Arthur Rylah Institute for Environmental Research
Technical Report Series No. 153
Recovery of Mountain Plum-Pine
Shrubland After Wildfire (Cobberas)
Arn Tolsma, Fiona Coates & Geoff Sutter
December 2004
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Technical Report No. 153
Mountain Plum-pine Recovery
Published by the Victorian Government Department of Sustainability and Environment
Melbourne, December 2004
© The State of Victoria Department of Sustainability and Environment 2004
This publication is copyright. No part may be reproduced by any process except in
accordance with the provisions of the Copyright Act 1968.
ISBN 1 74152 086 X
ISSN 0810-5774
For more information contact the DSE Customer Service Centre 136 186
Front cover: Mountain Plum-Pine (Podocarpus lawrencei) on Cleft Peak, eastern Victoria.
Disclaimer
This publication may be of assistance to you but the State of Victoria and its employees do
not guarantee that the publication is without flaw of any kind or is wholly appropriate for
your particular purposes and therefore disclaims all liability for any error, loss or other
consequence which may arise from you relying on any information in this publication.
Citation
Tolsma, A, Coates, F. and Sutter, G. (2004) Recovery of Mountain Plum-Pine Shrubland After
Wildfire (Cobberas). Arthur Rylah Institute for Environmental Research Technical Report
Series No. 153. Department of Sustainability and Environment, Victoria, Melbourne.
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Mountain Plum-pine Recovery
Contents
Contents ........................................................................................................................ III
List of Figures and Tables ............................................................................................... IV
Executive Summary .......................................................................................................... V
Introduction ..................................................................................................................... 6
Methods ............................................................................................................................ 9
Results and Discussion ................................................................................................... 11
Management Implications .............................................................................................. 20
Acknowledgments .......................................................................................................... 23
References ...................................................................................................................... 24
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List of Figures and Tables
Figures
Figure 1. Mountain Plum-Pine (Podocarpus lawrencei). . .................................................................. 6
Figure 2. Distribution of Podocarpus lawrencei in Victoria ............................................................. 7
Figure 4. Podocarpus population ‘PLAW3’ at Cleft Peak. This population was mostly
unburnt, with only minor scorching at the edges. .................................................................... 13
Figure 5. Podocarpus population ‘PLAW7’ at Cobberas 1. Only around 10% of this
population remained unburnt, with 80% currently showing no signs of regeneration. ... 14
Figure 6. Podocarpus population ‘PLAW11’ at Middle Peak. This population was only burnt
in one small corner. ......................................................................................................................... 15
Figure 8. Burnt Podocarpus at the edge of a community at Moscow Peak. Fire intensity was
almost always higher at the margins than within the community. ....................................... 17
Figure 9. Dead Podocarpus in the centre of a community at Middle Peak, with fire intensity
only sufficient to burn the bark. ................................................................................................... 18
Figure 10. Resprouting from epicormic buds on lower branches at Cleft Peak. ....................... 18
Figure 11. Resprouting from epicormic buds on a lightly scorched, small specimen of
Podocarpus at Cleft Peak. ................................................................................................................ 19
Figure 12. Three year-old resprouts on a Podocarpus that was burnt at Cleft Peak in April
2001, highlighting the low growth rate. ...................................................................................... 19
Figure 13. Podocarpus seedlings under scorched shrubs at Moscow Peak ................................ 20
Figure 14. Podocarpus seedling at Moscow Peak. Root resprouts were outwardly similar, but
lacked the soft, white root tissue. ................................................................................................. 20
