Mvg 5 Eucalypt Woodlands




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MVG 5 - Eucalypt Woodlands

Eastern temperate grassy woodlands Tamworth, NSW (Photo: D. Keith)

Overview

  • Form a transitional zone between the higher rainfall forested margins of Australia (MVG 3) and the open woodlands (MVG 11 and 13), shrublands (MVG 16) and hummock grasslands (MVG 20) of the arid interior.

  • Distributed in an arc from the subtropical Queensland to Tasmania and west to southeast South Australia, with an outlier in south Western Australia. Replaced by MVG 12 at tropical latitudes.

  • Eucalypts are the dominant trees throughout, but species of Acacia or Callitris may occur in a subcanopy.

  • Woodland generally describes ecosystems that contain trees widely spaced with their crowns not touching (Hobbs 2002). The tree layer has a crown cover of 20 - 50% (projective foliage cover 10-30%).

  • Woodland understories in the east are mostly grassy, while those in the west are predominantly shrubby.

  • Temperate eucalypt woodlands are highly fragmented due to clearing for crops and improved pastures in the south-eastern and south-western wheat-sheep belts.

  • The ‘parkland’ landscapes, retaining remnant trees of the original woodlands in the eastern and southern parts of Australia evoke a strong sense of place for many Australians.

Facts and figures

Major Vegetation Group

MVG 5 - Eucalypt Woodlands

Major Vegetation Subgroups

(number of NVIS descriptions)

09. Eastern temperate grassy woodlands ACT, NSW, QLD, VIC SA, TAS

59. Subalpine woodlands ACT, NSW, VIC, TAS

08. Western temperate shrubby woodlands WA



65.Semi-arid floodplain and wadi woodlands NSW, VIC, QLD, NT, SA, WA.

xx. Semi-arid upland and peneplain woodlands NSW, QLD, NT, SA, WA.

Typical NVIS structural formations

Woodland (low, mid)

Number of IBRA regions

80

Most extensive in IBRA region

Est. pre-1750: Brigalow Belt South (Qld and NSW)

Present: Einsaleigh Uplands (Qld)

Estimated pre-1750 extent (km2)

1 362 263

Present extent (km2)

892 920

Area protected (km2)

72 589

Western temperate shrubby woodlands, WA (Photo: D. Keith)

Structure and physiognomy

  • The tree layer has a crown cover of 20 - 50% (projective foliage cover 10-30%) and is typically 10 – 30 m tall (Keith 2004; Lindenmayer et al. 2014).

  • Trees canopy leaf sizes vary from notophyll (20 – 45 cm2) to mesophyll (45 – 150 cm2) and leaves are invariably vertically oriented with essentially identical surfaces.

  • May have a patchy understorey stratum of mostly non-sclerophyllous shrubs, which is more prominent in south-western Australia than in south-eastern Australia.

  • The ground layer is dominated by tussock grasses with forbs, and is essentially continuous in south-eastern Australia, but generally sparse in south-western Australia (Hobbs 2002).

  • Tussock grasses include both C3 and C4 species that vary in dominance depending on temperature, light regimes and aridity.

Indicative flora

  • Eucalypts are dominant throughout, with one to four species represented in a stand, or more species in the northern and western areas of the distribution.

  • Non-eucalypts are uncommon in the tallest tree stratum, but species of Acacia or Callitris may occur in a subcanopy.

  • Woodland composition and understorey vary regionally and with landscape context.

  • Dominated in the east by ‘box’ and ‘ironbark’ eucalypts of section Adnataria within subgenus Symphyomyrtus of Eucalyptus, with some species of section Exsertaria (red gums) and, in the cooler climates, species from section Maidenaria. In the west, however, eucalypt species within section Bisectaria, are dominant.

  • Woodland understories in the east are dominated by a largely continuous groundlayer comprising a mixture of C3 and C4 grasses and herbs, differing markedly from those in the west, which include a greater cover of shrubs and a less conspicuous grass component. The balance of this mixture varies with C4 grasses dominating in warmer and drier climates, and C3 grasses dominating in cooler more humid climates.

