Characteristics of Threatened Communities

Grey Box - Buloke Grassy Woodland Community

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Grey Box - Buloke Grassy Woodland Community

The Grey Box - Buloke Grassy Woodland Community is a mainly grassy woodland found on flat or very gently undulating plains in northern Victoria and a few places in central Victoria. It tends to develop in the absence of fire on sites with relatively fertile, fine-grained soils.

Grey Box (Eucalyptus microcarpa) is usually the structurally dominant tree over a lower stratum of Buloke (Allocasuarina luehmannii). Where fire is absent over a very long period, buloke may become the dominant species. The ground layer is mainly grasses such as Bristly Wallaby-grass (Danthonia setacea = Rytidosperma setaceum), Squirrel-tail Fescue (Vulpia bromoides), Soft Brome (Bromus hordeaceous = B. hordeaceus), Windmill-grass (Chloris truncata), Common Wheat-grass (Elymus scaber = E. scaber var. scaber), occasionally Kangaroo Grass (Themeda triandra) and (rarely) Tussock-grass (Poa sieberiana). Although a shrub layer is usually lacking, a scattering of wattles is present at some sites, including Deane’s Wattle (Acacia deanei), Gold-dust Wattle (A. acinacea) and Golden Wattle (A. pycnantha) and a few other shrubs such as Drooping Cassinia or ‘Chinese Scrub’ (Cassinia arcuata).

Herb-rich Plains Grassy Wetland (West Gippsland) Community

The Herb-rich Plains Grassy (West Gippsland) Community typically occurs in shallow (less than 50 cm deep) seasonal wetlands that fill in winter and spring and are dry by summer. Some may retain water for longer periods, but typically only have surface water for up to six months. The community contains a rich plant association of grasses, sedges and aquatic herbs.

This community is characterized by a strong zonation pattern from emergent sedges, grasses and amphibious herbs in the fringing/littoral zone, through to deeper water dominated by submergent species together with a few sedges. Species typical of the fringing zone, and subject to shallow inundation, include Common Tussock-grass (Poa labillardierei = P. labillardierei var. labillardierei) and/or Soft Twig Sedge (Baumea arthrophylla), and Common Spike-sedge (Eleocharis acuta), in association with Brown-back (Danthonia duttoniana = Rytidosperma duttonianum) and Wetland Wallaby-grass (D. semiannularis = Rytidosperma semiannulare). Other sedges, including Basket Sedge (Carex tereticaulis), or Fen Sedge (C. gaudichaudiana) may be locally abundant. This zone also supports a suite of other species including Joint-leaf Rush (Juncus holoschoenus), Running Marsh-flower (Villarsia reniformis), Prickfoot (Eryngium vesiculosum), Floating Club-sedge (Isolepis fluitans), Small Loosestrife (Lythrum hyssopifolia), Poison Lobelia (Lobelia pratoides) and Small Spike-sedge (Eleocharis pusilla). In ungrazed or infrequently grazed situations, this fringing zone may include Swamp Everlasting (Bracteantha sp. aff. subundulata), Pale Swamp Everlasting (Helichrysum aff. rutidolepis = Coronidium aff. scorpioides (Lowland Swamps), Milky Beauty Heads (Calocephalus lacteus), Billy Buttons (Craspedia canens), and Swamp Daisy (Brachyscome cardiocarpa). The central zone, when inundated, is dominated by Common Spike Sedge (Eleocharis acuta) in association with Australian Sweet Grass (Glyceria australis) and/or Veined Swamp Wallaby-grass (Amphibromus nervosus). Other plants that may be abundant in this zone include Water Purslane (Neopaxia australasica), Running Marsh-flower (Villarsia reniformis), Soft Twig-sedge (Baumea arthrophylla), Soft Bog-sedge (Schoenus tesquorum), Floating Pondweed (Potamogeton tricarinatus = Potamogeton cheesemanii), Water Ribbons (Triglochin procerum spp. agg.), River Buttercup (Ranunculus inundatus) and Water-milfoil (Myriophyllum spp). If present, emergent trees of River Red Gum (Eucalyptus camaldulensis) or Swamp Gum (E. ovata) may be scattered throughout the wetland or on higher ground fringing the wetland. Shrubs, where present, tend to be sparse and only on the fringe of the community. These may include Blackwood (Acacia melanoxylon), Golden Spray (Viminaria juncea), Swamp Paperbark (Melaleuca ericifolia) and Prickly Tea-tree (Leptospermum continentale).

It is estimated that less than 70 ha of this community still exists, including degraded areas. Remnants occur at Barnbam Swamp at Lyndhurst, along the fringe of the former Carrum Carrum Swamp, on private land at Braeside Park, and along rail reserves between Dandenong and Cranbourne, Dandenong and Berwick, and Clyde and Tooradin. Remnants of this community continue to be under pressure from ongoing urban development in the eastern and south–eastern growth corridors of Melbourne.

Limestone Grassy Woodland Community

The Limestone Grassy Woodland Community is a somehat variable eucalypt woodland that occurs on sites with moderate fertility on undulating hills, largely on limestone-derived soils. The vegetation structure varies from open woodland to open forest over a diverse ground layer of grasses and herbs.

The most common trees are Manna Gum (Eucalyptus viminalis = E. viminalis subsp. viminalis) and Yellow Box (Eucalyptus melliodora) with other species including Snow Gum (Eucalyptus pauciflora). There are occasional individuals of Kurrajong (Brachychiton populneus = Brachychiton populneus subsp. populneus) and the nationally-vulnerable East Gippsland endemic, Limestone Blue Wattle (Acacia caerulescens). The understorey is characterized by a tall shrub layer of low diversity that typically includes such species as Blackwood (Acacia melanoxylon), Lightwood (A. implexa), Limestone Blue Wattle (A. caerulescens), Tree Violet (Hymenanthera dentata = Melicytus dentatus), Sweet Bursaria (Bursaria spinosa = Bursaria spinosa subsp. spinosa) and Drooping Sheoak (Allocasuarina verticillata). Herbs are the most abundant and structurally obvious life-forms in this community. The ground layer is dominated by grasses, with Kangaroo Grass (Themeda triandra) the most common. Other grasses present may include Red-leg Grass (Bothriochloa macra), Common Tussock-grass (Poa labillardierei = P. labillardierei var. labillardierei), Soft Tussock-grass (P. morrisii) and Blady Grass (Imperata cylindrica). A variety of herbs is commonly present, including Cinquefoil Cranesbill (Geranium potentilloides = G. potentilloides var. potentilloides), Bidgee-widgee (Acaena novae-zelandiae), Sheep’s Burr (Acaena echinata), Hairy Solenogyne (Solenogyne gunnii), Small-leaf Bramble (Rubus parvifolius), Kidney Weed (Dichondra repens), Grassland Wood-sorrel (Oxalis perennans) and Maori Bedstraw (Galium propinquum = Galium leiocarpum).

Once widespread and locally extensive, this community now appears to be restricted to the limestone areas of the Buchan and Murrindal River valleys, which are largely cleared for agriculture with the community remnants usually being heavily grazed.

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