Figure 15. Hoof damage from horses among rocky outcrops at Moscow Peak. ....................... 21
Tables
Table 1. Summary data for 25 populations of Podocarpus lawrencei in the Cobberas area,
eastern Victoria. . ............................................................................................................................. 11
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Mountain Plum-pine Recovery
Executive Summary
Populations of Mountain Plum-Pine (Podocarpus lawrencei), ranging in size from around
10 m2 to 3000 m2, were assessed at five peaks on the Cobberas Range, eastern Victoria in
March 2004 under the Victorian Bushfire Recovery Program. The aims were to determine the
extent of damage to the populations from the 2003 alpine fires, the mode and success of
regeneration, any threats that might act upon that regeneration, and to identify urgent
management actions.
The proportion of each population killed varied substantially, ranging from zero to 95%.
The total proportion killed at each of the five peaks ranged from 2% to 63%, with an overall
average of 28%. Podocarpus did not carry fire with the same intensity as adjacent shrubby
vegetation, but it was sufficiently sensitive to fire that burning of the bark at the base of the
trunk caused plant death.
Regeneration of scorched plants was occurring, albeit at low levels, through resprouts on the
trunks and branches, and occasional root resprouts. Sprout location was directly related to
the intensity with which individual plants were burnt or scorched. Small numbers of
seedlings were present, ranging in size from around 2 to 6 cm.
Fire management plans to protect the remaining populations are recommended, along with
continued rabbit control. Weeds do not currently pose a threat. However, periodical
monitoring of weeds and other factors that might affect on-going regeneration success is
recommended.
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Mountain Plum-pine Recovery
Introduction
The Mountain Plum-Pine Podocarpus lawrencei (Figure 1) is the only native conifer occurring
in the wet forests and alpine areas of mainland eastern Australia (Gibson et al. 1995).
Figure 1. Mountain Plum-Pine (Podocarpus lawrencei). Clockwise (from top left); growth
habit, female seed, male cones, male cones on branch, leaves. Source: Viridans Biological
Databases and Andy Blackburn.
This small-leaved conifer, with separate male and female plants, is widespread as a small to
medium shrub of rocky areas in alpine and sub-alpine areas of Victoria (Figure 2), Tasmania
and New South Wales. In exposed areas the species is often procumbent, hugging the face of
glacial moraines, rock screes and outcrops. Where larger rocks afford adequate protection it
may occur as a spreading shrub up to 2 metres tall.
Very occasionally the species (or plants with close affinities) is found as a large shrub or
small tree (up to 20 metres tall) in subalpine woodland (such as at Echo Flat, Lake Mountain)
or in montane wet forest (Goonmirk Rocks on the Errinundra Plateau (Podocarpus spp. aff.
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nov.) and a site on the Mersey River in Tasmania). These non-alpine occurrences have
generated much interest as to the age of the plants and their taxonomic, genetic and
ecological significance. The likely fire history of such sites is of particular interest, as the
species is usually considered to be both slow growing and sensitive to all but the lowest
intensity fires (Barker 1991). Indeed, growth rates are so slow that a 170-year old specimen
near Mt Kosciuszko was recorded with a trunk diameter of only 6 cm (ANBG 2003).
Figure 2. Distribution of Podocarpus lawrencei in Victoria (Source: Viridans Biological
Databases).
Alpine vegetation communities dominated by Podocarpus lawrencei are thought to be
pioneers of scree slopes (Costin et al. 1979) and the protection provided by the shrub may
be important in the colonisation of this habitat by many plants and animals. Most notably,
the endangered Mountain Pygmy-Possum (Burramys parvus) relies heavily on this habitat for
shelter and food. Due to its restricted range and importance, Mountain Plum-Pine Shrubland
is potentially a threatened community in Victoria.
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Mountain Plum-pine Recovery
The extensive fires in eastern Victoria and southern New South Wales of January-February
2003 burnt a large part of the Mountain Plum-Pine’s mainland range, raising concerns about
the species survival and regeneration over large areas. The ability of the community to
recover from fire is relatively unknown, although seedlings and basal resprouts were
observed after a fire on the Cobberas Range in April 2001 (Edwards 2003).
This project was identified in the Statewide Public Land Ecological and Cultural Fire
Recovery Plan (Parks Victoria and Department of Sustainability and Environment 2003). The
objectives of the project were:

Identify threats currently and potentially acting on the community in the Alpine National
Park along the Cobberas Range,

Identify urgent management requirements

Provide baseline information to monitor progress of key species or communities toward
recovery.
In particular, threats related to the grazing and browsing by both native and pest animal
populations were to be considered when identifying management recommendations.
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Mountain Plum-pine Recovery
Methods
The peaks commonly referred to as the Cobberas Range are situated in the far east of
Victoria, close to the headwaters of the Murray River (Figure 3), and range in altitude from
1640 m to 1830 m. The geology consists mostly of igneous extrusive rocks dating from the
Lower Devonian, such as rhyodacite, andesite, basalt and rhyolite (LCC 1977). The region
has mean annual precipitation of around 1600 mm (much of it as snow), and mean minimum
to maximum daily temperatures of around 1º to 11º in winter, and 9º to 26º in summer
(Australian Bureau of Meteorology).
Field assessments of the Mountain Plum-Pine Podocarpus lawrencei populations on five
peaks of the Cobberas area were undertaken from 20 to 24 March 2004:

Cleft Peak (1760 m)

Middle Peak (1760 m)

Cobberas No. 1 (1830 m)

Cobberas No. 2 (1720 m)

Moscow Peak (1640 m)
All populations assessed were recorded on sketch maps and the approximate boundaries of
the population recorded using a handheld GPS unit. The following data were recorded for
each population:

Proportion of Podocarpus plants ‘killed’ by recent fire (not presently showing
signs of regeneration)

Proportion of Podocarpus plants scorched but not killed by the fire

Proportion of Podocarpus plants unburnt

Presence of resprouting from the base or branches of scorched shrubs

Presence of Podocarpus seedlings
It was initially anticipated that individual resprouting plants and seedlings would be
recorded for future monitoring. However, the large number of resprouts and very small
numbers of seedlings were deemed to make monitoring impractical given the time and
budget of this and likely future projects.
In addition to ground based monitoring, oblique aerial photographs were taken of selected
populations. These were not utilised for the current report, but might be able to assist
future monitoring or mapping. The approximate location of each photograph was recorded
using a GPS unit.
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Mountain Plum-pine Recovery
2 km
Figure 3. Cobberas Ranges showing locations of areas searched and populations assessed.
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Mountain Plum-pine Recovery
Results and Discussion
Approximately 30 - 40 Podocarpus lawrencei populations were located in the Cobberas area,
ranging in size from as little as 1 m2 to around 3000 m2. The largest individual populations
were located on Cleft Peak, with high cover noted within the cleft and on the southern
flanks. The great majority of plants were located on rocky slopes or outcrops of a southerly
(south-west to south-east) aspect. There were few populations with a more northerly aspect,
the exception being a minor occurrence at Cleft Peak.
The locations and spatial extent of all populations were recorded (Table 1), with the
exception of some on Cobberas 2, where numerous small populations were widely scattered
over inaccessible terrain. The assessment at this site was somewhat restricted but was
nevertheless sufficient to capture most of the area covered by the species.
Table 1. Summary data for 25 populations of Podocarpus lawrencei in the Cobberas area,
eastern Victoria. Note that blank values for the presence of seedlings or resprouts do not
indicate definitively that they were absent, as it was often not possible to closely examine
sites on rocky outcrops or readily access the centre of large burnt patches.
Site name Location
Area (m2)
% Unburnt
% Scorched % Killed
PLAW01
Cleft Peak
400
0
5
95
PLAW02
Cleft Peak
100
0
80
20
PLAW03
Cleft Peak
900
90
10
0
PLAW04
Cleft Peak
350
90
5
5
PLAW05
Cleft Peak
3000
50
30
20
PLAW16
Cleft Peak
500
95
5
0
59
22
19
Cleft Peak Average
Seedlings
Resprouts
none
minor
some
PLAW06
Cobberas 1
30
95
0
5
PLAW07
Cobberas 1
500
10
10
80
some
PLAW08
Cobberas 1
130
70
15
15
9
PLAW09
Cobberas 1
60
95
3
2
PLAW10
Cobberas 1
50
100
0
0
36
9
55
100
0
0
Cobberas 1 Average
PLAW20
Cobberas 2
10
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PLAW21
Cobberas 2
10
80
20
0
PLAW22
Cobberas 2
300
70
20
10
PLAW23
Cobberas 2
500
95
5
0
PLAW24
Cobberas 2
1500
90
10
0
PLAW25
Cobberas 2
500
90
5
5
89
9
2
Cobberas 2 Average
some
some
PLAW11
Middle Peak
750
95
3
2
PLAW12
Middle Peak
100
80
10
10
some
PLAW13
Middle Peak
1500
0
5
95
minor
PLAW14
Middle Peak
370
0
30
70
PLAW15
Middle Peak
80
0
30
70
28
9
63
Middle Peak Average
many
minor
PLAW17
Moscow Peak
200
60
20
20
36
some
PLAW18
Moscow Peak
30
50
25
25
20
none
PLAW19
Moscow Peak
30
75
25
0
Moscow Peak Average
Total Average
61
21
57
18
15
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The data showed substantial variation in the extent to which populations were affected by
the fire (Figures 4 – 7):