  • Five subgroups are recognised, including two that are also represented in MVG 11.

    • Eastern temperate grassy woodlands are dominated by Eucalyptus within subgenus Symphyomyrtus section Adnataria. Some communities include species from section Exsertaria and the genus Angophora. Widespread species include Eucalyptus melliodora, Eucalyptus albens, Eucalyptus blakelyi, Eucalyptus microcarpa, Eucalyptus tereticornis, Eucalyptus crebra, Eucalyptus melanophloia, Eucalyptus viminalis and Eucalyptus ovata (Keith 2004; Victoria Department of Sustainability and Environment 2004; Harris and Kitchener 2005; Neldner et al. 2014). Scattered shrubs include Bursaria spinosa and species of Cassinia and Acacia. Dominant C4 grasses in warmer drier sites include species of Aristida, Bothriochloa, Chloris, Cymbopogon, Eragrostis, Heteropogon, Panicum, Sporobolus and Themeda. C3 grasses characteristic of more mesic or cooler areas include species of Austrodanthonia, Microlaena and Poa. The groundlayer also includes a diversity of forbs in families Asteraceae, Anthericaceae, Campanulaceae, Convolvulaceae and Orchidaceae.

    • Subalpine woodlands typically include eucalypts in section Renantheria within subgenus Eucalyptus. The main high country species are Eucalyptus pauciflora, Eucalyptus stellulata, Eucalyptus niphophila and Eucalyptus coccifera in Tasmania. Grasses are primarily species of Poa, with Agrostis, Austrodanthonia and Deyeuxia, all with C3 photosynthetic pathways. Forbs include species of Acaena, Asperula, Geranium and Stellaria. While grasses and forbs dominate sites with deeper soils, shrubs in families Ericaceae and Fabaceae may be prominent in rocky sites (Keith 2004; Victoria Department of Sustainability and Environment 2004; Harris and Kitchener 2005).

    • Western temperate shrubby woodlands are dominated by species of Eucalyptus in section Bisectaria within subgenus Symphyomyrtus. As well as eucalypts with typical woodland growth forms, this MVG includes trees with ‘mallet’ and ‘marlock’ growth forms. Common species include Eucalyptus loxophleba, Eucalyptus salubris, Eucalyptus salmoniphloia and Eucalyptus wandoo, The understorey is highly variable in structure and composition (Commonwealth Government 2015). The main shrub genera include Allocasuarina, Acacia, Melaleuca, Grevillea, Eremophila, Maireana and Atriplex, with the latter more prominent in drier climates, as well as a number of smaller Eucalypt species (Beard et al. 2013; Commonwealth Government 2015). Where the shrub layer becomes sparse grass-like herbaceous perennials and grasses from the Anthericaceae, Cyperaceae, Dasypogonaceae, Liliaceae and Restionaceae are common (Yates et al. 2000).

    • Semi-arid floodplain and wadi woodlands (also represented in MVG 11) are dominated by species of Eucalyptus in sections Adnataria and Exsertaria in subgenus Symphyomyrtus. Eucalypts such as Eucalyptus coolabah, Eucalyptus largiflorens, Eucalyptus ochrophloia, Eucalyptus populnea, Eucalyptus tereticornis and Eucalyptus camaldulensis are widespread with Eucalyptus microtheca occurring in northern and central Australia. The understorey may consist of a shrub layer of species from the genera Acacia, Dodonaea, Eremophila, Muehlenbeckia, and Rhagodia and the groundlayer has an abundance of forbs, chenopods, graminoids & tussock grass (Keith 2004; Victoria Department of Sustainability and Environment 2004; Beard 2013, Neldner et al. 2014)

