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Many plants in fire-prone ecosystems produce seeds that are cued to germinate after fire. However, fire is not uniform in the landscape, and there are often refugia where fire does not reach, like rocky outcrops or moist valleys. Erica coccinea, a heath shrub from the South African fynbos, has two distinct pyrophyte forms (a resprouter and a seeder) as well as a ‘pyrofuge’ form that only occurs in fire refugia. We measured germination response to smoke and incubation temperature in seeds from pyrophyte (resprouter and seeder) and pyrofuge populations to determine whether these forms responded differently to a fire-cue (smoke) and a general germination cue (temperature). We found that seeds from pyrofuge plants had high germination success (80.9–92.0%) at the lowest incubation temperature (15/8°C 12h day/night cycle) regardless of smoke exposure. In contrast, seeds from pyrophytes (resprouters and seeders) responded strongly to the smoke cue (71.2–95.0%) and were not as limited by temperature. These results show that fire presence and absence is driving divergence of the primary germination cue in Erica coccinea. Given the patchiness of many natural fire regimes worldwide, we expect there may be pyrofuge populations exhibiting a similar divergence of traits in other species and other fire-prone ecosystems.

The montane area of the Tasmanian Wilderness World Heritage Area was recently burnt by large fires ignited by lightning, and such fires are predicted to become more frequent with climate change. The region has a mix of fire-sensitive and fire-tolerant vegetation, but there is little information available on resprouting ability of seedlings of the dominant species of these mosaics. We predicted that seedlings of species found in fire-prone locations would exhibit more post-fire resprouting than seedlings of Gondwanan relictual species, which typically occur in fire-protected locations. To test this hypothesis we compared topkill and resprouting ability of seedlings from five tree species characteristic of the montane vegetation mosaics by exposing them to a propane burner flame for 0, 15, 30, 45 and 60s, simulating a fire intensity of 33 kW m–1. Overall, 93 of 100 flame-exposed plants were topkilled. Topkill was related to duration of flame exposure and seedling size rather than species. By contrast, resprouting of topkilled seedlings was strongly correlated with species rather than seedling size, and was not affected by duration of flame exposure. Contrary to expectations, the rainforest plant Nothofagus cunninghamii was the strongest resprouter, whereas few of the topkilled eucalypt seedlings resprouted. Our study shows the commonly held association between palaeoendemic Gondwanan species and low fire tolerance versus Australian species and high fire tolerance is overly simplistic. We need to better understand fire recovery mechanisms in the Tasmanian flora using a combination of field observation and experimental approaches.

Plant regeneration strategies are commonly dichotomised as ‘resprouter’ v. ‘non-resprouter’, but this fails to recognise that the extent and type of resprouting following fire disturbance vary within species. Here, we report a case of widespread mortality of resprouters following a fire that burnt 98% of an 80-km2 island in Bass Strait, Australia. A field survey, which assessed woody vegetation in 197 plots across the island, showed fire severity ranged from low to high, with crown defoliation occurring across 85% of the island. In total, 1826 of the 1831 woody stems in the burnt plots were top-killed. Only 7.5% resprouted, despite 89% of the stems belonging to species that have the capacity to resprout. Even in species with at least 5% resprouting, only 22% of top-killed stems resprouted. Resprouting rates were maximal (30%) at intermediate fire severity, and only 5 and 8% at the lowest and highest severity classes respectively. Our findings demonstrate the need to understand factors influencing resprouting, and to incorporate these when modelling vegetation recovery after wildfire.