Proportion unburnt ranged from 0 to 100%

Proportion scorched but not killed ranged from 0 to 80%

Proportion killed ranged from 0 to 95%.
On average, around 57% of the Podocarpus dominated communities (by total area) remained
unburnt, 15% was scorched but not killed, and 28% showed no signs of regeneration.
However, analysis of data for the five separate areas showed that Cobberas 1 and Middle
Peak had suffered proportionately greater damage as a result of the fires, with 55% and 63%
respectively of the Podocarpus areas assessed having been killed. In contrast, Cobberas 2,
Moscow Peak and Cleft Peak populations suffered mortality of 2%, 18% and 19% respectively.
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Note that assessment of the damage from the 2003 fires was confounded by the effects of a
fire in April 2001, which partially burnt some communities on Cleft Peak and Middle Peak
(Edwards 2003). It was not always possible to determine which fire had been responsible for
killing parts of particular communities, and some percentages quoted for area killed may
thus overstate the damage from the 2003 fires.
Figure 4. Podocarpus population ‘PLAW3’ at Cleft Peak. This population was mostly
unburnt, with only minor scorching at the edges.
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Figure 5. Podocarpus population ‘PLAW7’ at Cobberas 1. Only around 10% of this
population remained unburnt, with 80% currently showing no signs of regeneration.
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Figure 6. Podocarpus population ‘PLAW11’ at Middle Peak. This population was only burnt
in one small corner.
Figure 7. Podocarpus population ‘PLAW13’ at Middle Peak. This large population was
extensively burnt, with around 95% currently showing no signs of regeneration.
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As well as varying in extent, the fire also varied markedly in intensity from one location to
another, and between vegetation types.
Individual Podocarpus plants were sometimes completely burnt at ground level where they
occurred at the margins of a patch (Figure 8), but were rarely severely burnt within a patch,
even where the burnt area was substantial and many plants were killed (Figure 9). This
suggested that Podocarpus patches were not carrying fire with the same intensity as the
vegetation around it, such as the often severely burnt adjacent patches of Tasmannia
xerophila. However, it also suggested that even low intensity fires merely sufficient to burn
the bark at the base of the trunk could kill Podocarpus.
Where the fire had been less intense, many individual plants were resprouting from buds
under the bark, and these were variously observed on the lower trunk, larger branches
(Figure 10), or even smaller branches (Figure 11). Resprout location was directly associated
with fire intensity, and only plants that were lightly scorched were able to regenerate from
buds on smaller branches. No resprouting shrubs were observed when the bark had been
burnt at the base of the trunk.
Some older resprouting was noted at Cleft and Middle Peaks, where portions of some
communities had been burnt in the fire of April 2001. The size of the 3-year-old resprouts
in Figure 12 demonstrates just how slowly Podocarpus lawrencei grows in this environment.
Seedlings ranging in height from around 2 to 6 cm were noted (Figures 13 & 14), but the
quantity and spatial distribution varied substantially between sites. Many small sites on
rocky outcrops were difficult to examine closely, and the time available precluded closer
examination of the centres of many larger patches. The work was also hampered by the
difficulty in negotiating through such badly burnt communities.
Some populations appeared to entirely lack seedlings. It is not clear whether this is due to a
naturally small seedbank in the soil and leaf litter, or to a limited amount of fruiting and
seed dispersal by birds since the fire. Birds are considered to be the main agent of dispersal
in Podocarpus lawrencei (Bowman & Harris 1995) and, as leaf litter and thin soil still exist
under and around burnt plants, or in gaps between boulders, seedling recruitment is likely
to continue slowly over time.
One individual at Middle Peak was observed resprouting from the roots of an adult plant.
However, it was not possible to routinely distinguish root resprouts from seedlings without
causing unneccesary disturbance to the limited number of individuals present. An unknown
proportion of the individuals classified as seedlings in this report might therefore be
resprouting from root buds.
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Figure 8. Burnt Podocarpus at the edge of a community at Moscow Peak. Fire intensity was
almost always higher at the margins than within the community.
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Mountain Plum-pine Recovery