    • Semi-arid upland and peneplain woodlands (also represented in MVG 11) include species such as Eucalyptus intertexta, Eucalyptus populnea, Eucalyptus melanophloia Eucalyptus siderophloia (all in section Adnataria of subgenus Symphyomyrtus) and Callitris glaucophylla (Keith 2004). The understorey typically has a shrub layer of genera such as Acacia, Allocasuarina, Dodonaea, Eremophila, Hakea, Myoporum and chenopods (Keith 2004; Neldner et al. 2014). The gound layer is rich in forbs and graminoids including species of Aristida, Astrebla Austrostipa, Chloris, Dichanthium, Enteropogon, Heteropogon, Panicum, Rytidosperma, Abutilon, Alternanthera, Brunoniella, Evolvulus, Fimbristylis, Goodenia, Sida and a range of chenopods (Keith 2004; Neldner et al. 2014).

Environment

  • Occur across a wide range of environments varying in climate, soil type, soil parent material and hydrology (Yates and Hobbs 2000).

  • The climate varies from Mediterranean in south western and southern South Australia to summer rainfall dominant in northern New South Wales and southern Queensland (Hobbs 2002).

  • MVG 5 is most prevalent in regions with 200 – 800 mm mean annual rainfall (Yates and Hobbs (2000).

  • Occurs from sea level to 1800 m in altitude on relatively fertile loam – clay soils on a variety of fine grained sedimentary and igneous substrates.

  • Usually found on the fringes of forested areas and water courses or where soil moisture or nutrients may be limiting for tree growth.

  • The large number of eucalypts and their associated species occur on a wide range of environmental gradients. These relationships have been further complicated by the impact of land use following European settlement.

Geography

  • In south eastern Australia temperate Eucalypt Woodlands form a relatively continuous belt on the inland side of the Great Dividing Range from approximately 27oS in southern Queensland to the lower southeast of South Australia with a narrow strip running north and south of Adelaide (Moore 1970). Within this zone the woodlands occur in a mosaic with areas of grasslands (Moore 1970).

  • In Tasmania eucalypt woodlands are interspersed with grasslands and forests throughout the northeast and in the Midlands as far as 42oS (Moore 1970).

  • Eucalypt woodlands are widespread in south Western Australia and often form a mosaic with heathlands, mallee and salt lakes (Beard 1990).

  • Largest distribution of woodland type in Australia and occurs in all states and territories.

  • Largest distribution is found in Western Australia (219 846 km2).

  • Makes up the largest MVG in New South Wales and Queensland.

Change

  • Approximately 470 000 km2 cleared since European settlement: approximately 34% of the estimated pre-1750 extent cleared accounting for 46% of total clearing in Australia.

  • Temperate woodlands are some of the most extensively cleared, heavily modified and highly degraded vegetation types in Australia (Lindemayer et al. 2014) e.g. less than 3% of the original cover of woodland dominated by White Box/Yellow Box woodlands remains (Gibbons and Boak 2002).

  • An important part of cereal cropping and pastoral zones. The cleared areas are extensive so that the broad fabric of the landscape from a vegetation perspective has been lost.

  • Temperate woodlands are the scene of some of the most dramatic and spectacular examples of ecosystem collapse with thousands of hectares that survived broad-scale clearing affected by secondary tree dieback and salinisation processes (Hobbs 2002). Many are now listed as endangered ecological communities under Australian legislation.

  • In Queensland, New South Wales and Victoria pasture improvement and tree thinning have been extensively employed in the grassy woodlands, while the shrubby understorey of other Eucalypt Woodlands has been removed to increase pasture growth.

  • The shrubby understorey of remnants has often been removed either mechanically, by use of frequent fire or intense livestock grazing. These modified systems have been invaded by exotic species or have their perennial components largely replaced by ephemerals when exposed to overgrazing. In some cases, native vegetation originally mapped as Eucalypt Open Woodlands (MVG 11) may be modified Eucalypt Woodlands.

  • Urban development has encroached on localised areas of woodlands.

  • Modified by pastoral activities and altered fire regimes in many places e.g. in some parts of Western Australia fire frequency changed from once every 40 – 50 years to once every 6 – 8 years following European settlement (Lamont and Downes 1979).

