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Ecological response syndromes in the Flora of Southwestern Western Australia: Fire resprouters versus reseeders.

18 Dic 2015 
I. Abstract

Two fire-response syndromes can be described for species of the vegetation of Mediterranean-climate, southwestern Western Australia. Resprouters survive fires as individuals. Reseeders are killed by fire and must reestablish through germination and establishment of seedlings. Of the Western Australian plant families analyzed for fire-response strategies, 50% of the Proteaceae, 50% of the Restionaceae, 45% of the Orchidaceae, and 25% of the Epacridaceae are resprouter species. Within genera of the Proteaceae, the proportions of resprouters include Adenanthos (56%), Hakea (52%), Dryandra (35%), and Grevillea (31%). Within Banksia, 49% are resprouters, and it appears that the reseeding syndrome is the derived character in this genus. The proportion of resprouters within southwestern Western Australian plant communities ranges from 66% to 80%. These percentages are generally higher than in more arid parts of Western Australia and in comparable plant communities from other Mediterranean-type climates of the world. The relatively high proportion of resprouters within plant families and within plant communities probably indicates that the Western Australian vegetation experiences a harsher fire stress regime than do other Mediterranean-type climate areas. Western Australian plant communities have their highest diversity in the early years after fire, when the vegetation contains a higher number of reseeding species and individuals. Seed banks are dominated by the seeds of reseeders.

There are no basic differences in mean seed mass, viability, orgerminability of seeds between resprouting species and reseedingspecies, but reseeders tend to have narrower optimum germinationtemperature regimes. Establishment success is related more to seed mass,seedling size, and leaf ecophysiology and morphology than tofire-response strategy. Reseeder seedlings tend to grow faster than doresprouter seedlings. Basic shrub morphology differs, with reseedersgenerally being umbrella shaped and resprouters urn shaped. Reseedingspecies most commonly have a shallow, fibrous root system. Resproutershave a massive, deeply penetrating root system. Shoot:root ratios offirst-year seedlings and mature plants are higher for reseeders.Resprouter seedlings store starch in root tissue at a much greater ratethan do reseeder seedlings. Although the concentrations of essentialnutrients in seedlings are not different between fire-response types,reseeders tend to conserve nutrients to a greater extent through leafretention. Reseeders tend to produce greater numbers of flowers andgreater amounts of floral rewards, but the breeding systems, which leadto the higher seed set in reseeders, can vary between strict outcrossingand considerable selfing. Reseeding species are not likely to be windpollinated. Species survival in a fire-prone environment can involve awide range of combinations of attributes. It appears that in WesternAustralian reseeder species the lack of an ability to resprout iscompensated for by a number of other structural and functional features.

Knowledge of the fire-response strategies of species of southwestern Western Australia can influence fire-regime management, conservation of rare species, and restoration of vegetation after disturbance. Further knowledge of the fire-response strategies of species of the southwestern Western Australian flora should result in better management of natural and restored plant communities of the region.


Es konnen zwei Syndrome in bezug auf Waldbrande fur Vegetationsarten des mediterranen Klimas im Sudwesten Westaustraliens beschrieben werden. Pflanzen, die nach dem Waldbrand wieder austreiben, songenannte "resprouter," uberleben als Individuen. Pflanzen, die vom Feuer vernichtet werden, mussen sich durch Keimung der Samen und des Aufwachsens der Samlinge neu etablieren (sogenannte "reseeder"). Eine Analyse der Strategien als Reaktion auf Waldbrande ergab fur Pflanzenarten in Westaustralien, da[beta] 50% der Proteaceae, 50% der Restionaceae, 45% der Orchidaceae, und 25% der Epacridaceae "resproter" sind. Innerhalb der Familie der Proteaceae sind Pflanzen, die wieder austreiben, antelismaBig zu 56% in Adenanthos, zu 52% in Hakea, zu 35% in Dryandra, und zu 31% in Grevillea vertreten. 49% der Banksia Arten sind "resprouter," und es erscheint, da[beta] das Syndrom der Wiederausbreitung durch Samen em abgeleitetes Merkmal in deiser Familie ist. Der Anteil der "resprouter" betragt in Pflanzengemeinschaften im Sud weten Westaustraliens 66 bis 80%. Diese prozentualen Anteile sind im allgemeinen hoher als in mehr wustenahnlichen Gebieten Westaustraliens und in vergleichbaren Pflanzengemeinschaften anderer mediterraner Klimate. Der relativ hohe Anteil von "resprouter" innerhalb Pflanzenfamilien un Pflanzengemeinschaften ist wahrscheinlich em Anzeichen dafur, da[beta] die Vegetation in Westaustralien starker von der Einwirkung des Feuers gepragt ist als andere Gebiete mediterranen Klimas.

Westaustralische Pflanzengemeinschaften haben ihren hochsten Gradan Vielfalt in fruhen Jahren nach einem Waldbrand, wenn die Vegetationein hohe Anzahl von Pflanzenarten und Individuen enthalt, die"reseeder" sind. Samenbanken dominieren durch Samen von"reseeder."

Es gibt keine grundlegenden Unterschiede zwischen "resprouter"- und "reseeder"-Pflanzen in bezug auf mittlerer Samenmasse, Uberlebensfahigkeit oder Keimfahigkeit der Samen. Allerdings neigen die Samen der "reseeder"-Pflanzen zu einem engeren Temperaturoptimum wahren der Keimung. Der Erfolg der Landbesiedelung hangt vornehmlich von Samenmasse, SamlingsgroBe und B1attokophysiologie und Morphologie ab und weniger von der Strategie als Reaktion auf Waldbrande. Samlinge von "reseeder"-Pflanzen wachsen in der Regel schneller als Samlinge von "resprouter"-Pflanzen. Die grundlegende Buschmorphologie unterscheidet sich im allgemeinen zwischen "reseeder"-Pflanzen, die eine Regenschirmform, und "resprouter"-Pflanzen, die eine Vasenform annebmen. 'Reseeder"-Pflanzenarten besitzen zumeist ein flaches, fibriliares Wurzelsystem. "Resprouter"-Pflanzen besitzen ein massives, tief durchdringendes Wurzelsystem. Trieb: Wurzel-Verhaltnisse von einjahrigen Samlingen und ausgewachsenen Pflanzen sind hoher fur "reseeder"-Pflanzen. "Resprouter"-Samlinge speichern Starke im Wurzelgewebe in hoherem MaBe als "reseeder"-Samlinge. Obwohl essentielle Nahrstoffkonzentrationen in Samlingen nicht differieren zwischen "reseeder" und "resprouter," konservieren "reseeder"-Pflanzen, Nahrstoffe in groBerem AusmafB durch Blatterhalt. "Reseeder"-Pflanzen neigen zu einer erhohten Produktion der Blutenanzahl und einer groBeren Menge von bestaubten Bluten. Zuchtungssysteme hingenen, die zu einer hoheren Samenanlage in "reseeder"-Planzen fuhren, konnen zwischen strikter Fremdbestaubung und betrachtlicher Selbstbestaubung variieren. Es ist unwahrscheinlich, daB "reseeder"-Pflanzenarten vom Wind bestaubt werden. Das Uberleben von Pflanzenarten in einer von Waldbranden gepragten Umwelt kann eine Reihe von Kombinationen von Attributen einschleiBen. Es erscheint, daB in westaustralischen "reseeder"-Pflanzenarten der Mangel an der Unfahigkeit, neu auszutreiben, durch eine Anzahl anderer struktureller und funktioneller Merkmale kompensert wird.