In temperate Australia, wildfires are predicted to be more frequent and severe under climate change. This could lead to marked changes in tree mortality and regeneration in the region’s predominant eucalypt forests, which have been burned repeatedly by extensive wildfires in the period 2003–14. Recent studies have applied alternative stable state models to select ‘fire sensitive’ forest types, but comparable models have not been rigorously examined in relation to the more extensive ‘fire tolerant’ forests in the region. We review the effects of increasing wildfire frequency on tree mortality and regeneration in temperate forests of Victoria, south-eastern Australia, based on the functional traits of the dominant eucalypts: those that are typically killed by wildfire to regenerate from seed (‘obligate seeders’) and those that mostly survive to resprout (‘resprouters’). In Victoria, over 4.3 million ha of eucalypt forest has been burned by wildfire in the last decade (2003–14), roughly equivalent to the cumulative area burned in the previous 50 years (1952–2002; 4.4 million ha). This increased wildfire activity has occurred regardless of several advancements in fire management, and has resulted in over 350 000 ha of eucalypt forest being burned twice or more by wildfire at short (≤11 year) intervals. Historical and recent evidence indicates that recurrent wildfires threaten the persistence of the ‘fire sensitive’ obligate seeder eucalypt forests, which can facilitate a shift to non-forest states if successive fires occur within the trees’ primary juvenile period (1–20 years). Our review also highlights potential for structural and state changes in the ‘fire tolerant’ resprouter forests, particularly if recurrent severe wildfires kill seedlings and increase tree mortality. We present conceptual models of state changes in temperate eucalypt forests with increasing wildfire frequency, and highlight knowledge gaps relating to the development and persistence of alternative states driven by changes in fire regimes.

The vegetation of fire-prone landscapes is influenced by the frequency, severity, seasonality, return interval and stochastic patterning of fire as well as the responses of its component species. An expected increase in fire frequency and severity in association with global warming may result in compositional changes within, and spatial reorganisation of, plant communities; indeed, some plant communities may even face extinction. Vegetation dominated by fire-sensitive species may be most vulnerable to change in fire frequency. A landscape-scale fire in Kosciuszko National Park in 2003 provided an opportunity to compare recovery in vegetation dominated by resprouters and fire-sensitive, obligate seeders. We hypothesised that if plant assemblages had failed to recover after 10 years in terms of species richness and cover they would have been dominated by seeder species pre-fire. After 10 years, two of the six vegetation types investigated had recovered and these were indeed dominated by resprouter species. Two groundwater-dependent vegetation types (one resprouter-dominated and one dominated by fire-sensitive species) were close to recovery. However, the other two types, non-groundwater-dependent shrublands dominated by both seeder and resprouter species, were still far from recovery at that time, with shrub cover reduced and grass cover increased. The likelihood of recovery after 10 years therefore does not appear to be solely a consequence of the regeneration strategies of the dominant species. Post-fire environmental factors (e.g. grazing, disease, climate) may be just as important as regeneration strategies in determining recovery time. Because not all vegetation had recovered after 10 years, prediction of minimum tolerable fire intervals at a landscape scale is impossible at this time. Future fire management needs to be adaptive, taking into account post-fire influences, rather than prescriptive.

This study analyses the effect of successional stage after farmland terrace abandonment on post-fire plant recovery in a Mediterranean landscape. Specific objectives of the study were to (1) compare fuel characteristics and fire severity in three successional stages after farmland abandonment – dry grassland, dense shrubland and pine stands; (2) analyse the effect of pre-fire successional stage and fire severity on vegetation recovery and (3) analyse the relative vulnerability (i.e. potential for ecosystem shift and soil degradation) to wildfires of the successional stages. We assessed 30 abandoned terraces (15 unburned and 15 burned), with diverse successional stages, on the Xortà Range (south-east Spain). Post-fire recovery was measured 1, 4 and 7 years after fire. The successional stages varied in aboveground biomass, litter amount, vertical structure and continuity of plant cover, and flammability. Dry grassland showed the lowest fire severity, whereas no differences in severity were found between shrubland and pine stands. One year after fire, plant cover was inversely related to fire severity; this relationship attenuated with time after fire. Post-fire recovery of pine stands and shrubland led in both cases to shrublands, contributing to landscape homogenisation. The pine stands showed the largest changes in composition due to fire and the lowest post-fire plant recovery – a sign of high vulnerability to fire. This work was supported by the research projects PATTERN (AGCL2008/-05532-C02–01/FOR) and FEEDBACK (CGL2011–30515- C02–01) funded by the Spanish Ministry of Innovation and Science, and the project CASCADE (GA283068), funded by the European Union’s Seventh Framework Programme (FP7/2007–2013).

