Black Cypress-pine Callitris endlicheri 
fire-sensitive vegetation recovery 
following high intensity bushfire

Black Saturday Victoria 2009 – Natural values fire recovery program
Heidi Zimmer, David Cheal, Ian Lunt, Glen Johnson

Black Cypress-pine Callitris endlicheri fire-sensitive vegetation recovery following high intensity bushfire
David Cheal
Arthur Rylah Institute for Environmental Research
Department of Sustainability and Environment
PO Box 137, Heidelberg VIC 3084.
Heidi Zimmer
Arthur Rylah Institute for Environmental Research
Current address: School of Biological Sciences,
Faculty of Science, Monash University, 
Clayton, VIC 3800.
Ian Lunt
Institute for Land, Water and Society
Charles Sturt University
PO Box 789 Albury, NSW 2640. 
Glen Johnson
Department of Sustainability and Environment
1 McKoy Street, Wodonga VIC 3690.
This project is No. 10 of the program ‘Rebuilding Together’ funded by the Victorian and Commonwealth governments’ Statewide Bushfire Recovery Plan, launched October 2009.
Published by the Victorian Government Department of Sustainability and Environment Melbourne, June 2012.
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Citation: Zimmer, H., Cheal, D., Johnson, G. and Lunt, I. (2012). Black Cypress-pine Callitris endlicheri fire-sensitive vegetation recovery following high intensity bushfire. Black Saturday Victoria 2009 – Natural values fire recovery program. Department of Sustainability and Environment, Heidelberg, Victoria.
Front Cover photograph: Chiltern–Mt. Pilot National Park, 2010; burnt in 2003. 
C. endlicheri showing strong seedling recruitment (David Cheal).

Contents
List of tables and figures	iii
Acknowledgements	v
Summary	vi
Introduction	1
Section 1 – Flagstaff Range and new data	3
1.1	Methods	3
1.1.1	Study site: Flagstaff Ranges	3
1.1.2	Study site: Mt. Pilot	4
1.1.3	Study design	4
1.2	Results	6
1.2.1	Demographics	6
1.2.2 	Seedling density and growth	7
1.2.3	Comparison of Flagstaff Ranges and Chiltern-Mt. Pilot	8
1.2.4 	Fecundity	8
1.3 	Discussion	9
1.3.1 	Impacts of browsing	10
1.3.2	Impact of environmental conditions	11
Section 2 – Mt. Pilot and new analyses of existing data: The tortoise and the hare? 
Post-fire regeneration in mixed Eucalyptus-Callitris forest	12
Introduction	12
2.1 	Methods	12
2.1.1 	Study area	12
2.1.2	Data analysis	13
2.2 	Results	13
2.2.1	Seedling density and mortality	13
2.2.2 	Seedling growth rates	13
2.2.3	Fencing effects	14
2.2.4 	Factors associated with seedling height	14
2.2.5 	Seed cone production	15
2.3 	Discussion	15
2.3.1 	Seedling growth rates	15
2.3.2 	Browsing damage	16
2.3.3	Seedling mortality	16
2.3.4 	Seed cone production	17
2.4 Conclusion	17
Section 3 – Summary of Management Implications	18
3.1	How does the response of C. endlicheri to fire vary with fire frequency?	18
3.2 	Is the persistence and recovery of C. endlicheri at a site affected by competition with associated eucalypts? 
Are mixed stands (Eucalyptus and Callitris) more prone to Callitris extinction or decrease after fires than are 
pure stands of Callitris?	19
3.3	Are the structure and fire responses of the Flagstaff Range C. endlicheri population (a small mixed stand) 
comparable with the population structure and post-fire responses of the much larger stands north of Beechworth, 
around Mt. Pilot? How far can we extrapolate results from study of the Mt. Pilot population?	19
3.4	Does exclusion fencing (or other browsing reduction) increase the likelihood of Callitris seedling survival and growth?	19
3.5	How many years before C. endlicheri produce seed? Is tree size a better indicator of fecundity than tree age?	19
3.6	Concluding remarks	20
References 	21

List of tables and figures
Table 1. 	Indicators of cone health/ viability, and number of individuals.	9
Table 2. 	Model statistics for linear mixed models describing the factors associated with Callitris seedling heights in 2010.	15
Table 3. 	Model statistics for linear mixed models describing the factors associated with Eucalyptus seedling heights in 2010. 	15

Figure 1. 	Flagstaff Range, E. polyanthemos resprouting from lignotubers at or below ground level, all C. endlicheri dead; 
eight months post-fire.	3
Figure 2. 	Flagstaff Range, corner of Exclosure 1 showing C. endlicheri, cones and intact small branches.	4
Figure 3. 	Flagstaff Ranges Exclosure 2, 100% C. endlicheri mortality as well as bare soil and runoff issues at the site; 
eight months post-fire.	4
Figure 4. 	Chiltern-Mt. Pilot National Park, 2010; burnt in 2003. C. endlicheri showing strong seedling recruitment.	4
Figure 5. 	Marking stake for permanent monitoring plot at Flagstaff Range.	5
Figure 6. 	Callitris endlicheri seedling affected by browsing.	5
Figure 7. 	Tagged C. endlicheri seedling.	5
Figure 8. 	Size structure (dbh) of burnt/ pre-fire C. endlicheri at Flagstaff Range.	6
Figure 9. 	Total basal area of C. endlicheri and Eucalyptus spp. at Flagstaff Range plots.	6
Figure 10. 	Exposed hill slope, organic litter and finer-grained surface soil removed by heavy storms soon 
after the 2009 fire, Flagstaff Range.	7
Figure 11. 	Mean density of seedlings inside and outside exclosures, Flagstaff Range.	7
Figure 12. 	Mean height of seedlings inside and outside exclosures, Flagstaff Range. 	7
Figure 13. 	Sub-plot ground cover according to number of seedlings, Flagstaff Range.	7
Figure 14. 	Mean density of seedlings inside and outside fences at Chiltern-Mt. Pilot, according to year.	8
Figure 15. 	Height of seedlings inside and outside fences at Chiltern-Mt. Pilot, according to year.	8
Figure 16. 	Double rings (left) and poorly differentiated rings (right).	8
Figure 17. 	Number of cones in each cone size class at Chiltern-Mt. Pilot, 2010.	9
Figure 18. 	Old fire scar on a veteran C. endlicheri, indicating survival from a previous fire, Flagstaff Range. 	9
Figure 19. 	Old fire scar on a veteran C. endlicheri, indicating survival from a previous fire, Flagstaff Range.	9
Figure 20. 	Seedling regenerants, C. endlicheri, Flagstaff Range.	10
Figure 21. 	Callitris seedlings clustered in litter, Flagstaff Range.	11
Figure 22. 	Predicted density of live (a) Callitris and (b) Eucalyptus seedlings in fenced and unfenced plots 
after the 2003 fire at Mt. Pilot. 	14
Figure 23. 	Predicted mean height of (a) Callitris and (b) Eucalyptus seedlings in fenced and unfenced plots.	14
Figure 24. 	The proportion of Callitris seedlings in different height classes that possessed seed cones in 2010.	15

Acknowledgements
This project is No. 10 of the program ‘Rebuilding Together’ funded by the Victorian and Commonwealth governments’ Statewide Bushfire Recovery Plan, launched October 2009.
For Section 2 we extend our thanks to Brian Pritchard of Parks Victoria for field support; students in the subject ‘Vegetation and Disturbance Ecology’ at Charles Sturt University, who collected the data on which this report is based; and Graham Hepworth for his excellent statistical support.
Section 2 of this report is concurrently published in the Australian Journal of Botany (2011) volume 59, pages 575–581.

Summary
This study investigated the response of Black Cypress-pine Callitris endlicheri (Parl.) F.M. Bailey to fire at sites in northern Victoria – Flagstaff Range, near Beechworth and the Warby Ranges (2009 fires), and Mt Pilot (2003). Callitris endlicheri is fire-sensitive and is usually killed by fire. The study aimed to inform land managers on how to manage to maintain this, and other, Callitris species, which are a distinctive component of the Victorian flora.
Grazing exclosures were established in areas burnt in 2009 and additional data was obtained from sites established by Charles Sturt University after a 2003 bushfire. These sites have been revisited and monitoring data collected (almost) annually from 2004–2010. Data was collected on basic demographics including seedling density and growth, size versus age and fecundity.
Comparisons of the responses to fire in the small, mixed stand at Flagstaff Range and the larger, more pure stand of Black Cypress-pine at Mt. Pilot showed similar ecological response.
At Mt. Pilot, there was no significant difference in seedling density between fenced and unfenced areas but seedlings in exclosures were significantly taller.
Consistent with expectations, Eucalyptus seedlings grew faster than Callitris seedlings in most situations. Callitris seedlings grew faster and produced seed cones sooner in plots with fewer Eucalyptus seedlings compared to plots with dense Eucalyptus seedlings. 83% of cones were on seedlings taller than 1.5 m and 23% of seedlings >2 m possessed seed cones.
The local growth rates of Callitris seedlings were not associated with long-term site suitability for Callitris, as many plots with diminutive Callitris seedlings and dense Eucalyptus seedlings were dominated by Callitris trees before the 2003 fire.
Contrary to expectations, few Callitris seedlings died during the six-year period, so competition during the regeneration phase did not regulate co-existence.
Strong drought tolerance and the ability to persist in dense, unthinned stands may enable Callitris to persist beneath dense Eucalyptus regeneration. Nevertheless, Callitris seedlings growing with dense Eucalyptus seedlings have a longer primary juvenile period than seedlings in sites with fewer seedling or adult eucalypts, which places these latter stands at greater risk of mortality in future fires and greater risk of browsing in the meantime.
Some Callitris endlicheri may begin to produce viable seed by seven years of age but may take up to 15 years or more. It will take longer to establish an adequate seed bank to respond to future fire events. There is a direct and strong relationship between plant size and primary juvenile period. Size is a better indicator of fecundity than tree age.
An extended juvenile period heightens the susceptibility of regenerant seedlings to browsing damage (or removal). Two fires in quick succession will cause local extinctions of Callitris endlicheri. Long intervals between fires favour dominance by Callitris endlicheri.
After fires, there is competition between Callitris seedlings, Eucalyptus seedlings and resprouting Eucalyptus in mixed stands. Mixed stands are more prone to local extinction of the Callitris component than are pure stands of Callitris because Callitris grow more slowly in mixed stands.
Under all but extreme conditions, fires are more likely to kill small than large Callitris. Consequently, if managers aim to maintain Callitris populations, then fires of moderate to high intensity should be excluded from areas containing young Callitris and moderate to dense Eucalyptus regeneration for longer than areas containing young Callitris amid sparse Eucalyptus regeneration. High basal area of Callitris reduces fire intensity in mixed Eucalyptus–Callitris stands. Consequently, over the longer term, protection of Callitris populations may reduce forest flammability and potential fire intensity.
Browser exclusion fencing may be of some value, particularly where browser populations are high.
It is concluded that fire response for Callitris endlicheri in this study can be extrapolated to a number of other Callitris species in parts of Victoria. 

