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Abstract: Lack of eucalypt recruitment is a key factor in the decline of forest and woodland remnants in low rainfall agricultural regions in Australia. Key to effective management of these forests is an understanding of the requirements and conditions that promote seed germination and seedling establishment (recruitment niche) and the persistence of lignotuberous sprouts (juvenile persistence niche). Recruitment is limited by the availability of safe microsites that are suitable for the germination and establishment of seedlings. The objective of this study was to investigate the microsites of established eucalypt seedlings and lignotuberous sprouts in healthy dry forests burnt in the previous 2–6years in the Tasmanian Midlands. The recruitment niche differed significantly to the juvenile persistence niche while the juvenile persistence niche had characteristics similar to the general forest floor. Seedling microsites were characterised by: canopy gaps and ashbeds (95% of seedlings surveyed); a predominantly northerly aspect (75% of microsites); over 220° shelter with the average distance from a sheltering object being less than 30cm and 80% of seedlings being sheltered by coarse woody debris; soil that was significantly softer (3.8 vs. 5.0kgf/m2) and less water repellent (moderate vs. severe repellency) than the forest floor; and low cover of grass. These characteristics of seedling safe sites all affect moisture availability. Our results have important implications for the management of dry forest in order to facilitate eucalypt recruitment and persistence, suggesting the need for retention of coarse woody debris and the judicious use of fire. [Copyright &y& Elsevier]

Summary 1. Australia's savannas typically are burnt every 1–3 years. Although there are concerns about the effect of frequent fire on recruitment of Australian savanna species, there is a lack of information. This research aimed to determine whether seed or microsite availability limits seedling recruitment of the overstorey tree Eucalyptus miniata and the midstorey shrub Acacia oncinocarpa , whether seed or microsite availability is affected by frequent fire, and the consequent effect on seedling recruitment. 2. Quadrats were established in unburnt areas. Experimental manipulations were addition of seed and/or disturbance of the soil surface to increase the number of microsites suitable for germination. In a second experiment, seed was added to quadrats established in three fire regimes after the annual burning event (unburnt, burnt early in the dry season, burnt late in the dry season). 3. In unburnt areas, seedling regeneration was limited by both seed supply and microsite availability. Both burning regimes reduced seedling emergence, possibly because the reduced canopy cover caused unfavourable microclimate, the increased grass and forb ground cover increased competition for resources, and there was increased loss of seed to seed harvesters. 4. The results indicate that sexual regeneration of these common species is disadvantaged by current burning practices because both seed supply and the number of microsites are reduced. Thus, long-term changes in savanna floristic structure seem likely unless fire managers aim to increase the fire-free intervals. The relative abundance of species able to reproduce vegetatively may increase under frequent fire regimes. Such a change may take a long time to detect given the fire-resistant and long-lived nature of overstorey species, and the capacity for vegetative regeneration in many savanna species. The impacts of fire on limiting seedling regeneration will require savanna managers to consider fire-free intervals... [ABSTRACT FROM AUTHOR]