Understanding the mechanisms underlying the response of different plant functional types to current and projected changes in rainfall is particularly important in drought-prone areas like the Mediterranean. Here, we report the responses of two species with contrasting leaf characteristics and post-fire regeneration strategies (Cistus ladanifer L., malacophyllous, seeder; Erica arborea L., sclerophyllous, resprouter) to a manipulative field experiment that simulated a severe drought (45% reduction of historical average rainfall). We measured monthly changes in relative growth rate (RGR), specific leaf area (SLA), bulk leaf carbon isotope composition (δ13C), predawn water potential (Ψpd), photosynthetic gas exchange, bulk modulus of elasticity and osmotic potential at maximum turgor (π). Temporal (monthly) changes in RGR of C. ladanifer were correlated with all measured leaf traits (except π) and followed Ψpd variation. However, the temporal pattern of RGR in E. arborea was largely unrelated to water availability. SLA monthly variation reflected RGR variation reasonably well in C. ladanifer, but not in E. arborea, in which shoot growth and δ13C increased at the time of maximum water stress in late summer. The relationship between water availability, and RGR and carbon assimilation in C. ladanifer, and the lack of any relationship in E. arborea suggest that the former has an enhanced capacity to harness unpredictable rainfall pulses compared with the latter. These contrasting responses to water availability indicate that the projected changes in rainfall with global warming could alter the competitive ability of these two species, and contribute to changes in plant dominance in Mediterranean shrublands.

Between 1982 and 2008, data were collected on Loranthaceous mistletoes, their hosts and the fire responses of both, in and adjacent to the Pilbara, an arid region in Western Australia where hummock grasslands (dominated by Triodia sp. R.Br., Poaceae) and mulga woodlands (dominated by Acacia aneura Benth., Mimosaceae) are widespread. Hummock grasslands are fire prone and highly flammable. Mulga woodlands are less so, except in an inter-zone where Triodia in the understorey may be sufficiently dense to carry fire. The foliage (and fresh seed) of all mistletoe species was killed if scorched. Moreover, none had any means of long-term, in situ seed-storage. Three fire-survival strategies were observed across the 16 mistletoe taxa. One species (two varieties) was a resprouter. The other 14 were obligate seeders. Post-fire regeneration of those taxa depended on fresh seed being imported and deposited in suitable host canopies by birds. Twelve of them reduced fire risk by varying degrees of host specificity, favouring hosts that grew in fire-sheltered sites. However, two species had very low host specificity and grew on fire-vulnerable hosts in fire-prone hummock grasslands. Their low host specificity increased the likelihood that imported seed would be deposited on suitable hosts. Since pastoral settlement, fire regimes have changed and current regimes are eroding many mistletoe populations. None of the species occurring in the study area is threatened at bioregional or National levels. Nevertheless, the outlook is bleak for mistletoes growing in areas dominated by hummock grasslands, subregional extinction is likely and there are broader implications for biodiversity.

The processes underlying differentiation of seeder and resprouter life histories were explored by studying changes in life history and morphological traits in intraspecific seeder and resprouter populations of the grass Entolasia stricta and shrub Keraudrenia hillii var. hillii from adjoining rock pavement and fringing woodland habitats. Population traits were sampled in the field and studied under controlled conditions in a randomised experimental design with two levels of population/habitat (seeder/rock outcrop and resprouter/woodland) and two levels of fertiliser (low and high). Life history traits reflecting rate of growth, relative allocation of resources to reproductive and vegetative growth and timing of events, as well as a selection of simple morphological traits were recorded. Generalised linear model analysis showed that population had a strong, significant effect on the majority of traits examined, particularly those relating to reproductive output. Many traits were also significantly responsive to nutrient, or induced plasticity, and significant interaction terms were very few. The two species exhibited parallel intraspecific changes in life history between habitats and traits recorded under experimental conditions were similar to those observed in the field. The populations from pavement shrubland produced a more compact shoot system, faster early shoot growth (E. stricta), more numerous flowers and more numerous and lighter seeds. In fringing woodland, both species produced a larger shoot system, slower early shoot growth and fewer and larger seeds. Significant intraspecific differences in population traits and correlation of population with habitat type indicated that the intraspecific seeder-resprouter populations of both species were ecotypes selected by habitat factors, most likely associated with the edaphic environment rather than fire regime variables.