Introduction
Black Cypress-pine Callitris endlicheriis an Australian 
native conifer, moderately common on hilly sites in south-eastern Australia. An open conical tree, growing to a maximum height of around 20 metres, it occurs along Australia’s east coast, from south-eastern Queensland to north-eastern Victoria. Callitris species are fire sensitive (Bowman and Harris 1995). In general, Callitris species are relatively drought tolerant, often occupying warmer and drier niches on relatively shallow stony soils and steep slopes 
(e.g. C. columellaris; Lindsay 1967, Attiwill and Clayton-Green 1984, Clayton-Green and Ashton 1990) and extending well into central Australia. Populations of C. endlicheri occur both as co-dominants with various Eucalyptus species and as the sole dominant in other sites. Several C. endlicheri populations in north-eastern Victoria were affected by bushfire in 2003 in Chiltern-Mt. Pilot National Park and in 2009 in the Flagstaff Range immediately south of Beechworth.
Individuals of Callitris species are susceptible to even low intensity fire and many plants are killed by moderate to severe fires. They have little capacity to resprout and often regenerate solely from seed (Walker and Green 1979; Bowman et al. 1988a; Bowman and Harris 1995; Keith 1996; Bradstock and Cohn 2002; Harris 2002; Thompson and Eldridge 2005). Historical and current fire regimes are thought to have influenced the distribution and extent of several Callitris species (C. glaucophylla, Bowman and Latz, 1993; C. intratropica R. T. Baker and H. G. Smith, Bowman and Panton 1993, Bowman et al. 2001). Due to adult sensitivity to fire and subsequent recruitment from seed, fires at short intervals are perceived to be a significant threat to the long-term persistence of Callitris (Keith 1996; Gill and McCarthy 1998; Bowman et al. 2001).
Several species of Callitris (e.g. intratropica, glaucophylla, rhomboidea and oblonga A. Rich and Rich) regenerate successfully in inter-fire intervals (cf. obligate bradyspory) on sites free from major disturbance. This produces mixed-age stands (Hahs et al. 1999, Bowman and Harris 1995). However, disturbance (e.g. grazing), may result in large lags between periods of successful recruitment, resulting in stands with one or two age classes (Sandell et al. 2002; Thompson and Eldridge 2005; Murdoch 2006; Briggs et al. 2008). Previous studies have shown varying levels of serotiny in Callitris species (C. verrucosa, strong serotiny, Bradstock and Cohn 2002). The level of serotiny in C. endlicheri is unknown.
Seedling emergence in C. endlicheri varies according to site, season of burn and moisture. There are interactions among these factors; for example, significant differences in seedling emergence occurred at different sites in different seasons (Knox and Clarke 2006). Seedling emergence was significantly greater in low and moderate intensity burnt sites, compared with unburnt areas (into which seed was sown), indicating the facultative influence of fire (ibid.). MacKenzie and Keith (2009) described an adaptive management approach to a population of C. endlicheri affected by unplanned fire and threatened by deer browsing. They concluded that low cost measures of seedling protection were effective, although permanent fencing for deer exclusion was likely to be more beneficial in the long-term.
Callitris recruitment is affected by factors other than fire, notably rainfall and browsing. For example, variations in spring and summer rainfall are thought to be prime influences on seedling mortality of C. endlicheri; if rainfall is adequate, then mortality is low after the first year (Elsey 1957). Browsing pressure, particularly from rabbits, has been shown to limit recruitment success in C. glaucophylla (Austin and Williams 1998; Thompson and Eldridge 2005) and in Callitris gracilis (Sandell et al. 2002; Murdoch 2006). Previous reports have highlighted the need for grazing exclusion at the seedling stage (Carey et al. 2003; MacKenzie and Keith 2009; Cochrane and McDonald 1966; Scott 1992; Sandell 2003; Callister 2004). MacKenzie and Keith (2009) described an adaptive management approach to a population of C. endlicheri affected by unplanned fire and threatened by deer browsing. They concluded that low cost measures of seedling protection were effective, although permanent fencing for deer exclusion was likely to be more beneficial in the long-term.
The questions we aim to address are:
•	How does the response of C. endlicheri to fire vary with fire frequency?
•	Is the persistence and recovery of C. endlicheri at a site affected by competition with associated eucalypts? Are mixed stands (Eucalyptus and Callitris) more prone to Callitris extinction or decrease after fires compared to pure stands of Callitris?
•	Are the structure and fire responses of the Flagstaff Range C. endlicheri population (a small mixed stand) comparable with the population structure and post-fire responses of the much larger stands north of Beechworth, around Mt. Pilot? How far can we extrapolate results from study of the Mt. Pilot population?
•	Does exclusion fencing (or other browsing reduction) increase the likelihood of Callitris seedling survival and growth?
•	How many years before C. endlicheri produce seed? Is tree size a better indicator of fecundity than tree age?
This report is presented as three sections:
1.	Section 1 – Flagstaff Range and New Data. New data collected for the current study utilizing plots established straight after the 2009 fire in the Flagstaff Range, south of Beechworth, and other data collected from a site in the Warby Ranges, north-west of Wangaratta.
2.	Section 2 – Mt. Pilot and new analyses of existing data. Analyses of data collected by staff and students of Charles Sturt University from sites established after the 2003 fires in the Mt. Pilot area. These sites have been revisited and monitoring data collected (almost) annually up to, and including in, 2010.
3.	Section 3 – Summary of Management Implications. A summary discussion of the management implications of the whole study, incorporating findings from the data newly collected specifically for this study and from the data collected from the Mt. Pilot longer-term monitoring sites.

Section 1 – Flagstaff Range and new data
1.1	Methods
1.1.1	Study site: Flagstaff Ranges
A small population of C. endlicheri exists in the Flagstaff Range State Forest, south of Beechworth, in north-eastern Victoria. Mean annual rainfall at Beechworth is 949 mm (Beechworth [station 82001]; Bureau of Meteorology 2010) and the surface geology of the area is Ordovician sedimentary. The dominant eucalypts at the study site are Eucalyptus blakelyi (Blakely’s Red Gum) and Eucalyptus polyanthemos (Red Box), with Eucalyptus goniocalyx (Long-leaf Box) also common in the vicinity.
A one hectare (approximately) patch of C. endlicheri, and several large C. endlicheri individuals were burnt in the Beechworth-Mudgegonga ‘Library Road’ fires in February 2009. The 2009 fire perimeter encloses 33,577 ha and was described as a “hot burn” by local land managers. This was evidenced by E. polyanthemos re-sprouting only from ground-level (Figures 1, 2). Considerable erosion occurred post-fire; local land managers commented that “the soil was a metre deep across the main road” below the site (Figure 3).
Grazing pressure was identified as a post-fire threat. Three grazing exclosures were established in 2009, in the large burnt C. endlicheri patch. One large individual tree, which had fallen, was also fenced. This work was led by local Department of Sustainability and Environment staff Sue Berwick and Glen Johnson. The exclosures were designed to exclude rabbits, goats and macropods, with standard wire mesh to 1.8 m high. Due to the nature of the rocky site conditions, mesh could not be buried in the soil profile but was placed so as to minimize the opportunity for rabbits to burrow under the mesh. After one year, the exclosures showed no sign of entry by any mammalian browsers. The exclosures were approximately rectangular in shape, their long axes aligned with the contour:
•	Exclosure 1 : 20 m × 13 m × 22 m × 13 m
•	Exclosure 2 : 20 m × 16 m × 20 m × 15 m
•	Exclosure 3 : 15 m × 14 m × 10 m × 13 m
Figure 1. Flagstaff Range, E. polyanthemos resprouting from lignotubers at or below ground level, all C. endlicheri dead; 
eight months post-fire.
Figure 2. Flagstaff Range, corner of Exclosure 1 showing C. endlicheri, cones and intact small branches.
Figure 3. Flagstaff Ranges Exclosure 2, 100% C. endlicheri mortality as well as bare soil and runoff issues at the site; eight months post-fire.
1.1.2	Study site: Mt. Pilot
A long-term study of C. endlicheri is underway in Chiltern-Mt. Pilot National Park, led by Ian Lunt at Charles Sturt University, Albury. The Eldorado fire of 2003 burnt 10 000 ha of the Chiltern-Mt. Pilot National Park. Since then, data on C. endlicheri demography have been collected annually, including measurements of seedling height, ‘health’ and density, as well as growth of coppicing eucalypts. In May 2010, collection of data on C. endlicheri seed cone production began. Demographic data on coincident eucalypts and groundcover have also been collected (Figure 4).
Figure 4. Chiltern-Mt. Pilot National Park, 2010; burnt in 2003. C. endlicheri showing strong seedling recruitment (this area was dominated by C. endlicheri before the fire).
1.1.3	Study design
Basic demographics
At the Flagstaff Range site, three 10 m × 10 m sample plots were established inside and outside the larger exclosure, creating six plots in total. Plots were permanently marked with metal stakes (star pickets) (Figure 5).
Within each plot the diameter over bark at breast height (dbh) was measured for each tree and the pre-fire stratum (e.g. suppressed, dominant) and post-fire status (e.g. resprouting, consumed) was assessed for each tree. The location of eucalypt coppice (arising from tree base, stem or coppice [arising from tree base, stem or branches]), maximum height and diameter of basal coppice were also measured.
Figure 5. Marking stake for permanent monitoring plot at Flagstaff Range.
Seedling density and growth
Ten 1 m × 1 m quadrats were haphazardly placed within each large quadrat. The number of seedlings and height of each seedling were recorded, along with an assessment of visible browsing impact (Figure 6). Cover of eucalypt coppice, other vegetation cover (grasses, herbs, shrubs and mosses), litter cover and substrate (rocks and bare ground) cover were all estimated.
The differences in seedling height and density inside and outside the exclosure fences were investigated using a t-test (unequal variance, two tails) in Microsoft Excel 2003.
To facilitate comparison of results, the experimental design for basic demographics and seedling density and growth was consistent with the methods used at Chiltern-Mt. Pilot National Park. However, there remained some clear differences between these two major sites: the exclosures at the Flagstaff Range cover a substantial part of the old burnt C. endlicheri population, while Chiltern-Mt. Pilot encompasses a much larger and more varied population, only part of which has been sampled.
Figure 6. Callitris endlicheri seedling affected by browsing.
Finally, 25 seedlings in each 100 m2 plot at the Flagstaff Range were individually tagged and numbered so that their fates can be monitored over time (Figure 7). For future survey, seedlings may be easily relocated using a metal detector.
Figure 7. Tagged C. endlicheri seedling.
Dendrochronological approach to demographics
Species of Callitris have elsewhere been indicated as highly suitable for demographic studies, as it has been assumed or determined that at least some of the species consistently accrue annual tree rings (Pearson and Searson 2002; Baker et al. 2008). To determine if C. endlicheri accumulates annual tree rings, a small sample of trees of known age was taken from the Warby Ranges in the Warby-Ovens National Park. A plantation of C. endlicheri had been established by the Forestry Commission in the mid-1950s, prior to park declaration (to assess the silvicultural prospects for 
C. endlicheri in the Warby Ranges). Callitris endlicheri is 
not indigenous to the Warby Ranges, where C. glaucophylla is locally common. These C. endlicheri trees were predicted to have c. 60 tree rings, assuming annual tree ring formation. If tree ring accrual proved to be annual, or even tied to a consistent conversion factor, then tree ring counts on C. endlicheri elsewhere could be used to determine the ages of other forest stands containing C. endlicheri.
Four stem sections were taken from C. endlicheri in the Warby Ranges plantation. These sections were prepared using standard dendrochronological procedures (Stokes and Smiley 1968), they were sanded using increasingly fine sandpaper (180 – 600 grit) to remove abrasions from the wood surface and produce a clear view of the wood anatomy. Sections were then scanned at 1800 dpi resolution using a ScanMaker 1000XL scanner (Microtek International Inc.) and visually crossdated using WinDendro (Regent Instruments, Canada) image-analysis software.
Fecundity
The timing of this study, 21 months post-fire, did not allow measurement seed production at Flagstaff Range. Data collected at Chiltern-Mt Pilot National Park show seed production is beginning now at seven years post fire (refer to Section 2). Data relevant to cone production collected at Chiltern-Mt. Pilot National Park were tree height, height of cones, location of cones, diameter of cone and whether the cone was intact, damaged, open or closed.
1.2	Results
1.2.1	Demographics
The pre-fire stand of C. endlicheri at Flagstaff Range was dominated by stems in the 10 to 15 cm dbh size class, although trees were as large as > 30 cm dbh (Figure 8). All burnt stems appeared dead.
The basal area of C. endlicheri within each plot varied, but was consistently greater than Eucalyptus basal area (Figure 9). The unfenced plot 1 (U1) had a considerably lower basal area of C. endlicheri. However, two large (approximately 20 cm dbh) C. endlicheri occurred immediately outside plot U1. It is likely that these C. endlicheri outside the plot, particularly upslope, influenced seed rain.
Figures for basal area should be considered minimum estimates, as it was not uncommon for pre-fire trees to have been completely consumed by the fire (i.e. we observed Eucalyptus coppice growing where there was no burnt trunk present) and hence impossible to incorporate into basal area estimates.
The predominant post-fire response of Eucalyptus was coppice (basal re-sprouting). Epicormic sprouting (from the trunk or branches) was not seen at the Flagstaff Range site (see Figures 1 and 3). The mean height of basal coppice was 2.1 m (standard deviation 0.8 m). Eucalyptus seedlings were scarce; a total of two eucalypt seedlings were recorded for all the plots.
Figure 8. Size structure (dbh) of burnt/ pre-fire C. endlicheri at Flagstaff Range.
Figure 9. Total basal area of C. endlicheri and Eucalyptus spp. at Flagstaff Range plots (10 m × 10 m).
1.2.2 	Seedling density and growth
Seedling density (C. endlicheri) was apparently greater inside the exclosures compared with outside, but this apparent difference was not statistically significant (t-test; P = 0.219) (Figure 11). Whether a larger sample size would show such a difference is undetermined. There was no significant difference in seedling height inside and outside the exclosures (t-test; P = 0.185) (Figure 12). Distribution of seedlings within each plot was patchy. There was evidence of considerable runoff and erosion occurring in U2, leaving much of the surface devoid of organic litter and with exposed rocks (Figure 10).
Seedlings appeared to be associated with (micro-)sites with lower bare ground and greater cover of ground plants (Figure 13).
Figure 10. Exposed hill slope, organic litter and finer-grained surface soil removed by heavy storms soon after the 2009 fire, Flagstaff Range.