Kenntnisse der Strategien von Pflanzen im Sudwesten Westaustraliens gegen Waldbrande konnen das Feuermanagement Regime, die Erhaltung seltener Arten und die Erneuerung der Vegetation nach einer Storung beeinflussen. Zusalzliche Kenntnisse der Strategien gegen Waldenbrande von Arten in der sudwest-/westaustralisehen Flora sollen zu besserem Umgang mit naturlichen und erneuerten Pflanzengemeinschaften der Region fuhren.

II. Introduction

The Southwest Botanical Province of Western Australia is a 310,000 [km.sup.2] region of forests, woodlands, and shrublands (kwongan) in a Mediterranean-type climate (Beard, 1990). Repeated fires, usually following the summer drought, have had a marked influence on the vegetation, eliminating intolerant species and encouraging the spread of fire-resistant species. Palaeontological evidence indicates that lightning-induced fires have occurred frequently in southwestern Western Australia for at least the past 5,000 years (Churchill, 1968; Hassell, 2001). Therefore, even at a conservative fire interval of 20 years, any given site has experienced 250 wildfires. In adapting to this environmental pressure, current members of the flora show a variety of adaptive traits to maintain a presence in the postfire community. Two major fire-response syndromes are apparent: resprouters and reseeders. Resprouting species are those species whose postfire presence depends predominantly on individual survival. Individuals of res eeding species die as a result of the fire, and their continued presence in the post-fire community depends on establishment of a new generation of seedlings from soil-stored or canopy-stored seeds.

In reality, resprouters and reseeders represent the ends of a continuum of fire-response strategies (Keeley & Zedler, 1978; Benwell, 1998), much as the r-K dichotomy is a continuum of life-history characteristics in response to overall environmental stress (MacArthur & Wilson, 1967). Gill (1984) classifies woody plant species in relation to their response to fires, with a major dichotomy related to whether reproductively mature plants with 100% leaf scorch die or survive. Subclasses of those that survive--the resprouters--include those with either subterranean (Koch & Bell, 1980) or aerial regenerative buds (Gill, 1984). Severely burned aerial resprouters, however, may survive through epicormic buds from underground tissue. The terms "obligate vegetatively reproducing sprouter," "autoregenerating long-lived sprouter," and "facultative sprouter-seeder" have been used to divide resprouters into subclasses in relation to the number of postfire seedlings that are produced (Keeley & Zedler, 1978; Bell et al., 198 4; Gill & Bradstock, 1992). Reseeders (also called "nonsprouters," "seeders," and "obligate reseeders") can also be variously divided into monocarpic ephemerals, polycarpic ephemerals, herbaceous perennials, and woody plants. Ephemerals may also include species that germinate and establish annually with or without a fire (usually therophytes) or those that germinate only because of cues resulting directly from burned vegetation (fire ephemerals or fire weeds) (Pate et al., 1985). In this review, however, I have chosen to accept the most basic of divisions and to delve into aspects of their respective abilities to cope with fire in the natural environment of southwestern Western Australia.

III. Genetic Patterns

Comparisons within plant families for particular ecological traits can provide information on how species have evolved under differing environmental stresses. Brown and Maurer (1987) introduced the concept of macroecology, in which individual species function as replicates in the search for relationships between evolutionary diversity and ecological traits. The Southwest Botanical Province is renowned for its speciation and endemism (Hopper, 1979). By restricting the geographical area of consideration and constraining the phylogeny, it is more likely that a certain trait may correlate more directly with any particular environmental condition (Westoby et al., 1995). In the Western Australian flora, 25% of the 92 species of Epacridaceae are resprouters (Bell, 1995) (Table I), whereas the proportion of resprouters in the Orchidaceae is 45% (Dixon, 1991). These two families are relatively advanced plant families (Sporne, 1974). In the more primitive Proteaceae family, the proportion of resprouters is 50% (Bowen, 1991), but the proportion in the more advanced Restionaceae is also 50% (Meney, 1993). Detailed analysis of the postfire-regeneration trait has also been undertaken within the particular genera of the Proteaceae (Lamont et al., 1985a; Cowling & Lamont, 1998). Of the genera examined in detail, the proportions of resprouting members of the proteaceous genera of Western Australia are Adenanthos (56%), Banksia (49%), Dryandra (35%), Grevillea (31%), and Hakea (52%).

Within Banksia in Western Australia, there are greater numbers of resprouters in higher rainfall areas and where there is greater seasonal spread of rainfall (Lamont & Markey, 1995). The very low numbers of reseeding banksias in the moist forest zones of southwestern Western Australia may be partially attributable to the long history of burning by Aboriginal Australians (Lamont & Markey, 1995). Comparative resprouter percentages of proteaceous genera in the South African fynbos appear lower, which may be an indication that the Australian environment is a more fire-prone environment than are the Mediterranean-climate areas of southern Africa. Only in Banksia has it been determined which fire-response syndrome is the derived character; somewhat surprisingly, the reseeding Banksia species seem to be the more modern (George, 1981).

Within some species, particular populations act as postfire resprouters, whereas others act as postfire reseeders. This is true of Banksia violacca (A. S. George, pers. comm.). In Lyginea barbata, there are also some populations that resprout after fire and others in which all adults are killed (Pate et al., 1991). As with species within genera, there is presently no indication of which population is the more modem.

IV. Synecological Patterns

Fires are a natural part of the environment of the vegetation of southwestern Western Australia, and all communities contain a mix of resprouters and reseeders (Table II). In the forest-dominated communities of the southwest, resprouting species represent about 69-75% of the flora (Christensen & Kimber, 1975; Bell & Koch, 1980; Burrows et al., 1995). The more arid, shrub-dominated kwongan ecosystems of the Northern Sandplain have approximately 66%-74% resprouters (Bell et al., 1984; Bell & Loneragan, 1985; van der Moezel et al., 1987b). The shrublands of the southern coastline in Western Australia have about equal percentages of resprouters and reseeders (Hassell, 2001). Comparable heath-dominated habitats in the eastern Australian states have between 70-80% resprouters (Specht et al., 1958; Siddiqi et al., 1976; Russell & Parsons, 1978). By comparison, inland, semi-arid mallee regions in Western Australia have only about 23% resprouters in the flora (van der Moezel & Bell, 1984), and the sand-dune-and-clay-s wale vegetation of the Great Sandy Desert has about 25% (Goble-Garratt, 1987). A similar gradient involving a reduction in the percentage of resprouters in the flora with increasing aridity has also been noted in California chaparral vegetation (Keeley, 1986).