Recent research has shown that the eucalypts of southern Australia have an unusual and apparently fire-adapted epicormic structure. By studying a range of myrtaceous species from northern Australia we hoped to determine if this structure was also present in northern eucalypts. We anatomically examined the epicormic structures from 21 myrtaceous species in 11 genera from the north of the Northern Territory, Australia. An extremely wide diversity of epicormic structures was found, ranging from buds absent, buds at or near the bark surface, to bud-forming meristems in the innermost bark. These Myrtaceae species displayed a far greater variation in epicormic structure than recorded in any other family. This is possibly a reflection of the importance of the resprouter strategy, a long fire history in Australia and the ecological diversification of the Myrtaceae. Nonetheless, all the investigated eucalypts (northern and southern) possessed the same specialised, apparently fire-adapted, epicormic structure. This is remarkably consistent given the taxonomic, geographical and morphological diversity of the eucalypts.

In spite of enormous fire suppression advances in Mediterranean countries, large high-intensity fires are still common. The effects on vegetation structure and composition of fire and fire regime changes at large spatial and temporal scales are poorly known, and landscape simulation models may throw some light in this regard. Thus, we studied how the abundance, richness, and spatial distribution of the different plant types are sensitive to the frequency, extent and spatial distribution of wildfires, using a landscape simulation model (FATELAND). We simulated the dynamics of 10 plant functional types (PFTs) defined as combinations of post-fire persistence strategies and life forms, under the following fire scenarios: No Fire, Suppressed (one large fire every 20 years), Prescribed (small fuel reductions every year), Unmanaged-1 (two small fires every year) and Unmanaged-2 (four small fires every year). The results suggest that the different fire regimes generate different spatial fire-recurrence patterns and changes in the proportion of the dominant species. For instance, with increasing fire recurrence, seeder shrubs (i.e. those recruiting new individuals after fire from persisting seed bank) with early reproduction increased and seeder trees decreased, while little variation was found for resprouters. Fire also increased the spatial aggregation of plants, while PFT richness decreased with increasing fire recurrence. The results suggest patterns of changes similar to those reported in field studies, and thus they provide consistent hypotheses on the possible vegetation changes due to different fire scenarios.

Persistence niches are expected to favour qualitatively different plant life histories compared with regeneration niches. In fire-prone habitats, for example, resprouting plants may be expected to exploit persistence niches, whereas obligate-seeders by definition exploit regeneration niches. Resprouter life histories should be typified by high rates of survival, which may be offset by relatively low rates of growth and reproduction. This combination of characters is expected to result from trade-offs in resource allocation and because the longevity of individual plants should buffer their populations against the effects of recruitment failure. We asked whether two resprouting perennial shrubs, Epacris barbata Melville and Xanthorrhoea resinifera (Sol. Ex Kite) E.C.Nelson & D.J.Bedford, exhibited the life-history character combinations that are expected for species exploiting a persistence niche. We also investigated how a change in habitat suitability caused by the invasion of a root pathogen may limit the ability of these species to occupy persistence niches. Demographic censuses of several years’ duration in two populations of each species yielded estimates of vital rates that were consistent with the life-history profile expected for a persistence niche. Rates of background survival were high and rates of fire-related mortality were low in both species. As expected, these were associated with low rates of growth and seedling establishment, although rates of seed production and viability were relatively high in both species. The importance of survival was confirmed by stochastic population models, which showed that population viability was more sensitive to decreases in survival of mature plants and increases in fire mortality of established plants than to changes in other vital rates. Seedling growth rates were also relatively important in E. barbata. Populations of both species that had been infected by root rot disease, Phytophthora cinnamomi, had substantially reduced survival rates and, consequently, reduced population viability. These effects were more extreme in E. barbata than in X. resinifera. We conclude that processes that reduce survival, such as disease infection and habitat loss, rather than processes that impede seed production and recruitment mediate the persistence niche. However, we discuss the possibility that this dependency might be mitigated by high fecundity if infrequent conditions that permit large recruitment events have so far eluded detection.