Figure 11. Mean density of seedlings inside and outside exclosures, Flagstaff Range (mean ± one standard deviation).
Figure 12. Mean height of seedlings inside and outside exclosures, Flagstaff Range (mean ± one standard deviation). 
Figure 13. Sub-plot ground cover according to number of seedlings, Flagstaff Range (mean ± one standard deviation).
1.2.3	Comparison of Flagstaff Ranges and Chiltern-Mt. Pilot
Callitris endlicheri seedling recruitment at Flagstaff Range after the 2009 fire was compared with the 2004 C. endlicheri recruitment at Chiltern Mt. Pilot. The first data collections for these sites occurred at 21 months (Flagstaff Range) and 16 months (Chiltern-Mt. Pilot) post-fire.
Seedling density at Flagstaff Range varied from 0.2 to 3.3 seedlings/m2 across the six plots sampled (Figure 14). At Chiltern-Mt. Pilot, seedling density ranged from 0 to 7.4 seedlings/m2 in 2004, with a mean seedling density of 3.0 seedlings/m2 (fenced) or 3.5 seedlings/m2 (unfenced) across three sites, each with one fenced and one or two unfenced plots. 
Mean seedling height was slightly greater at the Flagstaff Range site, mean height of seedlings 18.2 cm (fenced) and 11.5 cm (unfenced), compared with Chiltern Mt. Pilot in 2004, 12.8 cm (fenced) and 10.5 cm (unfenced) (Figure 15).
Figure 14. Mean density of seedlings inside and outside fences at Chiltern-Mt. Pilot, according to year (mean ± one standard deviation).
Figure 15. Height of seedlings inside and outside fences at Chiltern-Mt. Pilot, according to year (mean ± one standard deviation).
Dendrochronological approach to demographics
Four stem sections were taken from C. endlicheri at the Warby Ranges plantation, their attributes are summarised in Table 1. 
Tree no.	Diameter at sample height (cm)	Height of sample (cm)	Tree height 
(m)	Number of tree rings	
1	38.4	26	16.2	60	
2	39.2	30	15.5	57	
3	34.1	20	13.8	47	
4	18	38	11.9	57	

