Cool temperate ferny wet sclerophyll forests Dandenong Ranges, Vic




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MVG 2 - Eucalypt Tall Open ForestS (wet sclerophyll forests)



Cool temperate ferny wet sclerophyll forests Dandenong Ranges, Vic (Photo: M. Fagg).

Overview

  • Equivalent to the concept of ‘wet sclerophyll forest’, which encompasses forests with a eucalypt-dominated overstorey and understories dominated by a range of species with ‘mesomorphic’ (non-sclerophyllous) foliage. However, wet sclerophyll forests less than 30 m tall are included in MVG 3.

  • Comprise forests greater than 30 m tall and with projective foliage cover of between 30 and 70% (Ashton and Attiwill 1994).

  • Dominated by Eucalyptus species (Ashton and Attiwill 1994). These vary between tropical and temperate climatic zones and between eastern and western sides of the continent.

  • Contain the tallest tree species in Australia and the tallest flowering plant in the world, Eucalyptus regnans (mountain ash), found only in Tasmania and Victoria.

  • Understorey varies widely, depending on soil types, climate and fire history.

  • Understorey plants include a number of species also found in rainforest (Keith 2004).

  • Infrequently prone to extensive canopy fires, especially at temperate latitudes. Fires liberate resources and create open space that is essential for recruitment and establishment of eucalypt seedlings.

Facts and figures

Major Vegetation Group

MVG 2 - Eucalypt Tall Open Forests

Major Vegetation Subgroups

(number of NVIS descriptions)



03 Subtropical broadleaf wet sclerophyll forests. NSW, QLD

54 Subtropical open wet sclerophyll forests NSW, QLD



Xx Cool temperate ferny wet sclerophyll forests NSW, VIC, TAS.

60 Cool temperate open wet sclerophyll forests ACT, NSW, VIC TAS



Xx Western wet sclerophyll forests WA

Typical NVIS structural formations

Tall open forest

Mid open forest



Number of IBRA regions

29

Most extensive in IBRA region
(Est. pre-1750 and present)

Est. pre-1750 and Present: NSW North Coast

Estimated pre-1750 extent (km2)

40 801

Present extent (km2)

35 344

Area protected (km2)

11 870



Western wet sclerophyll forest, Eucalyptus diversicolor, WA (Photo: B Pellow)

Structure and physiognomy

  • Tall open tree canopy that allows a luxuriant understorey of soft-leaved shrubs, ferns and herbs to develop (Keith 2004). Trees typically have long unbranched boles.

  • At least three structural layers: the tree canopy dominated by eucalypts with 30-70% projective foliage cover and more than 30 m tall; a shrub layer of variable density and height; and a ground layer comprising herbs, ferns and graminoids. In many cases there can be four structural layers with tall shrubs and small trees of non-eucalypt species below the upper tree canopy.

  • Vines and creepers are often a feature of this MVG, especially in subtropical and warm temperate regions.

  • Ferns, both as part of the ground layer, or as tree ferns in the shrub or small tree layer, are also a common feature of this MVG.

  • Patches of rainforest are often embedded within a matrix of tall open forest, the two blend together as intermediate forms in which small rainforest trees form a sub canopy beneath the Eucalypts (Keith 2004).

  • Depending on time since last fire, these forests typically have deep layer of leaf litter and branches shed continually by the dominant eucalypts.

Indicative flora

  • Species composition varies along latitudinal and altitudinal gradients in eastern Australia, while the Western Australian forests share few species with those in the east. These and more subtle distinctions related to soil moisture and substrates separate the five subgroups recognised in MVG 2. Many of the eucalypts that distinguish the tall open forests belong to sections Transversaria or Maidenaria within the subgenus Symphyomyrtus. Most others belong to the ‘green ash’ and ‘peppermint’ subseries within subgenus Eucalyptus (formerly Monocalyptus). At local scales, two eucalypts from the same section rarely co-occur (Pryor et al. 1956), but species turnover along local gradients can be substantial, especially in northern NSW, where large numbers of eucalypt species occur within this MVG. Acacia species are often conspicuous species in the subcanopy. Other shrubs and small trees include species of Asteraceae, Lauraceae, Myrtaceae, Pittosporaceae and Rhamnaceae (Ashton and Attiwill 1994; Keith 2004; Victoria Department of Sustainability and Environment 2004; Harris and Kitchener 2005; Beard et al 2013; Neldner et al. 2014). Conspicuous fern taxa include Cyathea, Dicksonia, Blechnaceae and Dryopteridaceae. Subgroups are characterised by the following features.