A survey of regenerative strategies in the eucalypts, including lignotuber development, was undertaken by extensive field observations, seedling trials and trials of cultivated individuals over a 12-year period. Four broad regenerative strategies were identified, viz. obligate seeders, lignotuber sprouters, stem sprouters and combination sprouters. These four regenerative strategies are based on the ability to develop a lignotuber and the regeneration strategy after whole-crown destruction. These regenerative strategies do not wholly correspond to the tree, mallee, mallet, marlock and shrub habit categories commonly applied to eucalypts. The obligate seeders include many more terminal taxa than have been previously documented as mallet taxa, with 78 western obligate seeders (the ‘true’ mallets) and nine eastern obligate seeders listed herein. Obligate seeders do not possess a lignotuber and are killed by crown-destructive events, and as such are relatively short-lived in most natural environments. A further 16 taxa are also known to be non-lignotuberous, but these are capable of producing epicormic regrowth from the trunk following crown destruction and are defined as stem sprouters. The remaining two regenerative strategies include taxa that are both lignotuberous and able to regenerate vegetatively following disturbance events. The persistent and conjecturous mallet–marlock–moort distinction is rejected, this study showing it to be dependent on stand density. Data presented indicate no significant difference in germination time or maturation time between western obligate-seeder taxa and closely related sprouter taxa. The conservation status of obligate-seeder taxa is discussed. Nomenclatural issues regarding the taxonomic distinction between obligate-seeder and resprouter sister taxa are discussed. A census of regenerative strategies for all recognised eucalypt taxa is included as an accessory publication on the web.

Fire is an important ecological factor that influences the distribution and abundance of plant populations of shrub species in fire-prone habitats. Comprehensive information about the fire-response syndromes and post-fire recruitment of seedlings in tableland habitats of eastern Australia is poorly known. In particular, data on shrubs occurring in grassy habitats are lacking for temperate regions of Australia. The post-fire response and recruitment patterns of shrub taxa were recorded from research burns and wildfires on the New England Tablelands over 4 years in the following four habitats: grassy woodlands and open forests, shrubby open forests, wet heaths and rocky outcrops. The ratio of obligate seeder to resprouter species differed among habitats, with the highest ratio occurring on rocky outcrops (90 : 10) and the lowest in grassy forests (19 : 81). Post-fire recruitment of seedlings was also highest on rocky outcrops whereas seedlings were rarely observed in the wet heaths and grassy forests. The following six models that explain these patterns were reviewed: fire and grazing frequency, soil nutrients and texture, habitat openness and environmental variability. No one model could uniformly explain differences in fire response across all habitats but a combination of disturbance-frequency and regeneration-niche models may provide a mechanism for the patterns observed. Field and laboratory experiments are needed to examine allocation to persistence (resprouting) and reproduction in species with different fire-response syndromes. These experiments also need to examine both disturbance-frequency and regeneration-niche factors in manipulative experiments.

The reproductive biology of two species pairs was compared, one member of which (Dryandra sessilis (Knight) Domin, Hakea erinacea Meissner) is susceptible to severe stress and disturbance by fire (nonsprouter) and stores few seeds in its crown, while the other (D. lindleyana Meissner, H. cristata R.Br.) is resilient (resprouter) and also stores most of its seeds for some years. It was hypothesised that the nonsprouter would have a high annual seed production associated with a suite of attributes directed towards that end (forming a reproductive syndrome), and that the resprouter would have the reverse properties. Over 30 attributes were assessed, covering putative pollinators, pollinator attractants and rewards, flower phenology, breeding system, and flower, fruit and seed production. Dryandra sessilis produced far more seeds than D. lindleyana, due to prolific flower production and a high fruit : flower ratio (associated with an effective outcrossing breeding system). Hakea erinacea produced significantly more seeds than H. cristata, which was attributable to its smaller fruits and exceptionally high fruit : flower ratio (associated with highly effective selfing). The correlation of seed production and fruit : flower ratio with susceptibility to fire was not supported by any consistent pattern among the other reproductive attributes.