Although tree ring chronologies measured along different radii within the same tree were successfully visually crossdated (‘matched’), there was uncertainty as to what constituted an annual tree ring. The wood anatomy of sampled C. endlicheri typically showed around 15 (or 25%) unclear tree rings within each chronology (i.e., faint coloured tree rings and or tree rings lacking clear gradation from large to small diameter tracheids), and ‘double rings’ were common – these are likely composed of one false ring and one annual ring, but are difficult to differentiate from small rings (Figure 16). However, counts of putative tree rings approximated expected number of tree rings if tree rings were produced annually (i.e., 60). Working with such tree ring chronologies is possible but requires a significant time investment, and ideally would be carried out on stem sections rather than increment cores. 
Figure 16. Double rings (left) and poorly differentiated rings (right)
1.2.4 	Fecundity
None of the C. endlicheri seedlings at Flagstaff Range supported mature or immature cones during the survey in November 2010. However, there were multiple records of trees with cones at Chiltern-Mt. Pilot in 2010 (seven years post fire), predominantly on seedlings taller than 200 cm (Figure 17). There was considerable variation among cone-bearing seedling heights at Chiltern-Mt. Pilot, ranging from 140 cm to 280 cm.
The cones at Chiltern-Mt. Pilot varied in size and reproductive status. Most cones were intact (undamaged, not forcibly opened) and closed, although many cones were very small (<15 mm diameter) (Table 1, Figure 18).
Table 1. Indicators of cone health/ viability, and number of individuals.
Cone status	Number of cones	
Intact, closed	359	
Intact, open	4	
Damaged, closed	4	
Damaged, open	2	
Figure 17. Number of cones in each cone size class at Chiltern-Mt. Pilot, 2010.
Figure 18. Old fire scar on a veteran C. endlicheri, indicating survival from a previous fire, Flagstaff Range. 
1.3 	Discussion
As a general rule, individuals of Callitris species are killed by fire and recruit only from seed. Occasional individuals within an otherwise burnt stand may escape the fire due to site-specific factors and very large veterans may develop a zone of reduced fuel in their immediate surrounds, thus heightening their chances of escaping fire. But only a very small proportion of individuals within a fire perimeter escape being killed. Post-fire, seedlings are particularly vulnerable to threats such as grazing, drought and repeat fire. Hence, conditions in the post-fire period are a critical determinant of the obligate-seeding fire-sensitive species persistence at a site.
A population of Callitris endlicheri in the Flagstaff Range was burnt in the Black Saturday fires in 2009. Fenced exclosures were established to protect the seedlings from grazing. Detailed monitoring of the fire-affected population was undertaken 21 months post-fire. Seedling heights and densities were measured, and individual seedlings were tagged to monitor long-term survival, inside and outside fences. Monitoring can be repeated in coming years, as the sites are well marked and ‘permanently’ marked. In this report, these first data from the Flagstaff Range C. endlicheri population are compared with data from a nearby population of C. endlicheri at Chiltern-Mt. Pilot (burnt in 2003 and monitored from 2004 until present).
Figure 19. Old fire scar on a veteran C. endlicheri, indicating survival from a previous fire, Flagstaff Range.
1.3.1 	Impacts of browsing
At Flagstaff Range, fencing protection from grazing did 
not lead to statistically significant differences in 
C. endlicheri seedling height or density, when regenerants within exclosures were compared with regenerants close by, but outside, the exclosures. However, there was evidence of grazing impacts at the site, such as malformed seedling regenerants, which were interpreted as having been browsed (Figure 20). Local land managers suggested the main browsers were rabbits and macropods (Eastern Grey Kangaroo Macropus giganteus and Swamp Wallaby Wallabia bicolor).
The results from the Flagstaff Range population can be usefully compared with those from the long-term 
C. endlicheri study sites at Chiltern-Mt. Pilot. At the latter site, fencing was associated with significantly taller seedling heights, but this difference became notably more pronounced from the third year post-fire. That the difference in heights was not significant until some years after the fire may reflect the variability of the C. endlicheri population at Chiltern-Mt. Pilot, but is more likely attributable to the difference in grazing pressure among sites and seasons. At Beechworth, annual rainfall was slightly above average from 2003–2005 (965–1215 mm/yr), very low in 2006 (413 mm) and ca. 80% of average from 2007–2009 (755–790 mm) (Bureau of Meteorology 2010).
Figure 20. Seedling regenerants, C. endlicheri, browsed (outside exclosures) to the left, unbrowsed (inside exclosures) to the right; Flagstaff Range.
In places accessible to browsers, low values of the parameter ‘seedling height’ may be attributed to (a) recent germinants, (b) older germinants that are suppressed (by poor growing conditions at a particular site) and (c) germinants that have been browsed. It is not possible to disentangle these factors completely (although see Section 2). Seven years after fire, seedlings at some Chiltern-Mt. Pilot sites are still being maintained below browsing-accessible height (< 50 cm) while at other sites they are taller than two metres.
The influence of browsing on Callitris recruitment success has been explored in several previous studies. Browsing by domestic stock and rabbits was documented as suppressing Callitris gracilis recruitment in the mallee (Zimmer 1944; Cochrane and McDonald 1966; Sandell et al. 2002). In central-western NSW woodlands, Leigh et al. (1989) found Callitris glaucophylla seedlings appeared only in rabbit exclosures, an observation supported by Scott (1992) in the south of the state and by Thompson and Eldridge (2005) and Briggs et al. (2008) from a more regional perspective. Cheal (2004) found that the effect of goat browsing on Callitris verrucosa in the Mallee was severe, with all accessible foliage browsed. Browsing can be an important limitation to Callitris seedling establishment and growth.
Seedling densities inside and outside fences at Chiltern-Mt. Pilot are not significantly different even at seven years post-fire, indicating that while grazing influences height, it has not, as yet, influenced mortality rates. Nevertheless, shorter seedlings, as well as being susceptible to browsing over an extended period, experience greater competition for light and other resources (such as soil moisture), with resprouting eucalypts and other shrubs. In effect, a positive feedback loop is maintained, whereby the smaller (lower height) Callitris germinants are suppressed by interspecific competition and kept small. This is in line with the ‘tortoise and hare’ model of conifer-angiosperm interaction proposed by Bond (1989).
Seedling height is correlated with cone production. Data from Chiltern-Mt. Pilot indicate that the proportion of individuals with cones increases after trees reach around two metres tall. Apart from grazing, growth is influenced by environmental factors, specifically rainfall, temperature, soil nutrients, sunlight and competition for these resources (Oliver and Larson 1996). The minimum time to C. endlicheri cone production (or height of two metres), at Chiltern-Mt. Pilot, was seven years. However, some trees may take much longer than this to reach two metres, or even to simply exceed rabbit browse height. Furthermore, cones take additional time to mature; the vast majority of the cones at Chiltern-Mt. Pilot were small and closed.
1.3.2	Impact of environmental conditions
Previous studies suggest that rainfall is an important determinant of seedling survival and growth of some Callitris species. In the nearby Warby Ranges; the majority of seedling mortality in C. glaucophylla, is thought to occur in the first year (Elsey 1957). Bradstock and Cohn (2002) noted that post-fire rainfall was important for Callitris verrucosa seedling survival and establishment. Moreover, Read (1995) highlighted the need for long periods of above-average rainfall for successful post-fire recruitment in Callitris glaucophylla and Harris (2002) reported episodic regeneration in C. glaucophylla requiring synchrony between a seed supply and an extended period of above-average rainfall.
The first measurements of the C. endlicheri population at Flagstaff Range were from 21 months post-fire. Rainfall was below average for the first 12 months post-fire (755 mm in 2009 cf. average 949 mm), so it is possible that some drought-induced mortality occurred and was not measured. However, rainfall in the second year post-fire is on track to be considerably above average (1247 mm; November 2010). Mortality will be able to be directly measured in this project using permanently tagged seedlings (cf. indirect measurement by changes in seedling density).
Callitris endlicheri seedlings at Flagstaff Range were commonly found in ‘clusters’ associated with coarse woody debris and litter (Figure 20). Litter is thought to protect seeds from flux in temperature and moisture (Adams 1999; Bonnet et al. 2005; Harris et al. 2003), and from predators such as ants (Andersen 1988) and rodents (Myster and Pickett 2003). However, at this site, protection from erosion and runoff (surface roughness) that is provided by coarse woody and finer debris may be the most important factor. High intensity fires can increase erosion and runoff by reducing ground cover and altering soil properties (DeBano et al. 1998, Wondzell and King 2003). Coarse woody and other lighter debris can slow this runoff, capturing litter and seeds (Ferran and Vallejo 1992; Rice 1993).
Figure 21. Callitris seedlings clustered in litter, Flagstaff Range.

