Australia is home to a diverse assemblage of plant species that display marked population-level variation in inter-annual flower or seed output (i.e. masting). These include a semelparous bamboo with an estimated inter-crop period of 40–50 years, numerous iteroparous masting gymnosperms, angiosperms that include landscape-dominant eucalypts, arid-zone wattles and spinifex (Triodia spp.) grasses, and a rich selection of species that display disturbance-related forms of masting such as pyrogenic flowering and environmental prediction. Despite the prevalence of masting in the Australian flora, there has been a paucity of research on these plants. Nevertheless, from the literature available, it appears that, similar to other parts of the world, a continuum of inter-year reproductive variability exists, with a small number of species displaying extreme–high inter-annual seeding variability. From experimental studies and many anecdotal reports, most of the fitness benefits associated with masting evident overseas also operate in Australia (e.g. predator satiation, improved pollination efficiency, and environmental prediction). Additionally, some Australian masting species offer periodically important food resources for Aboriginal nations in the form of seed or fruit. These include the bunya pine (Araucaria bidwillii), members of the cycad genera Cycas and Macrozamia, spinifex (Triodia) grasses, and mulga shrubs (Acacia aneura). Key future research areas for effective conservation of Australian masting plants include (1) improved understanding of how management interventions such as burning and silvicultural thinning influence regeneration dynamics and higher-order trophic interactions, (2) further longitudinal monitoring across a range of habitats to identify other, as yet unknown, species that display reproductive intermittency, and (3) elucidation of how changes to temperature, precipitation and fire regimes under climate change will affect reproduction and regeneration dynamics of the Australian masting flora.

• Background and Aims Plant species with fire-triggered germination are common in many fire-prone ecosystems. For such plants, fire timing in relation to the timing of reproduction may strongly influence post-fire population regeneration if: (a) flowering occurs infrequently (e.g. plants are mast seeders); and (b) seed survival rates are low and input from the current year’s flowering therefore contributes a large proportion of the viable dormant seedbank. The role of fire timing in relation to masting as a driver of post-fire recruitment has rarely been examined directly, so this study tested the hypothesis that fires shortly after masting trigger increased recruitment of the obligate-seeding arid zone spinifex, Triodia pungens R. Br., an iteroparous masting grass with smoke-cued germination.

• Methods Phenological monitoring of T. pungens was conducted over 5 years, while a longitudinal seedbank study assessed the influence of seeding events on soil-stored seedbank dynamics. Concurrently, a fire experiment with randomized blocking was undertaken to test whether T. pungens hummocks burnt shortly after masting have greater post-fire recruitment than hummocks burnt when there has not been recent input of seeds.

• Key Results Triodia pungens flowered in all years, though most flowerings were characterized by high rates of flower abortion. A mast flowering with high seed set in 2012 triggered approx. 200-fold increases in seedbank densities, and seedbank densities remained elevated for 24 months after this event. The fire experiment showed significantly higher recruitment around hummocks burnt 6 months after the 2012 mast event than a round hummocks that were burnt but prevented from masting by having inflorescences clipped.

• Conclusions Fires shortly after masting trigger mass recruitment in T. pungens because such fires synchronize an appropriate germination cue (smoke) with periods when seedbank densities are elevated. Interactions between natural fire regimes, seedbank dynamics and fire management prescriptions must be considered carefully when managing fire-sensitive masting plants such as T. pungens.

Large, high-severity wildfires, or "megafires," occur periodically in arid Australian spinifex (Triodia spp.) grasslands after high rainfall periods that trigger fuel accumulation. Proponents of the patch-burn mosaic (PBM) hypothesis suggest that these fires are unprecedented in the modern era and were formerly constrained by Aboriginal patch burning that kept landscape fuel levels low. This assumption deserves scrutiny, as evidence from fire-prone systems globally indicates that weather factors are the primary determinant behind megafire incidence, and that fuel management does not mitigate such fires during periods of climatic extreme. We reviewed explorer's diaries, anthropologist's reports, and remotely sensed data from the Australian Western Desert for evidence of large rainfall-linked fires during the pre-contact period when traditional Aboriginal patch burning was still being practiced. We used only observations that contained empiric estimates of fire sizes. Concurrently, we employed remote rainfall data and the Oceanic Niño Index to relate fire size to likely seasonal conditions at the time the observations were made. Numerous records were found of small fires during periods of average and below-average rainfall conditions, but no evidence of large-scale fires during these times. By contrast, there was strong evidence of large-scale wildfires during a high-rainfall period in the early 1870s, some of which are estimated to have burnt areas up to 700,000 ha. Our literature review also identified several Western Desert Aboriginal mythologies that refer to large-scale conflagrations. As oral traditions sometimes corroborate historic events, these myths may add further evidence that large fires are an inherent feature of spinifex grassland fire regimes. Overall, the results suggest that, contrary to predictions of the PBM hypothesis, traditional Aboriginal burning did not modulate spinifex fire size during periods of extreme-high arid zone rainfall. The mechanism behind this is that plant assemblages in seral spinifex vegetation comprise highly flammable non-spinifex tussock grasses that rapidly accumulate high fuel loads under favorable precipitation conditions. Our finding that fuel management does not prevent megafires under extreme conditions in arid Australia has parallels with the primacy of climatic factors as drivers of megafires in the forests of temperate Australia.

Questions: Buffel grass (Cenchrus ciliaris L.) is a drought-adapted invasive plant that has become a serious environmental weed in many arid and semi-arid systems. This paper examined whether eradication of buffel grass infestations: (i) increases frequency, richness and diversity of native vegetation and seed bank pools; and (ii) improves availability of seed resources for granivores.
Location: Alluvial ironwood/corkwood woodlands in arid central Australia.

Methods: We assessed differences in floristic and seed bank composition between buffel-infested sites and sites where buffel grass had been eradicated ca. 12 years previously. Plant species frequency data from nested-quadrat sampling were amalgamated into plant functional groups to examine their relationship to buffel treatment. A seed flotation method was employed to: (i) assess seed bank composition of functional groups at eradicated vs. infested sites; and (ii) test whether the mass of seeds available for granivores was higher at buffel-free sites.

Results: Buffel-eradicated sites supported richer and more diverse vegetation and seed banks across all functional groups except perennial grasses. The effect was strongest for perennial forbs, annual/short-lived forbs, and annual/short-lived grasses. The overall mass of seeds of non-buffel grass species was ca. 10-fold higher at buffel-removed sites. Numbers of seeds of species in the 0.001-0.009 9 g and 0.000 1-0.000 99 g size classes, both of which contain species with seeds consumed by granivores, were ca. 20- and 14-fold higher respectively at buffel-removed sites.

Conclusions: Buffel grass removal at localised scales provides islands of habitat with improved opportunities for native plant re-establishment and abundant foraging resources for granivores. Future research must disentangle the relative importance of dispersal vs. residual seed banks for community restoration after buffel grass invasion. Extended delays in eradication could allow seed bank reserves to deteriorate to a state that no longer permits regeneration.