Pre- and post-dispersal reproductive success was studied in 22 species from three related Southern Hemisphere families, Restionaceae, Ecdeiocoleaceae and Anarthriaceae. Pre-dispersal success was compared for resprouter and obligate seeder species using seed: ovule ratios and carpel: flower ratios. The data indicated a high level of variability between taxa but pre-dispersal reproductive success of obligate seeders was significantly higher (67% conversion of ovules to seeds) than that of resprouters (35%). Two seeders, an extremely rare species (‘Chordifex’ abortivus) and a strongly clonal species (Alexgeorgea subterranea), showed pre-dispersal reproductive success values lower than or equal to the mean value for resprouters. Post-dispersal reproductive success was predicted in terms of proportions of germinable seeds produced per ovule (as determined by in vitro germination of isolated embryos). Data again varied widely between taxa, averaging 23% conversion of ovules to seeds with no clear relationship to regeneration mode. The mean number of germinable seeds per culm ranged from 0.03 to 21 between species, with cases of particularly low ovule output and/or low germinability in critically low germinable seed numbers for a species. The regeneration potential of a subset of species was assessed as mean annual production of germinable seed per reproducing plant of a population. The data indicated low values (less than eight seeds per adult) for all but three highly fecund species, suggesting that germinable seed output in some species might be scarcely able to compensate for natural senescence or catastrophic loss of parent populations (e.g. after fire, disease, increased competition following eutrophication).

The effect of high frequency fire regimes on a coastal heathland north of Sydney was examined. Plant community composition and species frequency and density (of a subset of species) were compared among sites burnt by either one, two or three fires in the period 1988-1990 inclusive. Constrained ordination indicated that number of fires had a significant effect on floristic composition. Site variables also had a significant effect on floristics and frequency and accounted for a larger proportion of variation than did number of fires. Analyses of deviance indicated that frequency in 13 species was unaffected by fire regimes or site factors. Site factors significantly affected frequency in 42 species. Frequency in seven species was significantly affected by fire regimes (no site effect). In six of these, frequency was lower in areas subjected to either two or three fires compared to one fire. Three of these species were obligate seeders. Frequency in the other species (a herbaceous resprouter) was significantly higher in the area subjected to two fires. There was no significant effect of fire on species richness. Densities of seven out of a subset of eight species were also significantly affected by fire (two obligate seeder spp.) and site factors (four spp.), Significantly lower densities were related to multiple fires. The study indicated that regimes of frequent fire can deplete populations of some heathland species with the dominant shrub species, Banksia ericifolia L.f., being most affected.

Recruiting populations of seeder (Astroloma xerophyllum (DC.) Sond. and Leucopogon conostephioides DC.) and resprouter (Leucopogon verticillatus R.Br. and Conostephium pendulum. Benth.) epacrids were examined over an 8 year period, using time of fire, shoot morphology and root xylem ring number to age plants. The seeders commenced flowering earlier, achieved three-fold higher shoot:root ratios but accumulated much smaller root starch reserves than the resprouters. The resprouting potential of L. verticillatus was 'bud initiation-limited', since progressive shoot removal exhausted the bud-producing potential but did not fully deplete the starch reserves of the root stock. Apparent conversion efficiency of starch to new shoot biomass was 88%. The corresponding response in C. pendulum was 'energy reserve-limited', with shoot removal eliminating root starch but leaving many unexpanded buds. Dendroecological analyses of root xylem growth rings were undertaken on 15 year-old plants of C. pendulum recruiting from seed in unburnt and adjacent periodically burnt habitats. Growth ring extension of burnt plants resumed after each fire at rates faster than their unburnt counterparts, suggesting that improved access by resprouting shoots to light, water and nutrients compensated for destruction of the previous shoot system.