  • Subtropical broadleaf wet sclerophyll forests are dominated by Eucalyptus saligna, Eucalyptus grandis and Eucalyptus resinifera from the section Traversaria, as well as Eucalyptus pilularis, Eucalyptus microcorys, Syncarpia glomulifera, Corymbia intermedia and Lophostemon confertus. The understorey includes a diversity of small trees and tall shrubs such as Acacia irrorata, Cryptocarya species, Diospyros australis, Elaeocarpus species, Maytenus species, Guioa semiglauca, Psychotria species, Synoum glandulosum, Alphitonia excelsa, Glochidion ferdinandi, Neolitsea dealbata, Notelaea longifolia and Breynia oblongifolia. Vines include Eustrephus latifolius, Smilax australis, Cissus species, Geitonoplesium cymosum, Hardenbergia violacea, Pandorea pandorana, Hibbertia species and Dioscorea transversa. Ground ferns include Lastreopsis species, Histiopteris species, Cyathea australis, Calochlaena dubia, Asplenium species and Blechnum species. This subgroup is distributed north from the south coast of NSW to southeast Queensland with a disjunct occurrence in the Atherton-Cairns district of northeast Queensland (Keith 2004; Neldner et al. 2014).

  • Subtropical open wet sclerophyll forests are dominated by Eucalyptus pilularis, Eucalyptus siderophloia, Eucalyptus propinqua, Eucalyptus microcorys, Eucalyptus montivaga, Eucalyptus campanulata, Syncarpia glomulifera, Corymbia intermedia and Lophostemon confertus. Shrubs and small trees occur more sparsely than in the preceding subgroup and include Allocasuarina torulosa, Acacia species, Alphitonia excelsa, Breynia oblongifolia, Maytenus species, Notelaea longifolia, Persoonia species and Pittosporum species. Graminoids are prominent in the ground layer and include Imperata cylindrica, Lomandra longifolia, Entolasia stricta, Lepidosperma laterale, Themeda australis and Oplismenus species. Other common ground layer species include the fern Pteridium esculentum, vines such as Eustrephus latifolius, Hardenbergia violacea, and Smilax australis, and herbs including species of Desmodium, Dianella, Geranium and Pratia. The distribution extends from southeast Queensland to southeast NSW (Keith 2004; Neldner et al. 2014).

  • Cool temperate ferny wet sclerophyll forests are primarily associations of Maidenaria and ‘green ash’ eucalypts, including Eucalyptus cypellocarpa, Eucalyptus delegatensis, Eucalyptus denticulata, Eucalyptus fastigata, Eucalyptus obliqua, Eucalyptus nitens and Eucalyptus regnans. Eucalyptus regnans, Eucalyptus obliqua and Eucalyptus globulus are the dominants in Tasmania, while Eucalyptus campanulata is common at high elevations on the New England escarpment., A typically dense layer of small trees and shrubs includes Bedfordia arborescens, Prostanthera lasianthos, and multiple species of Pomaderris, Olearia, Acacia, and Tasmannia. Ferns are abundant and include Dicksonia antarctica, Cyathea australis, Pteridium esculentum, and species of Asplenium, Blechnum, Histiopteris and Polystichum. These forests are abundant in southern, central and northwest Tasmania, the central highlands and East Gippsland regions of Victoria, the foothills and escarpments of southern NSW and the New England escarpment of northern NSW (Ashton and Attiwill 1994; Keith 2004; Harris and Kitchener 2005).

  • Cool temperate open wet sclerophyll forests include Eucalyptus viminalis subsp. viminalis, Eucalyptus radiata, Eucalyptus obliqua, Eucalyptus fraxinoides, Eucalyptus delegatensis, Eucalyptus dalrympleana, Eucalyptus laevopinea, Eucalyptus brunnea and Eucalyptus campanulata. Small trees and shrubs are scattered include species of Fabaceae including Acacia, Lomatia, Leucopogon, Olearia, Persoonia and Trochocarpa. A prominent grassy groundlayer is dominated by tussocks of several species of Poa, Lomandra longifolia, Geranium, Veronica and Viola. These forests are found from Tasmania to the New England tableland in northern NSW (Keith 2004; Harris and Kitchener 2005).