Section 2 – Mt. Pilot and new analyses of existing data: The tortoise and the hare? Post-fire regeneration in mixed Eucalyptus-Callitris forest
Introduction
A principal goal of vegetation ecology is to understand the factors that influence vegetation patterns and dynamics. In 1989, William Bond developed a general model to interpret competitive interactions among two groups of seed plants: the gymnosperms and angiosperms. Bond’s (1989) ‘slow seedling’ or ‘tortoise and hare’ hypothesis stated that because gymnosperm seedlings had lower growth rates than angiosperm seedlings due to architectural constraints, gymnosperms were largely restricted to low-productivity ecosystems where they escaped competition from vigorous, fast-growing angiosperms. By contrast, in productive ecosystems, competition from angiosperms would suppress gymnosperm growth rates, leaving gymnosperm seedlings vulnerable to processes that cause size-dependent mortality, such as drought, herbivory and fire. In some instances, gymnosperm decline would be hastened if angiosperms promoted adverse disturbances, for example, where grasses fuelled fires that killed gymnosperm seedlings (Bond and Scott 2010). Cast in the language of Grime’s (2001) plant strategy scheme, gymnosperms were viewed by Bond (1989) as ‘stress tolerators’, poorly equipped to regenerate and persist in productive environments dominated by more ‘competitive’ angiosperms. 
Our understanding of the physiological mechanisms underlying low growth rates of gymnosperm seedlings has since been refined (Becker et al. 1999; Becker 2000; Lusk 
et al. 2003, Brodribb et al. 2005), and Bond’s ‘slow seedling’ model may be viewed within a broader plant leaf economics spectrum, in which relative growth rate (RGR) is related to leaf longevity and specific leaf area (Comelissen et al. 1996; Reich et al. 1999; Wright et al. 2004). Gymnosperms characteristically have long-lived leaves of low SLA, which lead to lower RGRs than many, but not all, angiosperms (Reich et al. 1999; Lusk et al. 2003).
The most widespread and abundant genus of gymnosperms in Australia is Callitris (Cupressaceae), which occurs in tropical, sub-tropical, arid, semi-arid, Mediterranean and temperate regions (Bowman and Harris 1995). Callitris dynamics have received considerable attention from fire ecologists as Callitris are often killed by fire and usually do not resprout after being subjected to 100% leaf scorch (Lacey 1973; Bradstock and Cohn 2002, Russell-Smith 2006). Consequently, population dynamics are highly sensitive to changes in fire regimes (Bowman and Panton 1993; Bradstock et al. 2006; Prior et al. 2010). Surprisingly, Bond’s (1989) model has never been referred to in studies on Callitris ecology. This may be because few studies have documented interactions between Callitris and other woody species (e.g. Clayton-Greene 1981; Clayton-Greene and Ashton 1990; Bowman et al. 1988b), even though Callitris occur in heathlands, woodlands and forests dominated by Eucalyptus and other woody plants (Bowman and Harris 1995). In savannah and arid woodlands, fire regimes and Callitris dynamics are regulated by dominant grasses rather than woody plants (Bowman et al. 1988b; Bradstock and Cohn 2002). Indeed, we know of only one study (an unpublished seedling pot trial) that has documented competitive interactions between Callitris seedlings and other woody taxa (Clayton-Greene 1981).
This paucity of information raises the question, to what extent do interactions with woody angiosperms influence Callitris dynamics in productive forest ecosystems? Under Bond’s (1989) model, inter-specific interactions could influence the ability of non-resprouting Callitris to persist in ecosystems dominated by flammable, resprouting angiosperms. In this study, we attempt to address this issue by asking: to what extent are post-fire recruitment patterns in a mixed Callitris-Eucalyptus forest in a relatively high rainfall region (ca. 850 mm mean annual rainfall) consistent with Bond’s slow seedling hypothesis? We discuss the implications of these patterns for species co-existence and fire management. Our study is observational rather than manipulative, which means that while we can assess whether patterns are consistent with Bond’s hypothesis, we cannot be definitive about the mechanisms that underlie observed patterns.
2.1 	Methods
2.1.1 	Study area
The study was conducted in Chiltern–Mt. Pilot National Park in north-eastern Victoria, Australia. Mean annual rainfall in the study area is approximately 850 mm, based on data from nearby Beechworth (960 mm) and Beechworth Woolshed rainfall gauges (770 mm; Bureau of Meteorology 2010). The underlying geology is Devonian granite and the topography is moderately to steeply undulating (Parks Victoria 2008). The area supports dry sclerophyll forests dominated by Eucalyptus macrorhyncha F.Muell. ex Benth, E. goniocalyx F.Muell., E. polyanthemos Schauer and E. blakely Maiden i, with patches dominated by Callitris endlicheri. Most Callitris-dominated stands are small (< 1 ha) and in close proximity to rocky outcrops (Watson 2004).
In January 2003, 7300 ha of the reserve burnt in a high intensity bushfire (Watson 2004). In July 2003, two 10 × 10 m fenced plots were erected in each of three burnt Callitris stands near Mt. Pilot to assess browsing impacts on Callitris seedlings. Post-fire vegetation monitoring began in autumn 2004. Twelve stands of Callitris were selected within a 2.2 km radius of the Mt. Pilot summit (36°15’06” S, 146° 40’13” E). All 12 sites were burnt at high intensity, as evidenced by complete mortality of pre-fire Callitris and resprouting of surviving Eucalyptus from basal coppice rather than from epicormic buds on trunks or branches. Six stands, including the three stands containing fenced plots, were dominated by mature C. endlicheri, presumed to have recruited in the late 1800s, with sub-dominant Eucalyptus. The other six stands were dominated by Eucalyptus above smaller Callitris, which were presumed to have recruited after 1950.
Permanently marked 100 m2 (10 m × 10 m) plots were established at each site. Paired unfenced plots were established at the three fenced sites, giving four plots in total at these sites (plus an extra unfenced plot in one large stand), and two unfenced plots were established in the nine stands without fences. Pre-fire stand structure was estimated in autumn 2004 by measuring all dead and resprouting trees in each 100-m2 plot. Small saplings that were totally incinerated would not have been detected. 
The height, number of stems, and girth over bark at breast height (GOBBH) of the largest stem was recorded annually for all coppicing Eucalyptus in each 100-m2 plot. For clarity, all post-fire seedling recruits are called ‘seedlings’ here, even though many had grown tall (i.e. to ‘sapling’ size) by the end of the monitoring period. The species identity, height and GOBBH of all post-fire seedlings were assessed annually in 10 (in 2004) and 20 (2005-2010) randomly placed 1 m2 subplots within each 100 m2 plot. These subplots were re-randomized each year. GOBBH was recorded as 0.1 cm if plants were < 1.3 m tall. Sampling was conducted in autumn 2004 to 2010, but only two sites were sampled in 2009, due to inclement weather. At Beechworth, annual rainfall was slightly above average from 2003–2005 (965–1215 mm/yr), very low in 2006 (413 mm) and ca. 80% of average from 2007–2009 (755–790 mm; Bureau of Meteorology 2010).
2.1.2	Data analysis
Linear mixed models were used to examine:
1.	The relationship between initial seedling density (including live and dead seedlings in 2004) and the pre-fire basal area of each genus;
2.	The effects of fencing and time on the density and height of live seedlings of each genus; and
3.	Associations between seedling height in 2010 and (a) the pre-fire basal area of each genus, (b) the density of competing seedlings in 2010, and (c) the basal area of resprouting Eucalyptus in 2010.
The influence of fencing on seedling heights and densities was assessed using data from the three sites with fenced and unfenced plots only. In each case, year, fencing treatment, basal area (at the plot scale), and seedling density in subplots were included as fixed effects, and nested sites, plots and subplots were incorporated as random effects. Where necessary, density, height and basal area data were log transformed to meet the assumption of constant variance. F-tests were used to investigate the significance of individual model terms. Analyses were undertaken in GenStat (Ver. 13). In addition, t-tests were used to compare: (1) the height of Eucalyptus and Callitris seedlings in 2010, (2) the proportion of seedlings in fenced and unfenced plots with evidence of browsing in 2010, and (3) the mean height of seedlings in fenced and unfenced plots in 2010. Few Callitris seedlings produced seed cones by 2010. Consequently, associations between the density of Callitris and Eucalyptus seedlings versus the number of Callitris seedlings bearing seed cones and the number of cones produced were analysed at the plot scale, using Spearman’s rank correlation coefficients. 
2.2 	Results
2.2.1	Seedling density and mortality
Callitris and Eucalyptus seedlings both regenerated at high density after the 2003 fire. On average, there were 5.8 Callitris seedlings/m2 and 2.8 Eucalyptus seedlings/m2 in 2004, 16 months after the fire. The initial, post-fire density of Callitris seedlings was significantly and positively associated with the pre-fire basal area of Callitris (P = 0.031). After accounting for the association of Callitris seedling density with Callitris pre-fire basal area, the association with Eucalyptus pre-fire basal area was not significant. By contrast, the initial density of Eucalyptus seedlings was not significantly associated with the pre-fire basal area of either genus (P = 0.333 and 0.717 for Eucalyptus and Callitris, respectively).
Mortality rates after the first monitoring event were extremely low for both genera. The mean density of live Callitris seedlings apparently declined from 5.2 to 3.7 seedlings/m2 from 2004 to 2010, however this change was not statistically significant (at P< 0.05). The mean density of Callitris seedlings did not change significantly over time (P = 0.783) nor did it differ significantly across fencing treatments, when all plots (including all unfenced plots) were compared (P = 0.348). Similarly, when data from only the three sites with fenced plots were analysed, the density of Callitris seedlings was not significantly associated with year (P = 0.723), fencing (P = 0.392) nor the year*fencing interaction (P = 0.945; Fig. 22a).
By contrast, there was a significant decline in the density of live Eucalyptus seedlings over the same period. Across all sites, mean (back-transformed) density declined from 2.8 to 1.2 seedlings/m2. When data from all plots were analysed, the density of Eucalyptus seedlings differed significantly among years (P< 0.001) but not among fencing treatments (P = 0.122) or with the year*fencing interaction (0.348). When data from only the three sites with fenced plots were analysed, the density of Eucalyptus seedlings was not significantly affected by year (P = 0.224), fencing (P = 0.428) nor year*fencing interaction (P = 0.947; Fig. 22b).
2.2.2 	Seedling growth rates
Callitris seedlings were, on average, shorter than Eucalyptus seedlings throughout the survey period (Figure 23). In 2010, the mean height of Eucalyptus seedlings was over twice that of Callitris seedlings (184 cf. 84 cm; t-test, P< 0.001), and the tallest Eucalyptus seedling was over twice as tall as the tallest Callitris seedling (max. height, 800 cf. 350 cm). In 2010, 30% of Callitris seedlings were < 0.5 m tall.
Figure 22. Predicted density of live (a) Callitris (mean ± standard error) and (b) Eucalyptus seedlings in fenced and unfenced plots (back-transformed mean ± standard error) after the 2003 fire at Mt. Pilot. 
Figure 23. Predicted mean height of (a) Callitris and (b) Eucalyptus seedlings in fenced and unfenced plots (back-transformed mean ± standard error).
2.2.3	Fencing effects
In 2010, it appeared that more Callitris seedlings showed evidence of browsing in unfenced than fenced plots (25% cf. 2% at the plot scale) although this difference was not significant at the P = 0.05 level (paired t-test, P = 0.09). Callitris seedlings grew taller in fenced than unfenced plots (Fig. 23a). The mean (back-transformed) height of Callitris seedlings varied significantly with year (P< 0.001) and fencing treatment (P = 0.007) with no significant year*fencing interaction (P = 0.198). In 2010, the mean height of Callitris seedlings in fenced plots was 145 cm compared to 116 cm in unfenced plots (t-test, P< 0.001). By contrast, only 5% of all Eucalyptus seedlings surveyed in 2010 (in all fenced and unfenced plots) displayed evidence of browsing. No Eucalyptus seedlings were browsed within the three fenced plots in 2010. Consequently, the height of Eucalyptus seedlings varied significantly with year (P = 0.002) but there was no significant fencing effect (P = 0.747) nor year*fencing treatment interaction (P = 0.558; Figure 23b). In 2010, the mean height of fenced and unfenced Eucalyptus seedlings was 226 cm and 245 cm respectively (t-test, P = 0.70).
2.2.4 	Factors associated with seedling height
The linear mixed model showed that the height of Callitris seedlings in 2010 was significantly and positively associated with fencing (P = 0.017), and negatively associated with the density of Eucalyptus seedlings (P = 0.006). After accounting for these terms, there was no significant association with (a) the density of Callitris seedlings, (b) the basal area of coppicing Eucalyptus, nor (c) the pre-fire basal area of Callitris or Eucalyptus (Table 2). The lack of association between Callitris seedling heights and the pre-fire basal area of either genus suggests that Callitris seedlings neither grew better nor worse in plots dominated by either genus before the fire.
In contrast, the height of Eucalyptus seedlings in 2010 was significantly negatively associated with Eucalyptus seedling density (P< 0.001) and positively associated with Callitris seedling density (P = 0.002) and the pre-fire basal area of Callitris (P = 0.053; Table 2), which indicates that Eucalyptus seedlings grew faster where Callitris dominated before the fire.
Table 2. Model statistics for linear mixed models describing the factors associated with Callitris seedling heights in 2010. Terms were individually removed from the full fixed model, d.d.f.= denominator degrees of freedom, numerator degrees of freedom = 1.
Fixed term	F. statistic	d.d.f.	Probability
(F pr)	
Eucalyptus density in 2010	7.6	419.5	0.006	
Callitris density in 2010	3.59	329.3	0.058	
Eucalyptus coppice basal area in 2010	2.58	27	0.108	
Fencing treatment	5.67	25	0.017	

Table 3. Model statistics for linear mixed models describing the factors associated with Eucalyptus seedling heights in 2010. Terms were individually removed from the full fixed model.
Fixed term	F statistic	d.d.f.	F pr	
Fencing treatment	0.73	29.5	0.401	
Log Callitris basal 
area in 2004	4.18	22.0	0.053	
Log Callitris density 
in 2010	9.70	257.5	0.002	
Log Eucalyptus density in 2010	11.25	251.5	<0.001	