The genus Hakea Schrader (Proteaceae) has its world centre of diversity in south-western Australia; the majority (c. 70%) of species are endemic to this region. To examine the distribution of Hakea within south-western Australia, canonical correspondence analysis (CCA) was used on species presence and bioclimatic parameters in 0.5° x0.5° latitude-longitude grid cells. Of the 12 bioclimatic attributes initially applied, annual temperature and rainfall data, and indices of their variation, were best related to species distribution. Clustering of the species (on the CCA ordination) produced five distinct groups (not including species near the origin of the ordination) roughly representing floristic regions of southwestern Australia (Avon, Irwin, Eyre-Roe, southern Darling, northern-central Darling). Species distribution was then related to four morphological groups based on their leaf type (broad, terete) and post-fire life form (non-sprouter, resprouter). The highest percentage of terete-leaved non-sprouters occurred in areas of low-moderate rainfall and large annual temperature ranges (Avon and Eyre-Roe clusters), whereas terete-leaved resprouters displayed a very patchy distribution, accounting for less than 20% of the hakeas present in most of the grid cells. Broad-leaved resprouters dominated areas of strongly seasonal rainfall (Irwin and northern-central Darling clusters), with few species occurring in the drier Avon and Eyre-Roe districts. Broad-leaved non-sprouters were best represented in areas of low annual temperature (southern Darling and Eyre-Roe clusters). The distribution of non-sprouters and resprouters may be due to climatic factors affecting seedling recruitment and/or fire frequencies. Leaf morphology appears to be more directly related to species distribution, as broad leaves are favoured in regions of medium-high, seasonal rainfall (less stressful habitats) while terete leaves are better adapted to tolerate hot, dry environments.

Banksia includes 38 fire-killed (seeders) and 20 resprouting species, and two species with contrasting ecotypes, in south-western Australia. There may be up to 12 seeders per 50 × 50 km grid cell in the southern sandplains and 12 resprouters in the northern sandplains. The patterns of distribution of species across soil type and eight climatic attributes is similar for both life forms, except that greater numbers of resprouting species occur at higher rainfalls and where there is greater seasonal spread of rainfall. Most seeders occur on white sands and rocky substrates, and resprouters occur on yellow sands and the more fertile lateritic soils. Nutrient requirements for both life forms appear to be similar. Resprouters are more widespread than seeders which suggests that resprouters show greater environmental tolerances. The distribution of grid cells containing each life form across soil types and eight climatic attributes is similar and any differences in climatic profile for all species in each category are considered biologically insignificant. Both life forms in section Abietinae are well represented in the climatically distinct southern and northern sandplains indicating no climatic preferences within the lineage. There are no consistent trends in environmental attributes from fire-killed to resprouting ecotypes of B. ashbyi E.G.Baker and B. violacea C.A. Gardner. Multiple-partitioning classification of the floristic data produced 10 groups varying greatly in geography, species richness, and proportion and endemism of each life form. The Lesueur (northern) district has four endemic seeders, six endemic resprouters and a mean of 10 resprouters per cell. The East Eyre (southern) district has five endemic seeders, no endemic resprouters and one resprouter per cell. Both groups have a mean growing season of 5 months. The relative aridities and fluctuations of present and past (Quaternary and late Tertiary) climates are invoked to explain the much higher proportion of resprouters in the northern than southern sandplains and the absence of seeders in the most marginal cells. The absence of endemic species yet high proportion of resprouters (73%) in the extreme south-western corner of the region might be explained by elimination of seeders through frequent burning by Aborigines in the late Quaternary. The increase in the proportion of fire-killed species along the south coast from 23% to 100% at the edge of the Nullarbor Plain also requires an explanation.

Study of Lyginia barbata across its distribution range in south-western Australia identified five distinctive morphotypes, viz. a tall-culmed, densely tufted fire-sensitive obligate seeder (S morphotype), a tall densely tufted fire-resistant resprouter (R1), a short flexuose-culmed, tufted resprouter (R2), a weakly clonal, semi-tufted resprouter (R3) and a short-culmed, widely spreading clonal form (R4). There was little variation within a morphotype between habitat locations and no evidence of intergrading of cohabiting morphotypes. Morphotype-specific differences were observed in culm height, rhizome morphology, culm density and spikelet morphology. Differences in reproductive biology related to the time of first reproduction in juvenile recruits, spikelet number per male and female culm, ovule number per female culm and seed : ovule ratio. Differences of a physiological nature were observed in seedling growth rates and proportional biomass (dry matter) allocations to culms, rhizomes, spikelets and seeds. Comparative quantitative scorings of the above features according to concepts of r- and K-selection rated the S form strongly r-selected, the R4 form equally strongly K-selected and the other forms (R1, R2 and R3) intermediate and with the R1 form possibly more r-selected than the others. It is suggested that the data provide a basis on which future taxonomic decisions regarding the taxon might be made.

