection is being achieved. [ABSTRACT FROM AUTHOR]

This paper examines invasion of grasslands on Cape York Peninsula, Australia, by Melaleuca viridiflora and other woody species, and the role of storm-burning (lighting fires after the first wet season rains) in their maintenance. Trends in disturbance features, fuel characteristics, ground layer composition, and woody plants dynamics under combinations of withholding fire and storm-burning over a 3-year period were measured on 19 plots in three landscape settings. Population dynamics of M. viridiflora are described in detail and 20-year population projections based on transition matrices under different fire regimes generated. Numerous M. viridiflora suckers occurred within the grass layer, increasing each year regardless of fire regime, and were rapidly recruited to the canopy in the absence of fire. Storm-burning had little impact on fuel, ground layer or woody plant composition, but maintained open vegetation structure by substantially reducing recruitment of M. viridiflora suckers to the sapling layer, and by reducing the above-grass-layer abundance of several other invasive woody species. Population projections indicated that withholding fire for 20 years could cause a sevenfold increase of M. viridiflora density on Ti-tree flats, and that annual to triennial storm-burning should be effective at maintaining a stable open vegetation structure. These findings argue against vegetation thickening being an inevitable consequence of climate change. We conclude that a fire regime that includes regular storm-burning can be effective for maintaining grasslands and grassy woodlands being invaded by M. viridiflora. [ABSTRACT FROM AUTHOR]