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Home , Burchardia, Dichanthium, Mitchell Grass Downs, Northern Kimberley, Pilbara, Poa poiformis

NVIS Fact sheet MVG 19 –

Australia’s native vegetation is a rich and fundamental • comprise natural areas of , as well as vast areas element of our natural heritage. It binds and nourishes of native grasslands derived from vegetation our ancient soils; shelters and sustains wildlife, protects in which most or all of the tree and shrub cover has been streams, , estuaries, and coastlines; and absorbs removed. The structure and species composition of these carbon dioxide while emitting oxygen. The National derived grasslands may resemble some of those described Vegetation Information System (NVIS) has been developed here, although mostly they are derivatives of MVGs and maintained by all Australian governments to provide 5 and 11 a national picture that captures and explains the broad • were in existence before European colonisation when diversity of our native vegetation. natural temperate lowland grasslands occupied large areas of This is part of a series of fact sheets which the Australian south-eastern , most notably on the southern Government developed based on NVIS Version 4.2 data to tablelands of , basalt plains of western provide detailed descriptions of the major vegetation groups , in southern and in the (MVGs) and other MVG types. The series is comprised of of New South Wales and Victoria a fact sheet for each of the 25 MVGs to inform their use by planners and policy makers. An additional eight MVGs are • in tropical and arid cover extensive black available outlining other MVG types. soil plains in central and northern , the and For more information on these fact sheets, including • may be dominated by grass species with C3 or its limitations and caveats related to its use, please see: C4 photosynthetic pathways or a mixture of both, ‘Introduction to the Major Vegetation Group (MVG) depending on temperature regimes and aridity fact sheets’. • are fire-prone and able to regrow rapidly after being burnt Overview • have species that lack persistent soil seedbanks • Cattle and sheep grazing has been the major land use in Typically, vegetation areas classified under MVG 19 – tussock grassland since settlement. Tussock grasslands: • represent treeless communities dominated by native perennial tussock grasses widely distributed over seven per cent of the Australian through arid, temperate and tropical areas

Temperate Tussock Grasslands of Rytidosperma and Austrostipa species, Ivanhoe, NSW (Photo: B. Pellow) SSD18S.0117 environment.gov.au Facts and figures Structure and physiognomy

• Grasslands are characterized by large perennial tussock MVG 19 - Major Vegetation Group grasses, broad-leaved and lilioid herbs in the inter Tussock grasslands tussock spaces and a lack of woody . In localised 34. Mitchell grass (Astrebla) areas, forbs may dominate the tussock grasses. tussock grasslands • Grasses have modular growth forms that grow as single 35. Blue grass plants in clumps, tufts or bunches, rather than forming a (Dicanthium) and tall continuous or . bunch grass (Vitiveria • The growth and reproductive phenology of C3 and Major syn: Chrysopogon) C4 grasses depends on temperature and photoperiod – Vegetation Subgroups tussock grasslands the C3 grasses grow mainly in spring and autumn and the C4 grasses grow mainly in late spring-early summer, 36. Temperate as soil moisture levels permit. tussock grasslands • Although the dominant grasses are perennial, some 37. Other annual grasses may also be present. tussock grasslands • Some areas of grassland are the result of extensive Closed Tussock Grassland clearing of woodland communities that had a high grass (mid, low) component in the ground layer. The Riverina region of New South Wales is generally considered to have been Typical NVIS Open Tussock Grassland originally dominated by of Acacia pendula structural formations (mid, low) and Atriplex nummularia with both species rapidly eliminated by heavy stock grazing which form extensive Tussock Grassland (mid, secondary grasslands. low) Number of IBRA regions 71 Most extensive in IBRA region Mitchell Grass Downs (Qld (Est. and NT) pre-1750 and Present) Estimated pre-1750 extent 570 001 (km2) Present extent (km2) 527 147 Area protected (km2) 31 674

Astrebla spp. (Mitchell grasses) west of Blackall, Qld (Photo: M. Fagg)