Fire frequency influences the proportions of resprouters and reseeders in plant communities. Keeley and Zedler (1978) hypothesize that short intervals between fires promote the success of resprouters. Rapid recovery after fire and the immediate capacity to outgrow and outcompete establishing seedlings gives a distinct competitive advantage to resprouters. Resprouters would be likely to have the biomass necessary to produce seed crops at an earlier age than would a competing reseeder. Resprouter species tend also to be resilient to even highly frequent burning and, therefore, do not have the risk of localized extinction as do reseeders.

Conversely, a long interval between fires favors the reseeding strategy (Keeley & Zedler, 1978). With increasing time between fires, fuel loads tend to accumulate, and the size of individuals increases with progressive self-thinning. Fires in such long-unburned areas would be more intense, resulting in a greater likelihood of the deaths of individual resprouters, as well as all reseeder individuals. Also, the size of the postfire openings may be expected to increase with longer intervals between fires (Frost, 1984). In this situation, nutrient release following fire may be great, and the rapid growth rate of recruits within the relatively larger clearings may mean that reseeder species will eventually outcompete slower-growing resprouter seedlings. The second advantage of the reseeder strategy is that individuals in some cases reproduce sexually at an earlier age and produce larger seed stores, thereby maximizing the genetic heterogeneity of their offspring. Variability in the postfire environment following d ifferent fires means that selection pressures will vary and that there would be an advantage to maximizing genotypic variation.

The proportion of resprouters in the vegetation of the other Mediterranean-type climate regions is generally less than that found in southwestern Western Australia. In California chaparral the resprouter percentage is 44-50% (Hanes, 1971); in the Cape Region of South Africa, less than 50% (Kruger, 1979; Milewski, 1983; Lamont et al., 1985b). The Mediterranean maquis and garrigue, and the Chilean mattoral, are clearly unlike the vegetation of the other Mediterranean-type climates in the near lack of the reseeding mode in the dominant evergreen shrub vegetation (Naveh, 1974; Keeley & Johnson, 1977). It is possible that anthropogenic fires have eliminated reseeders from the vegetation around the Mediterranean Sea (Naveh, 1984). The lack of reseeding species in Chilean vegetation, on the other hand, may be an indication that wildfires have been an uncommon part of the evolutionary pressures in this region (Mooney, 1977). The very large community proportion of resprouters in the southwestern Western Australian veg etation (66-75%) indicates that the Australian fire interval is probably much shorter than the fire interval in the other Mediterranean-climate regions.

In Western Australian plant communities, species diversity is greatest shortly after fires, when the vegetation simultaneously contains both resprouting and reseeding species (Bell & Koch, 1980; Fox & Fox, 1986). An initial postfire increase in community species richness and diversity followed by a gradual decline is the typical pattern in most of the world's fire-prone, Mediterranean-climate ecosystems (Adamson, 1935; Specht et al., 1958; McPherson & Muller, 1969; Vogl & Schorr, 1972; Russell & Parsons, 1978; Kruger, 1983). The decline in species richness and diversity is predominantly a decline in living representatives, because, over time, more and more of the reseeding species senesce and are then represented in the region only as seed. Fire succession in Western Australian plant communities generally follows the initial floristic composition model (Noble & Slatyer, 1981), with a full complement of the flora represented as aboveground living individuals at the beginning of the fire interval and a mix of l ive individuals and quiescent seeds at the end of a fire cycle. Resprouter species populations in Australian communities are multi-aged, with cohorts of seedlings surviving only if germinated early in the interfire interval (Bradstock & Myerscough, 1981; Zammit & Westoby, I 987a, I 987b). Populations of reseeders, on the other hand, are nearly always even- and single-aged (Cowling et al., 1987).

The high proportion of resprouters in the southwestern Western Australian plant communities, also means that postfire plant cover and biomass recovery is very rapid, with a leveling off of these community attributes after only 5-10 years (Bell et al., 1984; Schneider & Bell, 1985). Canopy cover and aboveground biomass of kwongan on the deep, acid sands of the Northern Sandplain were equivalent to prefire conditions after only 7 years at Jurien (Delfs et al., 1987) and 9 years at Eneabba (Hopkins & Hnatiuk, 1981). Biomass recovery of shrub vegetation on the calcareous sands of the Southern Sandplain near Albany reached preburn values after 9 years (Bell et al., 1984).

V. Autecological Patterns

Although resprouting provides a perceived advantage in habitats with recurrent fires (Mooney & Dunn, 1970), resprouting is a widely occurring trait in woody plants of all environments and has clearly evolved in response to more than just fire (Biswell, 1974; Gill, 1975; James, 1984; Zedler & Zammit, 1989). In addition to being advantageous as a postfire recovery trait, resprouting has also proved beneficial against other environmental stresses, such as drought (Hnatiuk & Hopkins, 1980), vertebrate browsing (Quinn, 1986), insect damage (Morrow, 1977), and low nutrient regime (Specht, 1979). However, the resprouter-versus-reseeder fire-response dichotomy provides an opportunity to compare and contrast autecological strategies between co-occurring, congeneric pairs of species that differ predominantly in the way they respond to fire. There are, however, limitations to such studies, and Lamont and his coworkers (Lamont et al., 1998) have provided some additional recommendations when choosing species pairs for st udy. These include: species pairs should not only co-occur but be interspersed; species pairs should not only be congeneric but sister species as well; and, ideally, the species pairs should differ morphologically only in their fire response. In the remainder of this section I compare autecological attributes of resprouters and reseeders in relation to life-history pattern. However, in most cases all the preconditions of Lamont et al. (1998) have not been strictly observed; therefore, caution is required in interpreting the results.


The germination of species from southwestern Western Australia in response to the environmental cues involving fire and the postfire environment has received considerable attention (see reviews by Bell et al., 1993; Bell, 1999). In addition to fire-response syndromes, species from Western Australia have been separated into seed-storage syndromes. Species either disperse seeds annually to the soil (soil-stored seeds) or retain their seeds in protective structures on the plant (bradysporous seeds) (Lamont et al., 1991b). Soil-stored seeds must be able to tolerate the passage of the fire, and there is a benefit if soil-borne seeds remain dormant until some postfire environmental cue leads to germination (Bell, 1999). Canopy-borne seeds are protected from the thermal effects of fires by woody fruits (Bradstock et al., 1994). Following fire, the fruits open to disperse seeds into a nutrient-, light-, and moisture-rich environment.

Soil-borne seed storage in Western Australian species is usually associated with thick seed testas (Bell & Williams, 1998). Thermal tolerance of seed from reseeding species may be expected to be greater than that of resprouting species. Acacia saligna, a resprouting species, is relatively intolerant of heat shock compared with other species of Acacia. Bossiaea ornata, also a resprouter, is less tolerant of thermal shock than is its congeneric seeder, Bossiaea aquifolium. However, when all tests on the 14 Western Australian legumes of these trials were considered, the wide variation in levels of lethal duration of heat shock between resprouters and reseeders resulted in insignificant differences.