Figure 9. Dead Podocarpus in the centre of a community at Middle Peak, with fire intensity
only sufficient to burn the bark. The trunk diameter of this plant was around 30 cm.
Figure 10. Resprouting from epicormic buds on lower branches at Cleft Peak.
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Figure 11. Resprouting from epicormic buds on a lightly scorched, small specimen of
Podocarpus at Cleft Peak.
Figure 12. Three year-old resprouts on a Podocarpus that was burnt at Cleft Peak in April
2001, highlighting the low growth rate.
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Mountain Plum-pine Recovery
Figure 13. Podocarpus seedlings under scorched shrubs at Moscow Peak
.
Figure 14. Podocarpus seedling at Moscow Peak. Root resprouts were outwardly similar, but
lacked the soft, white root tissue.
Management Implications
Fire protection
Podocarpus lawrencei, as with other Australian heathy conifers, does not require the
intervention of fire to persist across its range (Kirkpatrick 1983), although it can respond to
disturbance and has a long recruitment phase (Barker 1991). Indeed, some fire protection is
afforded by its rocky habitat, which does not appear to carry as intense a fire as adjacent
shrub communities such as those dominated by Tasmannia xerophila. Fires (or at least high
intensity fires) that could severely affect Podocarpus communities are likely to have been
historically rare. A patch of vegetation at Cleft Peak appeared to be regenerating from a fire
that occurred perhaps 40-50 years ago, but the presence of individual plants with trunk
diameters up to around 30 cm at Middle Peak suggests that some populations have not
experienced fire for hundreds of years.
Nonetheless, some 3300 m2 of Podocarpus community was killed across the five main peaks
during the 2003 fires, including some large, old plants that will take many decades to
20
replace. A subsequent fire would severely impact on the recovery of these populations. This
could be by a reduction in the local seed source that is crucial for dispersal and recruitment,
or by the killing of resprouts on scorched plants before those plants have recovered their
energy reserves in the form of photosynthates.
A Fire Protection Plan that aims to prevent fire from reaching the remaining communities
and ensures that the remaining Podocarpus populations are protected in the foreseeable
future is therefore a crucial part of any management strategy for the Cobberas region.
Grazing
Feral horses are present in the area around the Cobberas, and signs of hoof damage were
seen in some surprisingly steep and rocky areas (Figure 15). No evidence of damage by
horses or other livestock was noted in the Podocarpus dominated communities and
regeneration may not be affected. Nonetheless, this should be monitored.
Figure 15. Hoof damage from horses among rocky outcrops at Moscow Peak.
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Rabbits were seen in the study area particularly around Cobberas 1, and pose a direct threat
to regeneration. Rabbits shelter in the thickets, and browse on seedlings or resprouts with
their higher nutrient content. Given the slow growth rates of seedlings and resprouts, and a
prolonged recruitment and regeneration phase, long-term rabbit control is necessary. Some
rabbit control measures have already been implemented (P. Rennick, PV pers. comm.), but
further control and on-going monitoring should be maintained.
Weeds
The crowded growth structure of Podocarpus heath provides little scope for other species to
live beneath mature foliage, ensuring that it forms a virtual monoculture. No weeds were
noted within the Podocarpus communities, but weeds observed in grassy areas away from
the outcrops included Clover (Trifolium spp.), Sheep Sorrel (Acetosella vulgaris) and Cat’s Ear
(Hypochoeris radicata). Weeds such as Plum (Prunus spp.), Shasta Daisy (Leucanthemum
maximum) and Columbine (Aquilegia vulgaris), which are considered to be possible threats
in other high-altitude heathland areas, were not found.
Weed establishment and persistence would depend heavily on both the availability of
propagules and the on-going regeneration success of the Podocarpus shrubs, but at this
stage weeds are not considered to represent a threat. In any event, active weed control of
highly scattered populations in this remote location would be logistically difficult.
Nonetheless, periodical monitoring is needed to detect any unforeseen outbreak and thus
allow early intervention.
Future monitoring
The remote location of the Cobberas and difficulties in accessing the sites make regular
monitoring of individual plant recovery (via seedlings or resprouts) impractical. However,
some long-term monitoring of overall community response and regeneration success should
be planned, to determine whether any factors are affecting that regeneration. Of most
concern are:



sequential fires that can kill regeneration or limit dispersal of seeds
rabbits or other herbivores targetting the fresh regrowth or seedlings
outbreaks of weeds, particularly competitive woody species
Monitoring, and prompt remedial action if necessary, will ensure that this limited and
important vegetation type can recover and persist in the future.
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Acknowledgments
The authors are grateful to Jenny Edwards for providing observations and maps of
Podocarpus stands and to Dale Tonkinson (Arthur Rylah Institute) for introductory
information. Steve Fall, Ben Rankin and Tim Crawford (DSE Forestry Swifts Creek) provided
valuable site information. Brian Reese and staff (DSE air desk) arranged helicopter transport
and DSE staff at Swifts Creek assisted with re-fuelling.
The project was funded under the Victorian Bushfire Recovery Program (DSE and Parks
Victoria).
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References
ANBG (2003) http://www.anbg.gov.au/gnp/interns-2003/podocarpus-lawrencei.html
Barker, P.C.J. (1991) Podocarpus lawrencei (Hook. f.): Population structure and fire history at
Goonmirk Rocks, Victoria. Australian Journal of Ecology 16, 149-158.
Bowman, D. M. J. S. and Harris, S. (1995) Conifers of Australia’s dry forests and open
woodlands. In Enright, N.J. and Hill, R.S. (Eds) Ecology of the Southern Conifers.
Melbourne University Press, Melbourne.
Costin, A.B, Grey, M., Totterdell, C.J. and Wimbush, D.J. (1979) Kosciusko Alpine Flora.
CSIRO/Collins, Melbourne.
Edwards, J. (2003) Alpine regrowth after fire. The Clematis 55, 7-9.
Gibson, N., Barker, P.C.J., Cullen, P.J. and Shapcott, A. (1995) Conifers of southern Australia.
In Enright, N.J. and Hill, R.S. (Eds) Ecology of the Southern Conifers. Melbourne
University Press, Melbourne.
Kirkpatrick, J. B. (1983) Treeless plant communities of the Tasmanian high country.
Procroceedings of the. Ecological Society of Australia 12, 61-77.
LCC (1977) Alpine Study Area Report. Land Conservation Council, Victoria.
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