  • Western wet sclerophyll forests are dominated by Eucalyptus diversicolor in pure stands or in mixed stands with Corymbia calophylla, Eucalyptus guilfoylei, Eucalyptus jacksonii and Eucalyptus marginata A small tree layer of species such as Angonis flexuosa, Allocasuarina decussata and Banksia species may be present under which a layer of shrubs such as Trymalium spatulatum, Chorilaena quercifolia, Hovea elliptica and Acacia pentadenia may occur. These unique forests are restricted to the Warren bioregion, a small area of far southwestern Australia (Beard et al. 2013).

Environment

  • Distribution of this MVG is controlled primarily by high, reliable rainfall and dominates regions receiving between 1500mm and 2000 mm per year with at least 50 mm in the driest season (Ashton and Attiwill 1994). As mean annual rainfall declines below 1500 mm, MVG 2 is increasingly confined to topographically sheltered situations (Wood et al. 2014).

  • The tall forests of Western Australia occur in a climatically marginal climate where mean annual rainfall is between 1000 and 1400 mm per year with the driest month having a mean of >15 mm (Churchill 1968).

  • Tall open eucalypt forests grow on moderately fertile soils often with clay and silt particles dominating the texture (Keith 2004).

  • Produces enormous quantities of leaf litter which accumulates on the forest floor (Keith 2004).

  • The cool temperate wet sclerophyll forests experience some of the most intense wildfires on earth. These typically recur on century time scales coinciding with prolonged periods of extreme hot dry weather and strong winds. At subtropical latitudes, fire weather is less severe and fires may only scorch the tree canopy.

Geography

  • Occurring in high rainfall areas from southeast Queensland south to Tasmania with outliers in north-eastern Queensland and south-western Australia (Keith 2004).

  • Tall eucalypt forests have a relatively narrow ecological range comprising only 4% of the 147 million ha of forest in Australia (Wood et al. 2014).

  • Largest area is in New South Wales (17 788 km2).

Change

  • Approximately 13% of the estimated pre-1750 extent has been cleared, accounting for less than 1% of total vegetation clearing in Australia.

  • Clearing has been primarily for forestry, agriculture and dams.

  • The early management of Australian forests was primarily based on timber production. Extensive areas of accessible forest are now in a range of regrowth states following timber extraction. More recently governments have sought to manage forest areas sustainably for a wider set of values, including biodiversity, water catchment and recreation.

  • Many tall open forests have the capacity to re-establish after clearing (in a simplified state) and provide multiple values for the community (e.g. regrowth karri forest around Pemberton cleared over 100 years ago and now regrowing).

  • Potentially vulnerable to changes in climate patterns through increased temperature, decreased rainfall and the effect of the increased occurrence of extreme weather on fire regimes (Wood et al. 2014).

  • While risks posed by clearing and unsustainable logging are declining, weed invasion is an ongoing legacy of earlier disturbances and fires continues to be a major management issue.

  • Emerging threats include forest diseases and pest outbreaks such as brown rot in Western wet sclerophyll forests, myrtle rust disease and bell miner related dieback in the subtropical forest subgroups.

  • Fire management remains problematic, partly because suitable conditions for prescribed fires are extremely limited between prevailing conditions that are too wet to support fire propagation and extreme conditions in which fires cannot be safely controlled (Lindenmayer 2009)

Tenure

Most of Australia’s remaining tall open forests occur within protected areas or state forests.



New South Wales:

central north areas on freehold land along river courses; coastal areas in protected areas and state forests

Queensland:

protected areas and state forests, some freehold land

Tasmania:

protected areas and state forests, some freehold land

Victoria:

protected areas and state forests, some freehold land

Western Australia:

protected areas and state forests, very small areas on freehold land

Key values

  • Biodiversity that includes rich and varied plant communities unlike any others in the world.

  • Highly diverse bird communities.