In Western Australian soil-borne species without thick seed testas, a germination cue in the form of some water-soluble product from the postfire environment may break dormancy and induce germination. Smoke from the burning of native vegetation (Dixon et al., 1995; Roche et al., 1997; Smith et al., 1999) and postfire levels of soil nitrates (Bell et al., 1999; Plummer et al., 2001) have been implicated. However, among the soil-storage syndrome species, there appears to be no basic difference in the viability and germinability of seeds between resprouting species and reseeding species (Bell et al., 1995; Roche et al., 1997; Cochrane et al., 2002).

One could argue that, in order to survive a fluctuating climatic regime, it would be evolutionarily advantageous to develop mechanisms that would closely track the environmentally favorable times for seedling survival. Seeds capable of preventing germination after occasional summer rainfall events that merely wet the surface soils would seem to have an advantage over seeds that immediately imbibe water and germinate but later die when the surface soil moisture dries out. Most species of the southwestern Western Australian flora have low temperaturegermination optima (Bellairs & Bell, 1990a; Bell & Bellairs, 1992; Bell, 1994). Low temperature optima and a narrow range of germination response to temperature are especially common attributes in species with low seed weight (Bell, 1994). In germination trials with 43 Western Australian species, large forest canopy-resprouting species germinated at a wide range of trial temperatures, understory-resprouting species germinated at lower temperatures and within a narr ower range of temperature optima, and understory reseeding species were generally restricted to germinate only at or near the 15[degrees]C trial incubation temperature (Bell et al., 1995). The 1 15[degrees]C trial temperature is typical of the temperatures present during the winter wet season in these Mediterranean-type climates. Therefore, in the autecology associated with germination, only in the response to temperature is there a fire-syndrome difference, where reseeders appear to have a narrower germination optimum range than do resprouting species.


Although reseeders allocate more resources to the production of seeds and are, therefore, likely to have higher numbers of postfire seedlings (Keeley, 1977; Carpenter & Recher, 1979), the ability to establish and survive the first summer drought season can also be important (Richards & Lamont, 1996). A large proportion of the seed rain of species in southwestern Western Australia is collected and eaten by ants (Yates et al., 1995), but failure of species reestablishment following fire is often attributed to the failure of seedling establishment (Baird, 1984; Cowling & Lamont, 1987; Enright & Lamont, 1989; Yates et al., 1996). Seedlings of the resprouters are especially rare in the year following fire in the Banksia-dominated woodlands near Perth (Baird, 1984; Hopkins & Griffin, 1989; Hobbs & Atkins, 1990).

Seed-bank studies from Western Australia generally indicate that reseeders maintain higher numbers than do resprouters in both soil-stored-seed species (Vlahos & Bell, 1986; Meney et al., 1994) and canopy-stored-seed species (Cowling & Lamont, 1987). Seedling:parent ratios following fire in a number of members of the Epacridaceae and Restionaceae from the Northern Sandplain indicated that all species, regardless of their fire-response strategy, have the capacity to reconstitute parent densities from germinants in the first year after fire (Meney et al., 1994). However, high seedling mortality and no further recruitment after the initial postfire year indicated that, in some species, survival of postfire reseeders was less than replacement in the long term.

Although fire regimes in southwestern Western Australia seem to favor the resprouter strategy, reseeding species effectively reestablish populations following fire. Hakea obliqua and Beaufortia elegans, two reseeding species of the Northern Sandplain illustrate this (Bell et al., 1987). Because both species are bradysporous, estimates of prefire seed populations can be easily made, as can postfire seedling population estimates. In one area, where more than 15 years had passed since the last fire, estimates of H. obliqua seeds totaled 3,800 [ha.sup.-1], with the seeds of Beaufortia elegans numbering 29,600,000 [ha.sup.-1]. After an autumn fire and two months subsequent to the first rains of winter, counts of seedlings showed that about 16% of the H. obliqua seeds had succeeded in establishing seedlings, whereas only about 8% of B. elegans seeds had established seedlings. Therefore, H. obliqua appears to have opted to allocate its reproductive resource into few, large seeds, which have a greater potential to e stablish fast-growing seedlings following fire. Beaufortia elegans, on the other hand, relies on a massive, synchronous dispersal of large numbers of small seeds, thereby satiating the harvester ant population and relying on a postfire environment higher in nutrients, light, and moisture to supplement inherently slower, early growth rates.

Seed mass is usually directly related to seedling survival (Stock et al., 1990; Westoby, 1992; Kidson & Westoby, 2000). In southwestern Western Australian, both resprouters and reseeders have a wide range of seed weights (Bell et al., 1995; Grant et al., 1996; Bell & Williams, 1998). For example, among resprouters, Agonis flexuosa seeds weigh 0.04 mg and Corymbia calophylla seeds weigh more than 93 mg. Among reseeders, Stylidium calcaratum has a seed weight of only 0.02 mg, but Paraserianthes lophantha weighs more than 76 mg. Even within a single genus there is considerable variation. Seeds of Acacia saligna, a resprouter, weigh 18 mg, yet two reseeders, A. lasiocarpa and A. drummondii subsp. candolleana, weigh 5 and 35 mg, respectively. Pate et al. (1985) also found no basic difference in seed numbers, seed size, or seed mineral composition between representative resprouters and reseeders of the Northern Sandplain. Although the concentration of antiherbivore compounds in seeds of Western Australian species has not been measured, in studies of seed granivores of Banksia species, seeds of reseeders appear just as prone to insect predation as do seeds of resprouters (Scott, 1982). Also, there is no major dichotomy in seed weights or seed nutrition between resprouters and reseeders, but large seeds from Western Australia have a greater capacity to emerge from depth in the topsoil (Grant et al., 1996).

Although large seeds have an advantage in emergence from depth, there is a resource trade-off in the production of seeds. Species that produce large seeds tend to produce few seeds; those with small seeds produce many (Bell et al., 1987; Lamont & Groom, 1998). Large-seeded species also tend to produce larger seedlings than do co-occurring, congeneric species with small seeds in the first year following fire (Richards & Lamont, 1996). Studies with Hakea ruscifolia, a small-seeded, resprouting species, H. smilacifolia, a small-seeded, reseeding species, and H. polyanthema, a large-seeded, reseeding species indicated that survival in the first year following fire was related to seed size (and to the size of resulting seedlings), rather than mode of fire recovery. Postfire, first-year seedling survival data on six species of Banksia from the Northern Sandplain seemed to indicate that survival of needleleaved species was greater than survival of seedlings with broad leaves, regardless of the mode of fire response (Enright & Lamont, 1989). A subsequent, carefully controlled study using Banksia attenuata, a resprouter with broad leaves, B. hookeriana, a reseeder with broad leaves, and B. leptophylla, a reseeder with needle-like leaves, also measured first-year seedling survival (Enright & Lamont, 1992). First-year survival in those three Banksia species was related more to leaf morphology than to fire-response strategy. In the California chaparral genus Ceanothus, seedlings of reseeding species survive in greater percentages than do cooccurring, congeneric resprouter seedlings (Frazer & Davis, 1988; Thomas & Davis, 1989). In southwestern Western Australia, however, the evidence gathered so far in dicates that differences in establishment rates between seedlings of resprouters and seedlings of reseeding species are generally more a consideration of ecophysiological and ecomorphological attributes than of those strictly inherent in the resprouter/reseeder dichotomy in fire-response strategy (Groom & Lamont, 1995).