  • Fire regimes in remnant woodlands have changed as a consequence of fragmentation and managing fire hazard to intensive agricultural and urban areas and consequently many of the woodlands have been invaded by aggressive introduced plant species. Examples of woodlands subject to urban and rural pressures include the Cumberland Plain woodlands of western Sydney and roadside remnants in the southwest Australian wheatbelt.

  • Foremost amongst threats to eucalypt woodlands are clearing of vegetation, weed invasion, the fragmentation of woodland areas, inappropriate fire regimes and unsustainable grazing management.

  • Less than 10% remains in secure protected areas with most areas under private or leasehold management

  • Stewardship activities are often spurred on by dieback, the need to control dryland salinisation and recognition that in many of the agricultural landscapes only senescent trees remain.

Tenure

Eucalypt Woodlands mainly occur on leasehold land, freehold land, in protected areas or in state forests:



New South Wales:

leasehold land, protected areas, freehold land and some state forests







Queensland:

largely leasehold and freehold land, some protected areas and state forests

South Australia:

leasehold land, freehold land, some protected areas and little in state forests

Tasmania:

protected areas, state forests and freehold land

Victoria:

protected areas, state forests and some freehold land

Western Australia:

vacant crown land, leasehold land, protected areas, fragmented areas in freehold land and some state forests



Semi-arid floodplain and wadi woodlands (Eucalyptus coolabah) showing post flood regeneration, Culgoa, NSW (D. Keith)

Key values

  • Biodiversity including a variety of charismatic trees, understorey grasses and shrubs, and dependent fauna of one of Australia’s major biomes.

  • Refuge for a wide range of vertebrate and invertebrate species, including threatened species.

  • Ecotourism, including bushwalking, walkways and landscape features.

  • Water balance—much of the area affected by groundwater rise coincides with area of eucalypt woodlands.

List of key management issues

  • Control of clearing, edge effects and disease (e.g. dieback)

  • Grazing by livestock and feral animals.

  • Dryland salinity.

  • Restoring connectivity between remnants (e.g. wildlife corridors).

  • Remnant protection and expansion.

  • Fire regimes.

  • Weed control.

  • Long term monitoring to inform future management strategies.

References

Australian Surveying and Land Information Group (1990) Atlas of Australian Resources. Volume 6 Vegetation. AUSMAP, Department of Administrative Services, Canberra, 64pp. & 2 maps.

Beadle N.C.W. (1981) The Vegetation of Australia. Cambridge Univ. Press, Cambridge, 690pp.

Beard J.S. (1990). Plant life in Western Australia. Kangaroo Press, Kenthurst NSW.

Beard J.S., Beetson, G.R, Harvey J.M. Hopkins A.J.M and Shepherd D.P. (2013) The Vegetation of Western Australia at 1:3,000,000 Scale. Explanatory Memoir. Second Edition. Science Division, Department of Parks and Wildlife, Western Australia

Brooker M.I.H. and Kleinig D.A. (1994) Field guide to Eucalypts, Volume 3. Inkata Press, Sydney, 383pp.

Brooker M.I.H. and Kleinig D.A. (1999) Field guide to Eucalypts, South-eastern Australia, Volume 1, 2nd edition. Bloomings Books, Melbourne, 353pp.

Brooker M.I.H. and Kleinig D.A. (2001) Field guide to Eucalypts, South-western and Southern Australia, Volume 2, 2nd edition. Bloomings Books, Melbourne, 428pp.

Commonwealth Government 2015. Conservation advices - Eucalypt Woodlands of the Western Australian Wheatbelt. Department of the Environment.

Fox I.D., Neldner V.J., Wilson G.W., et al. (2001) The Vegetation of the Australian Tropical Savannas. Env. Prot. Agency, Qld and Tropical Savannas CRC, 2 map sheets and 1 legend; online at URL: http://savanna.ntu.edu.au/information/.