2.2.5 	Seed cone production
In 2010, seven years after the fire, 2% of Callitris seedlings possessed seed cones. Seed cones were almost entirely restricted to the tallest seedlings. Thus, 83% of cones were on seedlings taller than 150 cm (Figure 24), and 23% of seedlings > 2 m possessed seed cones (n = 100). The shortest seedling with seed cones was 140 cm tall. Cone production varied from < 5% to almost 30% of Callitris seedlings at each plot.
In 2010, there was no significant correlation between the number of Callitris seedlings in each plot and either the number of Callitris seedlings bearing seed cones (Spearman’s rank correlation coefficient, rho = -0.030, d.f. = 29, P = 0.874) or the number of seed cones produced (rho = -0.039, P = 0.833). However, there was a significant negative correlation between the number of Eucalyptus seedlings in each plot and the number of Callitris seedlings bearing seed cones (rho = -0.454, P = 0.010) and the number of seed cones produced (rho = -0.448, P = 0.012). The total number of Eucalyptus and Callitris seedlings in each plot was positively correlated (rho = 0.380, P = 0.0352). Thus Callitris seedlings produced more seed cones in plots with fewer Eucalyptus seedlings.
Figure 24. The proportion of Callitris seedlings in different height classes that possessed seed cones in 2010. Only 19 seedlings were taller than 250 cm.
2.3 	Discussion
These results illustrate a number of patterns that are consistent with Bond’s (1989) slow seedling hypothesis:
1.	Eucalyptus seedlings grew faster than Callitris seedlings;
2.	Callitris seedlings grew faster, and produced seed cones sooner, in plots with fewer Eucalyptus seedlings; and
3.	Small Callitris seedlings growing beneath dense Eucalyptus seedlings remained vulnerable to browsing and burning for longer than tall Callitris seedlings in areas with fewer Eucalyptus seedlings.
Spatial variations in the growth rate of Callitris seedlings were not related to the suitability of sites to support Callitris, as many patches with small Callitris and dense Eucalyptus seedlings were dominated by mature Callitris before the 2003 fire. However, contrary to Bond’s (1989) theory, few Callitris seedlings died, so competition during the regeneration phase did not regulate co-existence. We expand on each of these points in the discussion below.
2.3.1 	Seedling growth rates
The lower growth rate of Callitris compared with Eucalyptus seedlings is consistent with the global trend for lower growth rates in gymnosperms than in sympatric angiosperms (Bond 1989; Reich et al. 1999; Lusk et al. 2003), and with pot and field trials in which planted Eucalyptus seedlings grew faster than Callitris seedlings (Clayton-Greene 1981; Allcock and Hik 2004). Apart from fencing, the factor most strongly associated with the growth rate of Callitris seedlings was the density of Eucalyptus seedlings. Callitris seedlings grew slowest where Eucalyptus seedlings were most abundant, and fastest where Eucalyptus seedlings were most sparse. Removal experiments are required to disentangle the effects of abiotic site factors and competition on Callitris growth rates. Nevertheless, the negative association suggests that competition from dense, tall Eucalyptus seedlings may have slowed the growth of smaller Callitris seedlings. The lack of a significant association between the growth rate of Callitris seedlings and the pre-fire basal area of Callitris indicates that sites with dense Eucalyptus seedlings and small Callitris seedlings were not unsuitable for Callitris growth and persistence; Callitris dominated some of these sites before 
the fire. . In contrast to savanna ecosystems, grasses had very low cover and biomass at Mt. Pilot, and grass competition is unlikely to have had a substantial impact on growth rates or survival of Callitris or Eucalyptus seedlings, except perhaps in the first year or two after fire.
Silvicultural trials have demonstrated that the growth rate of retained Callitris is enhanced when dense Callitris stands are thinned (Knott 1995; Ross et al. 2008). However, few studies have documented competitive interactions between Callitris and Eucalyptus. Clayton-Greene (1981) reported that Eucalyptus melliodora seedlings suppressed the growth of Callitris glaucophylla seedlings in a pot competition experiment. In a small thinning trial, Bowman et al. (1988b) found that Callitris grew fastest in treatments with the lowest representation of co-occurring Eucalyptus and Callitris, but unfortunately their results do not clearly differentiate the competitive effects that were exerted by the two genera.
2.3.2	Browsing damage
Results from the fencing trial indicate that slow-growing Callitris seedlings were vulnerable to browsing, and that browsing magnified the height difference between the two genera. However, this set-back was temporary rather than persistent. As time progressed, the height difference between fenced and unfenced Callitris seedlings diminished, perhaps because taller, older plants were less accessible to browsing animals. Nevertheless, a high proportion of Callitris seedlings at Mt. Pilot remains vulnerable to future damage by browsing animals and other disturbances.
The low level of mortality in grazed plots is likely to reflect low herbivore densities, as few large herbivores were observed in the first few years after the 2003 bushfire (I. Lunt, pers. observ.). In contrast, Mackenzie and Keith (2009) recorded high mortality of C. endlicheri seedlings in an area grazed by feral Rusa Deer (Cervus timorensis) in coastal NSW. Over 12 months, 98% of unprotected seedlings were browsed at least once, leading to a 59% decline in seedling density (Mackenzie and Keith 2009). Seedlings of the related species, Callitris glaucophylla, are known to be sensitive to repeated browsing by rabbits and sheep (Lacey 1972).
2.3.3	Seedling mortality
In contrast with Bond’s (1989) theory, Callitris populations did not decline markedly during the establishment period due to direct competition with angiosperms nor any other cause. We recorded no significant decline in the density of Callitris seedlings over six years, despite a high sampling intensity. By contrast, the density of Eucalyptus seedlings declined by 57% during the six-year period, consistent with many studies that have documented self-thinning in Eucalyptus stands after fire (Florence 1996). 
The stability in Callitris numbers was surprising, as small seedlings are usually highly susceptible to mortality arising from insufficient resources and disturbances, and the survey period included years with marked rainfall deficiencies. By contrast, Mackenzie and Keith (2009) found that the density of protected (unbrowsed) C. endlicheri seedlings declined by 19% within a 12-month period, from two to three years after fire. Initial seedling densities may have been under-estimated in our study, as sampling began in April 2004, 
15 months after the fire. Nevertheless, greater mortality was expected over the following six years, especially given that Callitris seedlings were so much smaller than associated Eucalyptus seedlings. Post-fire rainfall at the nearby Beechworth weather station was slightly higher than the long-term average for the first three years after burning (2003-2005), which would have assisted initial seedling establishment. However, rainfall in subsequent years was relatively low, with just 43% of mean annual rainfall in 2006 (413 mm) and ca. 80% of average from 2007–2009 (755–790 mm; Bureau of Meteorology 2010). 
Callitris species are extremely drought tolerant (Attiwill and Clayton-Greene 1984; Zeppel and Eamus 2008; Brodribb et al. 2010), and saplings self-thin extremely slowly, forming dense ‘locked stands’ containing suppressed, slow-growing trees (Lacey 1973; Thompson and Eldridge 2005; Ross 2008). Lacey (1973) reported that ‘in excess of … 125,000 [trees]/ha are commonly encountered....over widespread areas’ in 20 year old stands of C. glaucophylla. At the 100 m2 plot scale, the maximum density of C. endlicheri seedlings at Mt. Pilot in 2010 was 13 050 seedlings/ha. In unburnt areas at Mt. Pilot, stands suspected to be over 100 years old contain up to 50 live Callitris/100 m2 (5 000 Callitris/ha) and exceed 60 m2/ha basal area (I. Lunt, unpubl. data). Thus, C. endlicheri can persist in dense stands for many decades, similar to C. glaucophylla. This ability to tolerate low resource levels, especially low levels of soil moisture (Brodribb et al. 2010), for lengthy periods, may allow C. endlicheri to persist in mixed forests containing dense Eucalyptus regrowth, provided that plants are not killed by fire or other disturbances.
2.3.4	Seed cone production
Callitris species are killed when subjected to 100% leaf scorch and do not resprout after fire or form a soil seed bank (Bowman et al. 1988b; Hawkins 1966; Stocker 1966; Cohn 
et al. 2011). Consequently, populations are prone to extinction if high intensity fires occur before regenerating plants set seed (Keith 1996). Callitris populations at Mt. Pilot will remain susceptible to fires for many years as only 2% of plants had formed seed cones within seven years of the 2003 fire. A fire-free period of at least 15 years is considered necessary to maintain populations of Callitris species elsewhere (Price and Bowman 1994; Russell-Smith et al. 1998; Bradstock and Cohn 2002).
Our results show that the length of the primary juvenile period (or duration of ‘immaturity risk’) is size dependent, as fast-growing, tall seedlings produced seed cones earlier than smaller, slow-growing seedlings. Moreover, rates of plant growth and seed production were both negatively associated with the density of Eucalyptus seedlings. Callitris seedlings grew faster and produced seed cones earlier in plots with fewer Eucalyptus seedlings, regardless of the density of Callitris seedlings. 
Thinning trails have shown that competition constrains plant growth and levels of seed production in Callitris (Lacey 1972; Knott 1995; Thompson and Eldridge 2005). However, little information is available on the effects of stocking levels on the primary juvenile period, other than the general observation that, ‘suppressed trees exhibit little flowering and therefore have poor seed production’ (Lacey 1972, p. 7), and similar observations (Prober and Thiele 2004). However, competition has been shown to extend the primary juvenile period in other conifers, including Pinus species (Cremer 1992; Verkaik and Espelta 2006). Thus, while removal experiments are required before spatial variations in primary juvenile period can unequivocally be attributed to competition from Eucalyptus seedlings, this interpretation is consistent with prior information (Lacey 1972, 1973; Clayton-Greene 1981; FCNSW 1988), and it appears highly likely that competition contributes at least partly to the observed pattern.
These patterns have implications for future fire management. Under all but extreme conditions, fires are more likely to kill small than large Callitris (Bowman et al. 1988b; Prober and Thiele 2004; Cohn et al. 2011; Zimmer et al. 2011). Consequently, if managers aim to maintain Callitris populations, then fires of moderate to high intensity should be excluded from areas containing young Callitris and moderate to dense Eucalyptus regeneration for longer than areas containing young Callitris amid sparse Eucalyptus regeneration. High basal area of Callitris reduces fire intensity in mixed Eucalyptus–Callitris stands (Bowman and Wilson 1988; Cohn et al. 2011). Consequently, over the longer term, protection of Callitris populations may reduce forest flammability and potential fire intensity.
2.4	Conclusion
These results indicate that Bond’s (1989) model provides a useful framework for interpreting Callitris dynamics in mixed forests co-dominated by Eucalyptus. Australian ecologists have commonly interpreted Callitris dynamics in fire-prone ecosystems in relation to immaturity risk, or the risk of repeated fires occurring before regenerating plants set adequate seed (Bowman et al. 1988b; Russell-Smith et al. 1998; Bradstock and Cohn 2002; Thompson and Eldridge 2005). This attribute is clearly important at Mt. Pilot, as elsewhere. However, Bond’s (1989) model highlights that immaturity risk may be strongly influenced by competition from co-occurring species. By inhibiting plant growth and lengthening the primary juvenile period, competitors may extend the period of immaturity risk, and potentially reduce the habitability of productive environments for Callitris and other non-resprouters. The mechanism of this extended immaturity risk may include an extended opportunity for browsing to eliminate Callitris seedlings and for fires to burn (and hence kill) plants before adequate seed is set. Regardless of the physiological or anatomical mechanisms that control growth rates, the spatial pattern of slower Callitris growth in areas with dense Eucalyptus regeneration has implications for future fire management. To maintain Callitris populations, fire-free intervals should be longer in areas stocked with Callitris, particularly areas in which Callitris is a minor component of the flora and where dense Eucalyptus regeneration dominates the regrowing vegetation.