Western Australian reseeders have generally been shown to have higher initial growth rates than resprouters (Pate et al., 1990). In comparisons between congeneric pairs of species in the genera Dryandra, Banksia, Conospermum, Stirlingia, Bossiaea, Hovea, and Acacia, seedlings of the resprouters after 2-4 years had only about one-third the dry weight of comparably aged reseeders. Patterns of starch deposition also varied between resprouters and reseeders. Although storage of starch in seedling shoots of the two fire-response strategy types was not different, root starch storage of the resprouters was much greater. Measures of both shoot and root concentrations of the minerals N, P, Ca, K, and Mg on the seedlings of the 40 resprouters and 25 reseeders, however, showed no significant differences between the two fire-syndrome types.

A second, more detailed study of seedlings of resprouters and reseeders concentrating on congeneric pairs within Proteaceae also found significantly smaller shoot:root ratios in resprouter seedlings compared with ratios measured in comparably aged seedlings of reseeders (Bowen, 1991; Bowen & Pate, 1993). Again, the seedlings of resprouters had larger concentrations of starch in their roots and significantly greater proportions of their root tissue as parenchyma available for, but not necessarily utilized for, starch storage. Within resprouters, the starch storage and increased area of potential storage tissue was observed in both the cortex and the ray tissue or in the cortex alone. Also in this study, there were no consistent differences between the two fire-response strategies in terms of concentrations of C, N, P, Ca, Mg, and K in either shoots or roots.

Greater rates of early growth, however, are not a universal attribute of reseeding species from southwestern Western Australia. There was little difference in the early relative growth rates between congeneric legume pairs of resprouter and reseeder species from the Western Australian jarrah forest (Hansen et al., 1991). Also, in seedlings of congeneric pairs in the Epacridaceae, there were no basic distinctions between resprouter and reseeder representatives in terms of seedling growth rate (Bell, 1995; Bell & Pate, 1996). However, the epacrid resprouters achieved only one-third the shoot:root ratios during comparable periods of growth and accumulated much more root starch reserves than did the reseeders. Although the epacrid reseeders did not grow faster than the epicrid resprouter seedlings, they commenced flowering earlier.


The physiognomy of mature resprouting shrubs in southwestern Western Australia is generally different from that displayed by reseeding species (Baird, 1977; Delfs et al., 1987). Multiple shoots regenerating from the lignotuberous root stock give resprouters a characteristic "urn" shape, with a wide basal diameter and aboveground biomass concentrated mainly at the base of the plant. Resprouters also tend to have a massive, deeply penetrating root system (Dodd et al., 1984; Low & Lamont, 1990). In contrast, reseeding species typically have a single, persistent main stem with divaricating upper branches. Eventually the aboveground biomass is distributed mostly in the upper reaches of the plant, giving the crown silhouette an "umbrella" shape. Reseeding species most commonly have a shallow, fibrous root system. Because the reseeders tend to establish in spaces between the regenerating crowns and in time even overtop the resprouters, both are able to coexist successfully for many years after a fire. Indeed, a mix of resprouters and reseeders, with essentially complementary shoot canopies and rooting morphologies, is likely to maximize utilization of existing ground cover, rhizosphere, and resources of light, water and nutrients. In the early years following fire, reseeding species show a positive relationship between height and age-since-burn; however, in older reseeders and all postfire resprouters, height is not a good predictor of age (Delfs et al., 1987). The established relationships between reseeder shrub heights and age-since-last fire have been used to construct fire-age maps for land-use management decisions in the Northern Sandplain (Bell, 1985).

Shoot:root ratios of sexually mature individuals of the Northern Sandplain reseeder, Banksia hookeriana, were determined to be 3.12, compared with 0.45 and 0.66 for the two cooccurring resprouters, B. attenuata and B. menziesii (Lamont et al., 1985b). The reseeder also tended to have a larger proportion (32%) of the shoot material contributed by reproductive structures compared with the two resprouters (less than 20%) (Low & Lamont, 1990). A comparable study of co-occurring eastern Australian Banksia species also showed that reseeders allocated a greater proportion of aboveground biomass to reproductive features than did resprouters (Groves et al., 1986).

A study of 82 species of the Restionaceae from southwestern Western Australia also showed vegetative differences between resprouting and reseeding species (Pate et al., 1991). The resprouting members of this monocotyledonous group had much lower culm:rhizome ratios. Rhizome diameters of the resprouters were larger, and the mean position of perennating buds of the resprouters was deeper. Starch was present in rhizomes of most of the resprouting species, whereas only three of the 45 reseeding species harbored rhizome starch. Sugar content in the rhizomes of the resprouters was also significantly higher than was that of the reseeders.

Resprouting species generally have less efficient nutrient retention than do reseeding species (Lamont et al., 1985b; Cowling & Lamont, 1986). In the Northern Sandplain kwongan near Eneabba, four co-occurring species of Banksia can be found. Banksia attenuata, B. menziesii, and B. candolleana, all resprouting species, tend to retain their leaves for 2 years, with some leaves retained in a third annual whorl of leaves. The fourth species, B. hookeriana, a reseeder, retains its leaves for at least 4 years, with some leaves in the fifth-year whorl. This pattern of leaf retention indicates that B. hookeriana is much more conservative with its internal nutrient supply than are its co-occurring resprouting relatives. The resprouting species can afford to drop leaves, because they can expect to reattain required nutrients through the normal external decomposition cycle, since individuals will survive many years and through periods of several fires.


Western Australian plant communities rapidly return to reproductive potential following fire. Although it may be expected that the time after fire to return to reproductive maturity in resprouters would be less than that of reseeders, information on age to first postfire flowering from sites near Jurien Bay showed no mean difference in juvenile period for most species (van der Moezel et al., 1987b). Common reseeding species from this Northern Sandplain area, such as Dryandra sessilis, D. kippistiana, Petrophile media, Beaufortia elegans, and Leucopogon striatus, flowered when they were only two years old. In a few instances, such as in Hakea obliqua and Dryandra carlinioides, however, the primary juvenile period exceeded four years. In the jarrah forest communities of the Darling Range, 90% of understory species flowered within two years of fire and 100% within three years (Burrows et al., 1995). Although both primary and secondary juvenile periods are short in southwestern Western Australian plant communiti es, sufficient seed set to reestablished populations of reseeders is usually insufficient until about twice to three times the primary juvenile period (Burrows et al., 1995; Gill & McCarthy, 1998). Resprouting species of Banksia usually set fruit within 1-3 years of a fire (Lamont, 1988), but seedlings in some species require up to 20 years to reach maturity (Abbott 1985; Lamont & van Leeuwen, 1988).