environment.gov.au Indicative species Environment

• The principle families represented in tussock • Climate varies from warm tropical with summer grasslands are , Asteraceae, Fabaceae, Geraniaceae, maximum rainfall to temperate with winter maximum and Chenopodiaceae. rainfall to alpine climates where snow cover may persist • Species composition varies depending on seasonal for several months. conditions and local variations in soils and topography. • Most grasslands fall within the 400 – 1000 mm mean Grasses tend to dominate after summer rainfall or annual rainfall band, but may occur in wetter and flooding, while forbs generally dominate after winter drier climates. rainfall events. • Most grasslands are found on plains, rolling downs, • At continental scale, tropical and arid environments tend undulating plateaus and local depressions. to be dominated by C4 grass species, while C3 grasses • Soils are typically high in clay content, with become important components of the communities in substrates including alluvium, basalt, siltstones and cooler climates. granitoid geology. • C4 grasses Astrebla (Mitchell grass) and Dichanthium • Many grasslands occupy heavy-textured soils that remain (Bluegrass), dominate grasslands of the tropical and arid wet for extended periods after rain. regions, with Chrysopogon (Ribbon grass) and Eulalia • Along local topographic or edaphic gradients, tussock (Browntop) also common. A wide range of smaller grasslands may transition into temperate woodlands, perennial grasses, including species of Iseilema and tropical , and wetlands. Aristida, occupy the spaces between the large tussocks. • Grasslands of the tropical and arid regions (e.g. Blue Forbs and native legumes are also common, being more Grass, Mitchell grass etc) generally occur on black, prevalent in southern areas where annual rainfall is more cracking clay soil plains, mostly in tropical and evenly distributed. subtropical latitudes receiving summer maximum • Tussock grasslands of the temperate south-east rainfall (mean 400 – 900 mm per annum), but may are typically dominated by a mixture of C3 and extend to warm temperate latitudes in the arid zone C4 perennial tussock grasses including species of (mean annual rainfall as low as 250 mm) on landforms Austrostipa, , Chloris, , Rytidosperma such as gilgais or with heavier clay soils. and Themeda. Poa and Themeda dominate in areas of • Temperate tussock grasslands occur in areas with relatively high rainfall e.g. southern Victoria, New relatively low rainfall (mean 400 – 800 mm per South Wales southern tablelands and , year), with semi-arid ecosystems in the New South whereas Chloris, Rytidosperma and Austrostipa Wales Riverina and South Australia at the drier end co-dominate in drier regions including the Riverine of this range. They occur on flat to gently undulating plains and south-central South Australia. Inter-tussock topography on poorly drained clay and clay loam soils of spaces include a variety of forbs including species of relatively high fertility. On the coast they are found on Brachyscome, Burchardia, Chrysocephalum, Cullen, exposed coastal cliffs and headlands and islands. Desmodium, Dianella, Geranium, Ranunculus, Tricoryne Viola, Wahlenbergia and various orchids. On exposed • Other grasslands are found in a range of environments coastal headlands and islands of south-eastern Australia, from Alpine to tropical savannas. Alpine grasslands Themeda triandra, and Sporobolus virginicus occur on elevated plateaus (mostly above 1700 m are the most common dominants. on the mainland, and above 1000 m in Tasmania) receiving more than 1000 mm mean annual rainfall; • A range of other grasslands not dominated by genera soils are relatively fertile organic loams derived from typical of temperate or Mitchell/Blue grass grasslands, substrates such as granodiorite, dolerite, basalt or are included in this MVG. An important component limestone. Western Australian grasslands experience of this group is Alpine grasslands dominated by high temperatures and low irregular rainfall (200 and Poa, with Agrostis, Deyeuxia and Rytidosperma sometimes 350 millimetres per year). The grasslands are present, and C4 species are absent. Another example is found along the coastal sand plains while grasslands in the in Western Australia, where further north in the Kimberley, are found inland on various grasslands of Sorghum, Astrebla, Chrysopogon and flatter lateritic orthent soils. occur, typically described as . Savanna communities with emergent trees over 0.25% crown cover (scattered isolated trees), are assigned to MVG 12.

environment.gov.au Geography through central New South Wales, along the periphery of Blue Grass/Mitchell grasslands in central/northern • Extend from tropical to semi-arid, temperate and Australia, to the northern Kimberley savannas and alpine areas of Australia and include valuable areas for Pilbara Coast. pastoralism (e.g. the Mitchell Grasslands). • Largest area is in Queensland (304 124 km2). • Mitchell grass and Blue grass grasslands occur around the and the of south The below image outlines the location of this MVG group extending to north-west New South in Australia. Wales on the Moree and Liverpool plains, with scattered occurrences in the Victoria River and Kimberley-Pilbara Change region Western Australia. • Temperate tussock grasslands extend along the tablelands • Approximately eight per cent (43 000 km2) cleared since from the New England region in New South Wales European settlement. to the Victorian highlands and basalt lowland plains, • Temperate tussock grasslands have been extensively and west into South Australia. Outliers occur in the cleared for cropping and improved , while Tasmanian midlands and mountain valleys. Grassy balds tropical arid grasslands and other grasslands remain occur in restricted sites in largely uncleared. south-east Queensland and north-east New South • Fragmentation of temperate grassland results in Wales, while coastal forms occur on headlands and a reduced suite of native grasses amid a matrix of offshore islands from north-east New South Wales to introduced species. southern Tasmania. • Grazing by livestock has been the dominant land use of • Other grasslands extend from the Alpine grasslands and tussock grasslands since European settlement, altering herbfields of the Kosciuszko plateau, Victorian Alps, vegetation structure, species composition and soil Tasmania central plateau and southern mountains,