Section 3 – Summary of Management Implications
The inland-draining slopes and ridges stretching from around Beechworth to Pine Mountain, particularly on soils derived from granite or similar igneous rocks, are the principal Victorian occurrence of forests (co-)dominated by Black Cypress-pine Callitris endlicheri. These forests are a distinctive landscape feature in a region where eucalypts are otherwise the overwhelmingly dominant canopy trees.
Callitris is a widespread genus—the most widespread native conifer in Australia. There are species in woodland near the tip of Cape York and in rocky gullies in Eastern Tasmania. It occurs in arid, semi-arid, mesic, tropical and temperate environments, to high in the (sub-)alps.
In spite of this ecological and geographical spread, Callitris is not commonly the principal tree genus at a site. Part of this ecological restriction may be attributed to its susceptibility to fire. Callitris species are markedly susceptible to fire – individuals of all species can be killed by fire of even moderate intensity, and regeneration is thence solely from seed. No Callitris species consistently resprouts after being burnt.
Nevertheless, some species occupy (moderately) fire-prone habitats by developing serotinous seed (seed which is held in protective woody cones until fire triggers seed release into the immediate post-fire environment). Callitris canescens (in South Australia and west thereof) and Callitris verrucosa (in semi-arid southern Australia) occupy such moderately fire-prone environments and utilize serotiny as a survival strategy. Elsewhere, other species are only weakly to moderately serotinous and retain seed in cones in their canopies for a relatively short period, enabling germination and establishment in unburnt vegetation. Callitris endlicheri (Black Cypress-pine) is in this latter group.
We have previously discussed the obligately slow growth of Callitris seedlings (indeed, obligate slow growth for all conifers) when compared with the high growth rates of eucalypt seedlings. Growth of (post-fire) seedlings is also constrained by competition with coincident eucalypt seedlings and with resprouting eucalypts at the same sites, remembering that resprouting eucalypts are growing on mature, extensively-ramifying root systems.
At the same time, Callitris is often interpreted as being more drought (water stress) resistant than associated eucalypts. Callitris often grow well in topographically arid sites (such as shallow soil profiles over and amongst rocks on ridges and exposed slopes, as at Mt. Pilot) immersed in a matrix of deeper soils where eucalypts dominate. In addition, exposed rocks may help protect Callitris from fires, by breaking fuel continuity, thus providing fire-protected sites. The drought tolerance of Callitris may explain the ability of many Callitris species to germinate and establish in unburnt vegetation from time to time, whereas associated eucalypts are often unable to establish from seed unless the site has been recently burnt.
Finally, Callitris foliage is often not just palatable, but also actively sought by mammalian browsers.
All these ecological features of Callitris and associated eucalypts affect the outcome of competitive interactions between these two forest components, and the interactions between Callitris, eucalypts and the local environment and disturbance regime. These interactions determine the composition of the tree canopy and whether sites support forests dominated by Callitris, by Eucalyptus or by an admixture of both. Keeping these considerations in mind, it is timely to address the questions articulated at the beginning of this report, viz.:
1.	How does the response of C. endlicheri to fire vary with fire frequency?
2.	Is the persistence and recovery of C. endlicheri at a site affected by competition with associated eucalypts? Are mixed stands (Eucalyptus and Callitris) more prone to Callitris extinction or decrease after fires than are pure stands of Callitris?
3.	Are the structure and fire responses of the Flagstaff Range C. endlicheri population (a small mixed stand) comparable with the population structure and post-fire responses of the much larger stands north of Beechworth, around Mt. Pilot? How far can we extrapolate results from study of the Mt. Pilot population?
4.	Does exclusion fencing (or other browsing reduction) increase the likelihood of Callitris seedling survival and growth?
5.	How many years before C. endlicheri produce seed? Is tree size a better indicator of fecundity than tree age?
3.1	How does the response of C. endlicheri to fire vary with fire frequency?
Black Cypress-pines are usually killed by fire. Wildfires are usually higher severity than prescribed burns and usually kill whole stands. Prescribed fires are usually (but not always) of sufficient severity to kill most trees within a stand. Black Cypress-pines regenerate (almost) solely from seed after being burnt and (due to a low growth rate) have an extended juvenile period, in which there is no local seed reserve for regeneration if the site is burnt again. An extended juvenile period heightens the susceptibility of regenerant seedlings to browsing damage (or removal). Two fires in quick succession will cause local extinctions of Black Cypress-pines. Long intervals between fires favour dominance by Black Cypress-pines.
3.2 	Is the persistence and recovery of C. endlicheri at a site affected by competition with associated eucalypts? Are mixed stands (Eucalyptus and Callitris) more prone to Callitris extinction or decrease after fires than are pure stands of Callitris?
After fires, there is competition between cypress-pine seedlings, eucalypt seedlings and resprouting eucalypts in mixed stands. Cypress-pines are drought tolerant and necessarily slow-growing. Competition with resprouting eucalypts further retards growth in cypress-pines, thus increasing the likelihood that a second fire or browsing will remove regenerating cypress-pines. After fires, mixed stands are more prone to local extinction of the cypress-pine component than are pure stands of cypress-pines.
3.3	Are the structure and fire responses of the Flagstaff Range C. endlicheri population (a small mixed stand) comparable with the population structure and post-fire responses of the much larger stands north of Beechworth, around Mt. Pilot? How far can we extrapolate results from study of the Mt. Pilot population?
The Flagstaff Range population exhibited very similar ecological responses to mixed populations around Mt. Pilot. Ecological (and fire) responses were consistent across the species’ local range, and consistent with responses from other non-serotinous Callitris species elsewhere in Australia. It is clear that ecological behaviour and fire responses of the other non-serotinous cypress-pine species in Victoria can be reliably predicted from this and other studies. These other species are: 
•	Slender Cypress-pine Callitris gracilis in the north-west and far west
•	Oyster Bay Cypress-pine Callitris rhomboidea in the Grampians, the Gippsland coast and western heathlands
•	White Cypress-pine Callitris glaucophylla scattered throughout the State.
However, at the same time, the different ecological behaviour deriving from different local populations of browsers must also be taken into account in other sites and with these other species.
Furthermore, we can now reliably predict the long-term implications of changes in fire regimes for Black Cypress-pine Callitris endlicheri (and, by extension) other cypress-pines which occur immersed amongst eucalypts, including both bushfires and prescribed fires.
3.4	Does exclusion fencing (or other browsing reduction) increase the likelihood of Callitris seedling survival and growth?
Exclusion fencing and other browsing reduction may or may not, increase the survival chances of cypress-pine seedlings, whether in burnt or unburnt stands. In situations with high populations of browsers (such as rabbits, goats or macropods) exclusion fencing and targeted browser reduction will substantially increase cypress-pine seedling survival and enable establishment of new individuals. Where these browsers are less common, cypress-pine survival and establishment is less affected by browsing pressure. In the absence of fire, browsing pressure is the most important determinant of cypress-pine recruitment.
This conclusion is also directly applicable to (all) other cypress-pine species, including the serotinous Scrub Cypress-pine Callitris verrucosa.
3.5	How many years before C. endlicheri produce seed? Is tree size a better indicator of fecundity than tree age?
The number of years it takes Black Cypress-pines to mature depends on local growth rates. Rapidly growing trees may mature (start producing viable seed) in seven years, but only a very small proportion (~2%) of the population reaches maturity at this early age. Other plants, particularly in other, less favourable situations, will take at least 15 or more years to start producing seed. The time taken to recruit an adequate seed bank for replacement of the parent population is considerably longer (particularly for serotinous species). Minimum tolerable fire intervals vary with local (site) conditions.
There is a direct and strong relationship between plant size and primary juvenile period (time taken to produce viable seed) in Black Cypress-pines (and, by extension, in other cypress-pines as well). Larger plants set viable seed decidedly sooner than smaller plants, even when of the same age. Size is a better indicator of fecundity than tree age. The best indicator of fecundity is the number of mature cones present on trees.
3.6	Concluding remarks
This study has collected data that enable managers (and other ecologists) to predict cypress-pine responses to individual bushfires and to burning regimes that include the application of prescribed fires. Managers may now derive and apply ecologically appropriate fire regimes that can assist local survival of cypress-pines.