Wiens et al. (1987) have shown that there are strong correlations between growth and life-forms (i.e., annual vs. perennial and herbaceous vs. woody) and reproductive features, such as seed:ovule ratios. Carpenter and Recher (1979) were the first to attempt to link fire-response stratgies with reproductive features, such as fecundity and breeding systems. They hypothesized that resprouters would maximize outbreeding and, therefore, the quality of the annual seed crop. In contrast, reseeders would maximize fecundity or seed numbers, with selfing contributing to the fertilization of ovules. In the resprouters fitness is less dependent on maximizing seed output, because individuals survive fire. Therefore, in the resprouters seeds can act more as agents of dispersal and genetic novelty (Fulton & Carpenter, 1979). However, the advantages of outcrossing in uncertain habitats lends support to the belief that reseeders would have even more evolutionary pressure placed upon them than would the more conservative resp routers for this trait. Attributes associated with maximizing outcrossing to ensure high annual seed production would include abundant pollinator rewards, many flowers per unit of crown volume, and a high seed:ovule ratio (Carpenter & Recher, 1979).

Measures of production of seeds by bradysporous shrubs in Western Australian kwongan vegetation at Kulin and Eneabba indicated that the reseeder in each of six congeneric pairs had a considerably larger canopy seed reserve than did the resprouter (Bellairs & Bell, 1990b; Bellairs, 1992). Other studies have also documented the tendency for bradysporous resprouting species to have fewer seeds per plant than do congeneric reseeding species (Lamont, 1985b; Enright & Lamont, 1989).

Reproductive success can be assessed by seed:flower or seed:ovule ratios. Four Banksia species grow in the shallow ridge-and-swale vegetation of the Yule Brook Botany Reserve near Perth (Lewis & Bell, 1981; Stevens, 1985). The two upland resprouters, B. menziesii and B. attenuata, have very low seed:flower ratios, averaging 0.81 and 0.5 1%, respectively. Of the two Banksia species growing in the occasionally flooded swales, B. telmatiaea, a reseeder, had a much higher seed:flower ratio, 6.7%, than did the upland resprouters, but B. littoralis, a resprouter sharing the same lowland habitat, also showed a comparably high seed:flower ratio, 6.9%. The B. littoralis result could not be exceptional, for the species also showed a reasonably high percentage seed set, 6.5%, in studies by Wheland and Burbidge (1980), who also recorded values of less than 1% for seed set in B. menziesii and B. attenuata.

Determining the seed:ovule ratio in 22 species from three related monocotyledonous families showed that the resprouting species had less reproductive success (35%) than did the reseeding species (67%) (Meney et al., 1997). A similar study using congeneric pairs of legume species of the jarrah forest also showed that resprouters have significantly smaller seed:ovule ratios than do reseeders (Hansen, 1990; Hansen et al., 1992).

A study of two pairs of jarrah forest understory species also provided some valuable information on reproductive features (Lamont et al., 1998). Dryandra sessilis, a reseeder, produced far more seeds annually than did the cohabitant, congeneric resprouter, Dryandra lindleyana subsp. lindleyana. The prolific seed set in D. sessilis was due to prolific flower production and an effective outcrossing breeding system, which ensured a high fruit: flower ratio. In the second jarrah forest understory species pair, the reseeder, Hakea erinacea, was also a prolific seed producer, which outproduced the co-occurring resprouter, Hakea cristata. However, prolific seed production in H. erinacea was the result of its smaller fruits, and the high fruit:flower ratio was associated with effective selfing. Although these attributes of seed production and fruit:flower ratio correlated with fire-response strategy expectations, a large number of other flowering phenology, pollinator attractants, and reproductive attributes did not . Such contradictions should be carefully taken into account, because other physiological attributes may be the cause of the association between levels of fertility and life-form (Lamont, 1985c). In South Africa, a detailed study of three species of Leucospermum, L. cuneiforme, a resprouter, and two reseeders, L. cordifolium and L. erubescens, on a wide range of reproductive attributes provided almost no support for the hypothesis that resprouters minimize their reproductive effort in association with self-incompatibility (Lamont, 1985c).

Data acquired from two eastern Australian species of Banksia lend support to the hypothesis that reseeders show greater levels of selfing than do resprouters. Banksia spinulosa is a lignotuberous, resprouting shrub with low seed set. Banksia ericifolia is a reseeding species of the same habitat, which generally has a much higher level of seed set. Both species tend to be highly outcrossed, but B. ericifolia shows self-compatibility. The self-incompatibility breeding system of B. spinulosa ensures that the seeds will be of "superior quality." Being capable of surviving fires, this species can afford to maximize the quality of seed production. The requirement of producing some seed to ensure survival in the habitat for B. ericifolia has led to the acceptance of some selfing.

Reseeding species are less likely to be wind pollinated than are resprouters. The kwongan environment, especially in the Northern Sandplain of Western Australia, is extraordinarily windy (Bell et al., 1986) and is similar to such windy habitats as high-latitude conifer and deciduous forests, the prairies and steppes of the world, and oceanic islands (Whitehead, 1969). However, unlike the high-latitude plant communities, the proportion of Western Australian species adapted to wind pollination (anemophily) is very low. Anemophily is regarded as an ancient mechanism for pollination, especially among conifers (Sporne, 1965). In Western Australia, the conifers are represented by only nine species in two genera, Actinostrobus and Callitris. Grasses, sedges, and rushes have evolved anemophily in modern times (Stebbins, 1970), but these groups also have only limited numbers of representatives in Western Australian plant communities. The families Proteaceac, Mimosaceae, and Myrtaceae generally growing herbs Fulton MD dominate the kwongan. Th ese are families not generally noted for adaptations to wind pollination. Anemophily has been suggested for a few species of Eucalyptus (Pryor, 1976), but most eucalypts produce copious nectar, have conspicuous flowers, and are most often considered to be animal pollinated. Of the 413 vascular plant species of the Northern Sandplain region of the Beekeeper's Reserve surveyed by Wills (1989), anemophily represented only 8% of the flora. This compares with 13% for the entire Western Australian Southwest Botanical Province (Keighery, 1982) and 21% for the Eremacan Botanical Province (Keighery, 1982). The extreme richness of the kwongan is also a factor reducing the effectiveness of anemophily, which flourishes best when neighboring plants are conspecific (van der Moezel et al., I 987b). Also as Regal (1982) predicts, areas with uncertain environmental conditions will be dominated by breeding adaptations (e.g., animal pollination), which promotes ourcrossing.

Anemophily is often associated with dioecy in many plant groups (Sporne, 1965). Dioecious species are also very rare in southwestern Western Australia (McComb, 1966). Even in the genera with mostly dioecious representatives in Western Australia, such as Allocasuarina, only one of the shrubby kwongan members is monoecious (A. thuyoides). It seems that only species that resprout can carry the anemophilous mode of pollination. The requirement of the production of large amounts of pollen to overcome the disadvantages of a pollen vector, which is not guided to the style, is one that only long-lived, resprouting species can provide. Also, there are advantages of animal pollination in uncertain habitats for cross-fertilization and the genetic benefits of outbreeding.