Populations of south-western Australian members of the Restionaceae were examined in a wide range of wetland, seasonally inundated and dryland habitats over 4 years and the behaviour of 82 of the species authenticated according to whether they survived (resprouter strategy) or were killed (obligate seeder strategy) by fire. Material of the same seeder and resprouter species collected during summer or early autumn from habitats not burnt for at least 5 years was then used for morphometric measurements, observations on rhizome morphology, determinations of culm: rhizome dry weight (DW) ratios and assays of starch and sugars in rhizomes. Rhizome diameters of all 37 resprouters exceeded 2.3 mm while 28 of the 45 seeder species had narrow rhizomes in the range 0.2-2.1 mm. Culm : rhizome DW ratios of seeders (mean 12.3 ± s.e. 1.2) were much higher than those of resprouters (mean 2.9 ± s.e. 0.4). Mean ± position of perennating buds of seeders was mostly at or close to soil surface (-0.6 ± 0.2 cm), while that of resprouters was more deeply buried ( 2.8 ± s.e. 0.5 cm), Seven categories of rhizome morphology were recognised. Three of these (essentially tufted habit, rhizome growth ascending or erect) were much more typical of seeders (n = 37) than resprouters (n = 5). The other four categories included rhizomes of basically horizontal growth and a loosely tufted or widely spreading habit, and were collectively associated more with resprouters (n = 32) than seeders (n = 8). Starch was present at detectable levels in rhizomes of 23 species of resprouters (mean concentration ± s.e. DW for these positive species was 7.13 ± 1.62%) and only 3 seeders (0.16 ± 0.11%). Levels of total soluble sugars (mean ± s.e. DW) (predominantly sucrose, fructose and glucose) were 3.39 ± 0.59% in resprouters compared with 1.06 ± 0.19% in seeders. Data are discussed in relation to previous studies on seeder and resprouter representatives from other plant families.

The heathland form of Banksia marginata Cav. regenerates rarely from seed but commonly by resprout- ing from buds on lateral roots, whereas Banksia ornata F. Muell. regenerates only from seed, usually released after fire. The two species co-occur in heath vegetation on nutrient-poor soils in south-eastern South Australia and western Victoria. Shoots were sampled from stands of B. marginata aged from 1 to 25 years and of B. ornata aged from 1 to 50+ years after fire in the Little Desert National Park, western Victoria. B. marginata, the resprouter, distributed a greater proportion of the total shoot dry matter and content of all nutrients to vegetative growth over its shorter life span than B. ornata, the non-sprouter. About 50% of the total phosphorus in B. ornata shoots at 50+ years was present in cones (including seeds) compared with only about 20% in B. marginata shoots at a comparable stage of senescence (25 years). This difference between the species was also true to a lesser degree for nitrogen. There were considerable differences between other nutrients in their distribution patterns in shoots. Nutrients could be grouped together on the basis of distribution in shoots more satisfactorily than on presumed physio- logical roles. Stems were major sites of nutrient accumulation in both species. The content of a particular nutrient in seeds as a proportion of the content in the living parts of the shoot ranged from 0.03% (Na, Mn) to 2.0% (P) in B. marginata, and from 0.3% (Na) to as high as 31% (P) in B. ornata. Concen- trations of all nutrients except sodium were much higher in seeds than in the woody cones or vegetative organs of both species; seeds of B. ornata were particularly rich in calcium and manganese. We conclude that the different patterns of distribution of biomass and nutrients, especially nitrogen and phosphorus, within shoots of the two species reflect their different regenerative modes after fire. Introduction Phosphorus and, to a lesser extent, nitrogen limit the growth of sclerophyllous shrubs on nutrient-poor soils in southern Australia

A study was made of both natural and cultivated populations of the resprouter after fire, Leucospermum cuneiforme, and two non-sprouters, L. cordifolium and L. erubescens. Measurements included florets per head, heads per plant (on an absolute and volume basis), nectar volume and sugar concentration, seeds per head and seed set following bagging to prevent access to pollinators. The results provided almost no support for the hypothesis that, in comparison with non-sprouters, resprouters minimize their reproductive effort in association with self-incompatibility. There was, however, some support for earlier proposals that the most self-compatible species (in this case, L. cuneiforme) have the widest ecological range, the greatest reproductive effort and highest percentage seed set.