References 
Adams R. (1999) Germination of Callitris seeds in relation to temperature, water stress, priming, and hydration-dehydration cycles. Journal of Arid Environments 43, 437–448.
Allcock K. G., Hik D. S. (2004) Survival, growth, and escape from herbivory are determined by habitat and herbivore species for three Australian woodland plants. Oecologia 138(2), 231–241.
Andersen A. N. (1988) Immediate and longer-term effects of fire on seed predation by ants in sclerophyllous vegetation in south-eastern Australia. Australian Journal of Ecology 13, 285–293.
Attiwill P. M., Clayton-Greene K. A. (1984) Studies of Gas Exchange and Development in a Subhumid Woodland. Journal of Ecology 72, 285–294.
Austin M. P. and Williams O. B. (1998) Influence of climate and community composition on the population demography of pasture species in semi-arid Australia. Vegetatio 77, 43–49.
Baker P. J., Palmer J. G. and D’Arrigo R. (2008) The dendrochronology of Callitris intratropica in northern Australia: annual ring structure, chronology development and climate correlations. Australian Journal of Botany 56(4): 311–320.
Becker P. (2000) Competition in the regeneration niche between conifers and angiosperms: Bond’s slow seedling hypothesis. Functional Ecology 14(4), 401–412.
Becker P., Tyree M. T., Tsuda M (1999) Hydraulic conductances of angiosperms versus conifers: Similar transport sufficiency at the whole-plant level. Tree Physiology 19(7), 445–452. 
Bond W. J., Scott A. C. (2010) Fire and the spread of flowering plants in the Cretaceous. New Phytologist 188(4), 1137–1150. 
Bond W. J. (1989) The tortoise and the hare: ecology of angiosperm dominance and gymnosperm persistence. Biological Journal of the Linnean Society 36(3), 227–249. 
Bonnet V. H., Schoettle A. W. and Shepperd W. D. (2005) Postfire environmental conditions influence the spatial pattern of regeneration for Pinus ponderosa. Canadian Journal of Forest Research 35, 37–47.
Bowman D. M. J. S., Price O, Whitehead P. J. and Walsh A. (2001) The ‘wilderness effect’ and the decline of Callitris intratropica on the Arnhem Land Plateau, northern Australia. Australian Journal of Botany, 49, 665–672
Bowman D. M. J. S. and Harris S. (1995) Conifers of Australia’s Dry Forests and Open Woodlands. pp. 2520270 in Ecology of the Southern Conifers Enright NJ and Hill RS (eds.), Melbourne University Press, Melbourne, Australia.
Bowman D. M. J. S. and Latz P. K. (1993) Ecology of Callitris glaucophylla (Cupressaceae) on the MacDonnell Ranges, Central Australia. Australian Journal of Botany 41, 217–25.
Bowman D. M. J. S., Panton W. J. (1993) Decline of Callitris intratropica R.T. Baker & H.G. Smith in the Northern Territory: implications for pre- and post-European colonization fire regimes. Journal of Biogeography 20, 373–381. 
Bowman D. M. J. S., Wilson B.A., Davis G.W. (1988a) Response of Callitris intratropica R.T. Baker & H.G. Smith to fire protection, Murgenella, northern Australia. Australian Journal of Ecology 13, 147–159. 
Bowman D. M. J. S., Wilson B. A. (1988b) Fuel characteristics of coastal monsoon forests, Northern Territory, Australia. Journal of Biogeography 15, 807–817. 
Bradstock R. A., Bedward M., Cohn J. S. (2006) The modelled effects of differing fire management strategies on the conifer Callitris verrucosa within semi-arid mallee vegetation in Australia. Journal of Applied Ecology 43(2), 281–292. 
Bradstock R. A., Cohn J. S. (2002) Demographic characteristics of mallee pine (Callitris verrucosa) in fire-prone mallee communities of central New South Wales. Australian Journal of Botany 50(5), 653–665. 
Briggs S. V., Taws N. M., Seddon J. A. and Vanzella B. (2008) Condition of fenced and unfenced remnant vegetation in inland catchments in south-eastern Australia. Australian Journal of Botany 56(7), 590–599.
Brodribb T. J., Holbrook N.M., Hill R.S. (2005) Seedling growth in conifers and angiosperms: impacts of contrasting xylem structure. Australian Journal of Botany 53, 749–755.
Brodribb T. J., Bowman D., Nichols S., Delzon S., Burlett R. (2010) Xylem function and growth rate interact to determine recovery rates after exposure to extreme water deficit. New Phytologist 188(2), 533–542. 
Bureau of Meteorology (2010) Weather station data 
for Beechworth [82001]. Available online 
http://www.bom.gov.au/climate/data/weather-data.shtml. Accessed March 2011. 
Callister K. E. (2004) Casuarina pauper (Belah) Woodlands of Northwest Victoria: Monitoring and RegenerationCentre for Environmental Management. University of Ballarat, Ballarat, Victoria.
Carey A., Evans M., Hann P., Lintermans M., MacDonald T., Ormay P., Sharp S., Shorthouse D. and Webb N. (2003) Wildfires in the ACT 2003: Report on initial impacts on natural ecosystems. Environment ACT, Canberra.
Cheal D. C. (2005) Goat Damage in Mallee in Murray-Sunset National Park. Victorian Naturalist 122, 108–112.
Clayton-Greene K. A. (1981) The autecology of Callitris columellaris F. Muell. and associated Eucalyptus spp. in south-eastern Australia. Ph.D. thesis, University of Melbourne, Melbourne.
Clayton-Greene K. A., Ashton D. H. (1990) The dynamics of Callitris columellaris/Eucalyptus albens communities along the Snowy River and its tributaries in south-eastern Australia. Australian Journal of Botany 38, 403–432. 
Cochrane G. R. and McDonald N. H. E. (1966) A Regeneration Study in the Victorian Mallee. Victorian Naturalist 83, 220–226.
Cohn J. S., Lunt I. D., Ross K. A., Bradstock R. A. (2011) How do slow-growing, fire-sensitive conifers survive in flammable eucalypt woodlands? Journal of Vegetation Science 22, 425–435. 
Cornelissen J. H. C., Diez P. C., Hunt R. (1996) Seedling growth, allocation and leaf attributes in a wide range of woody plant species and types. Journal of Ecology 84, 755–765.
Cremer K. W. (1992) Relations between reproductive growth and vegetative growth of Pinus radiata. Forest Ecology and Management 52, 179–199. 
DeBano L. F., Neary D. G. and Folliott P. F. (1998) Fire’s Effects on Ecosystems. John Wiley and Sons, New York, USA.
Elsey C. W. (1957) The establishment of stands of Callitris in the Warby Ranges. Dip. For. Thesis, University of Melbourne. cited in Clayton-Green and Ashton (1990).
Ferran A. and Vallejo V. R. (1992) Litter dynamics in post-fire successional forests of Quercus ilex. Vegetatio 99–100, 239–246.
Florence R. G. (1996) ‘Ecology and silviculture of eucalypt forests.’ (CSIRO: Collingwood, Victoria) 
Forestry Commission of New South Wales (FCNSW) (1988) Notes on the silviculture of major N.S.W. forest types. 10. Cypress pine types. Forestry Commission of New South Wales, Sydney, NSW.
Gill A. M. and McCarthy M. A. (1998) Intervals between prescribed fires in Australia: what intrinsic variation should apply? Biological Conservation 85(1–2), 161–169.
Grime J. P. (2001) ‘Plant strategies, vegetation processes, and ecosystem properties.’ (John Wiley & Sons: Chichester) 
Harris M. (2002) Cypress Pine Forests. Australian Plants 21(171), 317–319.
Harris M. A., Lamb D. and Erskine P. D. (2003) An investigation into the possible inhibitory effects of white cypress pine (Callitris glaucophylla) litter on the germination and growth of associated ground cover species. Australian Journal of Botany 51(1), 93–102.
Hawkins P. J. (1966) Seed production and litter fall studies of Callitris columellaris. Australian Forest Research 2(2), 3–16. 
Keith D. (1996) Fire-driven extinction of plant populations: a synthesis of theory and review of evidence from Australian vegetation. Proceedings of the Linnean Society of New South Wales 116, 37–78. 
Knott J. (1995) White cypress pine thinning trials of the Western Region. Research Paper No. 27, State Forests of New South Wales, Australia.
Knox K. J. E. and Clarke P. J. (2006) Fire season and intensity affect shrub recruitment in temperate sclerophyllous woodlands. Oecologia 149(4), 730–739.
Lacey C. J. (1972) Factors influencing occurrence of cypress pine regeneration in New South Wales. Technical Report No. 21, Forestry Commission of NSW, Australia.
Lacey C. J. (1973) Silvicultural characteristics of white cypress pine. Research Note No. 26, Forestry Commission of NSW, Australia.
Leigh J. H., Wood D. H., Holgate A. and Stanger M. G. (1989) Effects of rabbit and kangaroo grazing on two semi-arid grassland communities in central-western New South Wales. Australian Journal of Botany 37, 375–396.
Lindsay A. D. (1967) Forest types of the New South Wales cypress pine zone. Forestry Commission of N.S.W. Technical Paper No. 8. cited in Clayton-Green and Ashton (1990).
Lusk C. H., Wright I., Reich P. B. (2003) Photosynthetic differences contribute to competitive advantage of evergreen angiosperm trees over evergreen conifers in productive habitats. New Phytologist 160(2), 329–336. 
Mackenzie B. D. E., Keith D. A. (2009) Adaptive management in practice: conservation of a threatened plant population. Ecological Management & Restoration 10, S129–S135. 
Murdoch F. (2006). Vegetation Change in Hattah Kulkyne National Park: A State-and-transition Model. Proceedings of the Royal Society of Victoria 118(2), 305–312.
Myster R. W. and Pickett S. T. A. (1993) Effects of litter, distance, density and vegetation patch type on postdispersal tree seed predation in old fields. Oikos 66,381–388
Parks Victoria (2008) ‘Chiltern-Mt. Pilot National Park management plan.’ (Parks Victoria: Melbourne) 
Pearson S. G. and Searson M. J. (2002). High-resolution data from Australian trees. Australian Journal of Botany 50(4), 431–439.
Price O., Bowman D. M. J. S. (1994) Fire-stick forestry: a matrix model in support of skilful fire management of Callitris intratropica R. T. Baker by north Australian aborigines. Journal of Biogeography 21, 573–580.
Prior L. D., Lee Z., Brock C., Williamson G. J., Bowman D. M. J. S. (2010) What limits the distribution and abundance of the native conifer Callitris glaucophylla (Cupressaceae) in the West MacDonnell Ranges, central Australia? Australian Journal of Botany 58(7), 554–564. 
Prober S. M., Thiele K. R. (2004) Fire recovery vegetation monitoring in White Box – White Cypress Pine woodlands of East Gippsland. Technical Report, Department of Sustainability and Environment, Victoria, Australia.
Read J. (1995) Recruitment characteristics of White Cypress Pine (Callitris glaucophylla) in arid South Australia. Rangeland Journal 17, 228–240. 
Reich P. B., Ellsworth D. S., Walters M. B., Vose J. M., Gresham C., Volin J. C., Bowman W. D. (1999) Generality of leaf trait relationships: A test across six biomes. Ecology 80(6), 1955–1969. 
Rice S. K. (1993) Vegetation establishment in post-fire Adenostoma chapparal in relation to fine-scale pattern in fire intensity and soil nutrients. Journal of Vegetation Science 4, 115–124.
Ross K. A., Bedward M., Ellis M. V., Deane A., Simpson C. C., Bradstock R. A. (2008) Modelling the dynamics of white cypress pine Callitris glaucophylla woodlands in inland south-eastern Australia. Ecological Modelling 211, 11–24.
Russell-Smith J. (2006) Recruitment dynamics of the long-lived obligate seeders Callitris intratropica (Cupressaceae) and Petraeomyrtus punicea (Myrtaceae). Australian Journal of Botany 54(5), 479–485.
Russell-Smith J., Ryan P. G., Klessa D., Waight G., Harwood R. (1998) Fire regimes, fire-sensitive vegetation, and fire management of the sandstone Arnhem Plateau, monsoonal northern Australia Journal of Applied Ecology 35, 829–846.
Sandell P. (2003) The Implications of RHDV for Biodiversity in North-west Victoria Hattah RHD Project. Parks Victoria and Department of Sustainability & Environment, Melbourne, Victoria, Australia.
Sandell P. M., Ballentine M. and Horner G. (2002) Vegetation Recovery in the Victorian Mallee Parks 1991–1998. Parks Victoria, Melbourne, Victoria, Australia.
Scott J. A. (1992) The natural vegetation of the Balranald – Swan Hill area. Cunninghamia 2(4), 597–652.
Stocker G. C. (1966) ‘Aspects of the seeding habit of Callitris intratropica.’ (Department of National Development: Canberra) 
Stokes, M.A. and Smiley, T.L. (1968) An Introduction to Tree Ring Dating. University of Chicago, Chicago.
Thompson W. A., Eldridge D. J. (2005) White cypress pine (Callitris glaucophylla): a review of its roles in landscape and ecological processes in eastern Australia. Australian Journal of Botany 53(6), 555–570.
Walker P. J. and Green D. R. (1979) A note on the effects of wildfire on trees and shrubs in the Cobar District , New South Wales. Journal of the Soil Conservation Service of New South Wales 35(3), 126–132.
Wondzell S. M. and King J. G. (2003) Postfire erosional processes in the Pacific Northwest and Rocky Mountain regions. Forest Ecology and Management 178, 75–87.
Verkaik I, Espelta J. M. (2006) Post-fire regeneration thinning, cone production, serotiny and regeneration age in Pinus halepensis. Forest Ecology and Management 231(1–3), 155–163. 
Watson C. (2004) ‘Habitat modelling and effects of fire on Callitris endlicheri in the Chiltern-Mt. Pilot National Park, Victoria.’ (School of Environmental and Information Sciences, Charles Sturt University: Albury) 
Wright I. J., Reich P. B., et al. (2004) The worldwide leaf economics spectrum. Nature 428(6985), 821–827. 
Zeppel M., Eamus D. (2008) Coordination of leaf area, sapwood area and canopy conductance leads to species convergence of tree water use in a remnant evergreen woodland. Australian Journal of Botany 56(2), 97–108.
Zimmer H., Green P., Cheal D., Clarke M. F. (2011) Reconstructing Mallee fire history using Callitris verrucosa tree rings. Technical Report no. 215, Arthur Rylah Institute for Environmental Research, Heidelberg, Victoria, Australia.
Zimmer W. S. (1944) Notes on the regeneration of Murray Pine (Callitris spp.). Transactions of the Royal Society of South Australia 68, 183–90.