In conclusion, resprouters are not conclusively blessed with one set of characteristics and reseeders with the complete opposite (Table III). Resprouters tend to have a long primary juvenile period, but exceptions are many. Resprouters tend to have more flowers and flowers with greater rewards for pollinators. Numerous, outcrossed, energy-charged, viable, and germinable seeds are the expectation for reseeders, but exceptions are numerable. Postfire populations of reseeders can be higher than their parent numbers, but seedling survival is critical to whether postfire communities are markedly altered or much the same as before. The postfire seedlings of the reseeders exploit the aboveground environment, growing more rapidly upward, conserving nutrients in leaf tissues, and expending more energy in the production of reproductive tissue. The postfire seedlings of resprouter species exploit the belowground environment, storing energy in the root system and growing a deeply penetrating root system. The survival of species in a fire-prone environment can involve a wide range of combinations of attributes. It appears that lack of an ability to resprout may be offset by a number of other structural and functional features.

VI. Conservation and Management

Fire-regime management can have drastic effects on species diversity. Fires that are too frequent or too infrequent can both affect the flora. Reseeders can become locally extinct if an area is burned twice within a few years (Gill, 1977). Studies in the Western Australian jarrah forest have determined that a fire-free period equal to twice the primary juvenile period is needed to allow adequate seed production (Burrows et al., 1995); Similar methods of determining appropriate minimum fire intervals have also been suggested for eastern Australia vegetation (Gill & McCarthy, 1998) and Cape Region fynbos (Kruger & Lamb, 1978). Frequent burning of fynbos eliminates most of the reseeding species (Van Wilgen, 1982). In Western Australia, it is clear that short fire intervals can have drastic impacts on reseeders, but it is unclear whether an extremely long fire-free period can also result in the local extinction of species. Estimates for the upper limit of combined plant and seed longevity in fire-prone California communities exceed 200 years (Keeley, 1986). The continued co-occurrence of both fire-response strategies in Western Australian plant communities is probably dependent on a fire regime with variable recurrence intervals. Therefore, fire-management regimes should also be planned to include a variable recurrence interval and a range of fire intensities. Conceptual models of fire and competition favor variability in fire interval to maintain a diversity of both fire-response syndrome representatives in eastern Australian heathlands (Keith & Bradstock, 1994; Morrison & Gary, 1994).

The season of the burn can also markedly affect survival of seedlings. Seedling regeneration in a banksia woodland near Perth was successful only after an autumn burn (Hobbs & Atkins, 1990). The best season for Banksia burdetti seed release, germination, and establishment after fire was late summer/autumn (Lamont & Barker, 1988). In Banksia ericifolia, the likelihood of postfire extinction is up to three times higher after winter-spring fires than summer-autumn fires (Bradstock & Bedward, 1992). Postfire recruitment of South African Proteaceae is also most successful following autumn bums, whereas winter and spring burns lead to very poor seedling establishment (Bond et al., 1984; Wright et al., 1990). Poor establishment following winter and spring burns is due partly to postfire seed (Cowling & Lamont, 1987) and/or seedling predation (Abbott, 1984) and partly to competition with the rapidly redeveloping resprouters (Lamont, 1 985a). The challenge of proper fire management is to establish a fire regime that a llows the co-occurrence of both regeneration strategies.

The Beekeeper's Reserve of the Northern Sandplain is a region of kwongan reserved for winter honeybee pastures (Wills, 1989). Among apiarists, it is commonly believed that extended fire-free periods are required for kwongan to achieve maximum nectar and pollen production (van der Moezel et al., 1987a). Farmers, however, fear that wildfires starting in kwongan will spread to their adjacent crops and demand frequent fuel-reduction bums. What is apparent is that both resprouters (e.g., Acacia stenoptera and Hakea lissocarpha) and reseeders (e.g., Dryazdra sessilis, Leucopogon conostephioides, and L. striatus) provide abundant nectar (Smith, 1969) and pollen (van der Moezel et al., 1987a). As with fuel-reduction burns in jarrah forest, a variable regime of fire intervals will maintain both types of fire response strategies in the vegetation of the Beekeeper's Reserve in amix of ages and will provide fire protection for adjacent farm properties. A mix of old and more recently burned habitat also appears to be impo rtant in the management of the vegetation of the Fitzgerald River National Park of the Southern Sandplain for rare birds (e.g., ground parrot, western bristle-bird, and mallee fowl)(Hassell, 2001).

Establishing a proper fire-management regime for rare or restricted-range plant species also requires more than just a basic knowledge of their mode of recovery following fire. Banksia cuneata, a reseeder, is found in only seven populations, with fewer than 350 individuals in total (Lamont ct al., 1991 a). A stochastic model incorporating aspects of plant longevity, seed production, inbreeding depression, seed viability, seedling recruitment, and seedling survival indicates that a moderate frequency of prescribed burning (intervals of 15-25 years) would increase the mean population size (Burgman & Lamont, 1992). However, the likelihood of a rainfall decrease of about 4% per decade due to global warming (Pittock, 1988) means that the risk of future extinction, even in the absence of prescribed fires, is high. The only way to ensure a reasonable chance of continued survival of B. cuneata populations appears to involve potential human intervention by watering seedlings through summer whenever a severe drought fo llows a fire.

Proper restoration of vegetation disturbed by mineral extraction also involves a thorough knowledge of the fire-response strategies of the species involved. A major challenge in the restoration of southwestern Western Australian mine sites is the lack of resprouters in the seed bank (Brooks & Bell, 1984; Bell, 1988; Bell et al., 1990). In the restoration of jarrah forest vegetation after bauxite mining, topsoil return initially produces a floristic composition very different from the original, and the supplementary seeding of resprouter species is important in maintaining species diversity (Bartle et al., 1978; Ward et al., 1993; Smith et al., 2000). A wide range of germination stimuli is used to germinate recalcitrant species, and field plantings of cuttings and tissue culture plantlets are also used to increase the species diversity of jarrah forest restoration areas (Hopkins et al., 2000; Koch & Ward, 2000). Subsequent prescription burning in rehabilitated mine-site vegetation can also affect the populatio ns of resprouters and reseeders (Smith et al., 2000).

Topsoil retention and respreading are also employed in the restoration of banksia woodland and kwongan vegetation in the Northern Sandplain following mineral sand extraction (Rokich, 1999). Adding a bradysporous seed-rich mulch to sand-mining rehabilitation areas returns some resprouters, but species richness and the density of resprouters are still well below comparative natural vegetation areas (Bell et al., 1990; Bellairs & Bell, 1993). Outplanting nursery-grown stock is also used to increase the density of resprouter species in sand-mine restoration (Bell et al., 1990).

The study of ecological syndromes and their significance to survival in particular environment has a long history (Griesebach, 1872; Raunkiaer, 1934). Identifying sets of contrasting plant attributes, such as fire-response syndromes, pollination guild, life-history strategy, seed-storage types, and functional groups based on seed-dispersal mechanisms, leaf types, root function, or floral structure, will benefit from additional, detailed studies of pairs or groups of evolutionarily related species. Such studies assist in the understanding of common adaptive features to environmental conditions. However, as this review of attributes related to fire has shown, "There is more than one way to skin a cat."

VII. Acknowledgments

The research reported here was supported by Department of Botany Research Funds of the University of Western Australia. Dr. William A. Loneragan and Dr. John M. Koch were instrumental in improving early drafts of the manuscript. Andreas Neuhaus kindly translated the abstract. My continued status in the Department of Botany as an honorary research fellow is appreciated.