environment.gov.au structure. Severe leads to loss of palatable • Ecotourism including bushwalking and landscape species and soil degradation. scenic values. • Grasslands recover from degradation slowly or not at all, • Pastoralism production, including a substantial in part due to the lack of a persistent soil seedbank in proportion of Australia’s output. many species. • Value to Indigenous communities. • Fire regimes may affect the growth of tussocks and other annual and short-lived perennial grasses and a range of colonising may replace the List of key management issues dominant tussock grasses immediately after a fire. In • Continued small-scale clearing in temperate some systems, infrequent fires may lead to limited gaps tussock grasslands. for seedling, establishment senescence of tussocks or • Total grazing pressure from domestic, feral and native invasion of woody plants, although the latter is mainly a animals, especially during extended drought and around phenomenon in derived grasslands. watering points. • Threats include land clearing, pasture improvement and • Degradation of temperate remnants by other sources of nutrient enrichment, inappropriate fire nutrient-enriched runoff. regimes, and high total grazing pressure. • Soil degradation by overgrazing. • Fire regimes. Key values • Weed control. • Biodiversity including a variety of specialist species and • Impacts of climate change. threatened ecological communities. • Long-term monitoring to inform future • Tussock grasslands provide shelter for a large variety of management strategies. reptiles and small marsupials in Australia.

Alpine grasslands and herbfields Kosciusko National Park, NSW (Photo: D. Keith)

environment.gov.au References McIntyre S, Barrett G.W. (1992) variegation an alternative to fragmentation. Conservation Biology Australian Surveying and Land Information Group (1990) vol. 6, pp. 31 – 37. Atlas of Australian Resources. Volume 6 Vegetation. AUSMAP, Department of Administrative Services, Canberra, Moore C.W.E. (1953) The vegetation of the south-eastern 64pp. & 2 maps. Riverina, New South Wales. II. The disclimax communities. Australian Journal of Botany vol. 1, pp. 548 – 567. Beadle N.C.W. (1981) The Vegetation of Australia. Cambridge Univ. Press, Cambridge, 690pp. Mott J.J. and Groves R.H. (1994) Natural and derived grasslands. In: Australian Vegetation (ed. R.H. Groves) pp. Beard J.S., Beetson, G.R, Harvey J.M. Hopkins A.J.M. and 369 - 392. Cambridge Univ. Press, Cambridge. Shepherd D.P. (2013) The Vegetation of Western Australia at 1:3,000,000 Scale. Explanatory Memoir. Second Edition. National Land and Water Resources Audit (2001) Australian Science Division, Department of Parks and Wildlife, Native Vegetation Assessment 2001. National Land and Water Western Australia. Resources Audit, Canberra, 332pp.

Carter O., Murphy A.M. and Cheal D. (2003) Natural Neldner, V.J., Niehus, R.E., Wilson, B.A., McDonald, Temperate Grassland. Department of Natural Resources & W.J.F. and Ford, A.J. (2014). The Vegetation of Queensland. Environment (Vic.); online at URL: http://www.deh.gov.au/ Descriptions of Broad Vegetation Groups. Version 1.1. biodiversity/publications/grasslands/index.html. Queensland Herbarium, Department of Science, Information Technology, Innovation and the Arts. Fox I.D., Neldner V.J., Wilson G.W., et al. (2001) The Vegetation of the Australian Tropical Savannas. Env. Prot. Victorian Department of Sustainability and Environment Agency, Qld and Tropical Savannas CRC, 2 map sheets and (2004). EVC Bioregion Benchmark for Vegetation 1 legend; online at URL: Quality Assessment http://www.depi.vic.gov.au/ http://savanna.ntu.edu.au/information/. environment-and-wildlife/biodiversity/evc-benchmarks [Accessed June 2015]. Harris S. and Kitchener A. (2005) From to Fjaeldmark. Descriptions of Tasmania’s vegetation. Dept of Primary White A., Orr D., Novelly P., Bastin G. (2014) Tussock Industries, Water and Environment, Hobart. grasslands. In: Biodiversity and Environmental Change Monitoring, Challenges and Direction (eds. Lindenmayer D., Keith D.A. (2004) Ocean Shores to . Burns E., Thurgate N. and Lowe A.) pp. 479 - 518. The native vegetation of New South Wales and the ACT. CSIRO, Victoria. Department of Environment and Conservation (NSW), Hurstville. Data sources Leigh J.H. and Noble J.C. (1972) Riverine Plain of New South Wales: Its Pastoral and Irrigation Development. CSIRO Interim Biogeographic Regionalisation for Australia (IBRA), Division of Plant Industry, Canberra. Version 7.

Lunt I.D, Morgan J.W. (2002) The role of fire in temperate National Vegetation Information System, Version 4.2. lowland grasslands of south-eastern Australia. In: Flammable Collaborative Australian Protected Areas Database – Australia. The fire regimes and biodiversity of a continent. CAPAD 2014 – Terrestrial. (eds. Bradstock R.A., Williams J.E. and Gill A.M.) pp. 177 - 198. Cambridge University Press, Cambridge.

© Commonwealth of Australia, 2017. This fact sheet is licensed by Commonwealth of Australia under a Creative Commons Attribution 4.0 International licence. The views and opinions expressed in this publication are those of the authors and do not necessarily reflect those of the or the Minister for the Environment and Energy.

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