Gibbons P., Boak M. (2002). The value of paddock trees for regional conservation in an agricultural landscape. Ecological Management and Restoration 3, 205 – 210.

Gillison A.N. (1994) Woodlands. In: Australian Vegetation. (ed. R.H. Groves) pp. 227-255. Cambridge Univ. Press, Cambridge.

Harris S. and Kitchener A. (2005) From Forest to Fjaeldmark. Descriptions of Tasmania’s vegetation. Department of Primary Industries, Water and Environment, Hobart.

Hobbs R.J. and Yates C.J., eds. (2000) Temperate Eucalypt Woodlands in Australia. Biology, conservation management and restoration. Surrey Beatty & Sons, Sydney, 430pp.

Hobbs R.J. (2002). Fire regimes and their effects in Australian temperate woodlands In Flammable Australia. The fire regimes and biodiversity of a continent. (ed Bradstock R.A., Williams J.E and Gill A.M.) pp. 305 - 328. Cambridge University Pres, Cambridge.

Keith D. (2004) Ocean Shores to Desert Dunes. The native vegetation of New South Wales and the ACT. Department of Environment and Conservation (NSW), Hurstville.

Lamont B.B., Downes S. (1997). The longevity, flowering and fire history of the grasstrees Xanthorrhoea preissii and Kingia australis. Journal of Applied Ecology 16, 893 – 899.

Lindenmayer D, Prober S., Crane M., Michael D., Okada S., Kay G., Keith D., Montague-Drake R., Burns, E. (2014) Temperate eucalypt woodlands. In. Biodiversity and Environmental Change Monitoring, Challenges and Direction (ed. Lindenmayer D, Burns E, Thurgate N and Lowe A.) pp. 283 - 334. CSIRO, Victoria.

Moore R.M. (1970) South-eastern temperate woodlands and grasslands. In Australian grasslands (ed. Moore R.M.) pp. 169 – 190. Australian National University Press, Canberra.

National Land and Water Resources Audit (2001) Australian Native Vegetation Assessment 2001. National Land and Water Resources Audit, Canberra, 332pp.

Neldner, V.J., Niehus, R.E., Wilson, B.A., McDonald, W.J.F. and Ford, A.J. (2014). The Vegetation of Queensland. Descriptions of Broad Vegetation Groups. Version 1.1. Queensland Herbarium, Department of Science, Information Technology, Innovation and the Arts.

Victoria Department of Sustainability and Environment (2004). EVC Bioregion Benchmark for Vegetation Quality Assessment. http://www.depi.vic.gov.au/environment-and-wildlife/biodiversity/evc-benchmarks [Accessed June 2015]

Yates C.J., Hobbs R.J. (2000) Introduction. In Temperate Eucalypt Woodlands in Australia (ed. Hobbs R.J. and Yates C.J.) pp. 1 - 5. Surrey Beatty & Sons, Sydney.

Yates C.J., Hobbs R.J. and True D.T. (2000) The distribution and status of eucalypt woodlands in Western Australia. In Temperate Eucalypt Woodlands in Australia (ed. Hobbs R.J. and Yates C.J.) pp. 86 - 106. Surrey Beatty & Sons, Sydney.



Data sources

Interim Biogeographic Regionalisation for Australia (IBRA), Version 6.1.

Land Tenure in Australia's Rangelands (1955 to 2000), National Land and Water Resources Audit.

National Vegetation Information System, Version 4.1.

1996/97 Land Use of Australia, Version 2.

Collaborative Australian Protected Areas Database – CAPAD 2004 – Terrestrial.



Species Profile and Threats (SPRAT) database Australian Government Department of the Environment and Heritage; online at URL: http://www.deh.gov.au/cgi-bin/sprat/public/sprat.pl .

Notes

  • See the Introduction to the MVG fact sheets for further background on this series




Subalpine woodlands (Eucalyptus pauciflora) Kosciusko National Park, NSW (Photo: D. Keith)




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