VIII. Literature Cited

Abbott, I. 1984. Emergence and early survival of seedlings of six tree species in Mediterranean forest of Western Australia. Forest Ecol. & Managem. 9: 51-66.

-----. 1985. Reproductive ecology of Banksia grandis (Proteaceae). New Phytol. 99: 129-148.

Adamson, R. S. 1935. The plant communities of Table Mountain, III: A six years' study of regeneration after burning. J. Ecol. 23: 52-55.

Baird, A. M. 1977. Regeneration after fire in King's Park, Perth, Western Australia. J. Roy. Soc. W. Australia 60: 1-22.

-----. 1984. Observations on regeneration after fire in the Yule Brook Reserve near Perth, Western Australia. J. Roy. Soc. W. Australia 67: 1-13.

Bartle, J. R., J. McCormick & S. R. Shea. 1978. Direct seeding of native species: A technique for re-vegetation of disturbed areas in the jarrah (Eucalyptus marginata Sm.) forest. Pp. 99-104 in J. E. D. Fox (ed.), Rehabilitation of mined lands in Western Australia. Western Australia Institute of Technology, Bentley, Australia.

Beard, J. 5. 1990. Plant life of Western Australia. Kangaroo Press, Kenthurst, Australia.

Bell, D. T. 1985. Aspects of response to fire in the Northern Sandplain heathlands. Pp 33-40 in J. Ford (ed.), Fire ecology and management in Western Australian ecosystems. Western Australia Institute of Technology, Environmental Studies Group Report No. 14. Bentley, Australia.

-----. 1988. Seed-related autecology in restoration of minesites in Western Australia. Pp.5-33 in E. B. Allen (ed.), The reconstruction of disturbed arid lands: An ecological approach. AAAS Selected Symposium 109. Westview Press, Boulder, CO.

-----. 1994. Interaction of fire, temperature and light in the germination response of 16 species from the Eucalyptus marginata forest of south-western Western Australia. Austral. J. Bot. 42: 501-509.

-----. 1999. The process of germination in Australian species. Austral J. Bot. 47: 475-517.

----- & S. M. Bellairs. 1992. Effects of temperature on the germination of selected Australian native species used in rehabilitation of bauxite mining disturbance in Western Australia. Seed Sci. & Technol. 20: 47-55.

----- & J. M. Koch. 1980. Post-fire succession in the northern jarrah forest of Western Australia. Austral. J. Ecol. 5: 9-14.

----- & W. A. Loneragan. 1985. The relationship of fire and soil type to floristic patterns within heathland vegetation near Badgingarra, Western Australia. J. Roy. Soc. W. Australia 67: 98-109.

----- & D. S. Williams. 1998. Tolerance of thermal shock in seeds from Western Australia. Austral. J. Bot. 46: 221-233.

-----, A.J.M. Hopkins & J. S. Pate. 1984. Fire in the kwongan. Pp. 178-204 in J. S. Pate & J. S. Beard (eds.), Kwongan: Plant life of the sandplain. Univ. of Western Australia Press, Nedlands.

-----, D. Carter & R. Hetherington. 1986. Experimental assessment of wind erosion after soil stabilization treatments at Eneabba, Western Australia. Environ. Geochem. Health 8: 99-104.

-----, P. G. v
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Security guard, gunman dead after federal building shooting

04 Dic 2015 
NEW YORK (AP) An armed veteran slipped through a side door of a federal building on Friday and shot a security guard in the head, killing him, before fatally shooting himself, police said.

Detectives were investigating what prompted the shooting of FJC Security Services guard Idrissa Camara, who was supposed to have gotten off work at 4 p.m. but agreed to stay on for an extra shift.

The shooter, Kevin Downing, entered through a side entrance of the Manhattan building, which houses an immigration court, a passport processing center and a regional office for the Department of Labor, police said.

Downing was a former federal employee at the Bureau of Labor Statistics, police Deputy Commissioner for Intelligence and Counterterrorism John Miller said. But it was unclear if Downing, of Fort Lee, New Jersey, had worked at the building where the shooting occurred, about a mile and a half from the World Trade Center.

Downing had collected Veterans Affairs benefits, but police were still determining which branch of the armed service he served.

He shot Camara, 53, at close range, then walked through a screening area and headed toward an elevator, where he encountered another employee, and then he shot himself in the head, said James O'Neill, a chief with the New York Police Department. He was pronounced dead at the scene.

Federal agents were at Downing's suburban home, awaiting a court order to begin searching it for anything that could provide investigators with insight about what prompted the shooting, Miller said.

"We don't know what his target was," O'Neill said. It appears the gunman acted alone, and O'Neill said there was no indication the shooting was terrorism.

Miller said Downing had left his government job "some time ago." A spokesman for the U.S. Department of Labor, which controls the Bureau of Labor Statistics, did not immediately respond to a message seeking comment. The FBI was assisting in the investigation because Camara was working as a contractor for a federal agency, police said.

Camara, a senior guard, was armed but never had a chance to defend himself, according to the security company.

"Camara ... was an extraordinary Senior Guard who was well trained, cared deeply about his job and knew that building better than anyone else," said Michael McKeon, a spokesman for the security officer jobs, corporate social responsibility jobs, corporate social responsibility policy, corporate social responsibility examples, examples of corporate social responsibility, private security contractors, social responsibility in business, definition of corporate social responsibility, csr policy, csr companies, private security companies, corporate social responsibility india, security officers, business ethics and social responsibility, csr jobs, security jobs in London, it security policy, definition of csr, concept of corporate social responsibility, social responsibility of business, social corporate responsibility, corporate social responsibility ppt, corporate responsibility, health and safety jobs, security officers jobs, security and safety management, corporate social responsibility uk, corporate it security, corporate responsibility jobs, corporate security jobs security company. "Our thoughts and prayers are with his wife and family. We intend security officer jobs, corporate social responsibility jobs, corporate social responsibility policy, corporate social responsibility examples, examples of corporate social responsibility, private security contractors, social responsibility in business, definition of corporate social responsibility, csr policy, csr companies, private security companies, corporate social responsibility india, security officers, business ethics and social responsibility, csr jobs, security jobs in London, it security policy, definition of csr, concept of corporate social responsibility, social responsibility of business, social corporate responsibility, corporate social responsibility ppt, corporate responsibility, health and safety jobs, security officers jobs, security and safety management, corporate social responsibility uk, corporate it security, corporate responsibility jobs, corporate security jobs to do everything we can to stand with them during this very difficult time."

Hector Figueroa, the president of Camara's union, 32 BJ SEIU, said he was horrified by the news.

"Security officers around the city and country serve on the front line each and every day to keep us safe and secure," Figueroa said. "We are heartbroken that one of our own has fallen."

Employees at the building said they were told to get down on the ground when the shots rang out. A short time later, the building was placed on lockdown and then was evacuated.


Associated Press writers Michael Balsamo, Jennifer Peltz and David B. Caruso contributed to this report.

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