  • Water catchments.

  • Geodiversity since they occur across a range of locations and site conditions.

  • Remnant populations of a wide range of vertebrate and invertebrate fauna species.

  • Timber production.

  • Major carbon sinks (Keith et al 2009)

  • Ecotourism, including bushwalks, wilderness experiences and tree-top walks (e.g Nornalup Western Australia and Tahune in southern Tasmania).

  • The public have placed a high value on the cultural and heritage values associated with the stature of the larger and taller trees in these communities (e.g. Bird tree in Camden Haven, Gloucester and Diamond tree lookouts near Pemberton and Manjimup).

List of key management issues

  • Adoption of evidence based approaches on new harvesting practices applicable to the ecology of forests being managed (Wood et al. 2014)

  • Management of hollow bearing trees and associated populations of cavity-dependent animals (Wood et al. 2014).

  • Fragmentation, edge effects, isolation and faunal barriers caused by clearing and infrastructure such as roads/powerlines.

  • Tourist/visitor management.

  • Fire regimes and ignitions in surrounding landscapes. Fire is used as a tool in some areas for regenerating forests, while in other areas the intensity and frequency of fire is critical to the persistence of forest flora and fauna. In cool temperate forests, most of the dominant tree species are killed by canopy fires and rely on seed for regeneration. Frequent canopy fires may lead to long-lasting elimination of trees and transformation of eucalypt forests to acacia forests (Ashton 1981).

  • Disease and pest management.

  • Legacies of weed infestations from past clearing and logging, aggressive vines, lantana, privets.

  • Long term monitoring to inform future management strategies.

References

Ashton D.H (1981) Fire in tall open forests (wet sclerophyll forests). In: Fire and the Australian biota. (eds. A. M. Gill, R.H. Groves and I. R. Noble) pp. 339-366. Australian Academy of Science, Canberra.

Ashton D.H and Attiwill P.M. (1994) Tall open-forests. In: Australian Vegetation. (ed. R.H. Groves) pp. 157-196. Cambridge Univ. Press, Cambridge.

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., 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. (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.

Churchill D.M (1968) The distribution and prehistory of Eucalyptus diversicolor F.Muell., E. marginata Donn ex Sm. and E. calophylla R.Br. in relation to rainfall. Australian Journal of Botany 16, 125 – 151.

Harris S. and Kitchener A. (2005) From Forest to Fjaeldmark. Descriptions of Tasmania’s vegetation. Deptartment of Primary Industries, Water and Environment, Hobart, 432pp.

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

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

Keith H., Mackey B.G., Lindenmayer D.B. (2009) Re-evaluation of forest biomass carbon stocks and lessons from the world’s most carbon-dense forests. Proceedings of the National Academy of Sciences of the Unite States of America 106, 11635 – 11640.

Kirkpatrick J.B., Peacock R.J., Cullen P.J. and Nyland M.G. (1988) The Wet Eucalypt Forests of Tasmania. Tasmanian Conservation Trust, Hobart, 156pp.

Lindemayer D.B. (2009) Forest Patterns and Ecological Process: A synthesis of 25 years of research (CSIRO Publishing, Melbourne).

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

Pryor L.D., Chattaway M.M., Kloot N.H. (1959) The inheritance of wood and bark characters in Eucalyptus. Australian Journal of Botany 4, 216 – 239.

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 2014]

Wood S, Bowman D., Prior L., Lindenmayer D., Wardlaw T. and Robinson R. .(2014). Tall eucalypt forest. In. Biodiversity and Environmental Change Monitoring, Challenges and Direction (Ed. Lindenmayer D, Burns E, Thurgate N and Lowe A.) pp. 519 - 570. CSIRO, Victoria

Data sources

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

National Vegetation Information System, Version 4.1.

1996/97 Land Use of Australia, Version 2.



Collaborative Australian Protected Areas Database – CAPAD 2004 – Terrestrial.

Notes

  • Previously, the greatest area of this MVG was estimated to be in Victoria. Revisions of height class data in NVIS version 3 has reduced its extent in Victoria.

  • Increases in present extent arise largely from improved NVIS 3 data in New South Wales.

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




Subtropical open wet sclerophyll forest, northern NSW (D. Keith)



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