Characteristics of Threatened Communities

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Fen (Bog Pool) Community

The Fen (Bog Pool) Community is considered interdependent with the Alpine Bog Community. It is characterized by a suite of taxa that establish in pools of standing water within the boggy moss bed of the Alpine Bog Community. The fen community tends to be dominated by sedges (due to presence of surface water) and therefore is structurally different from the Alpine Bog Communities, which are typically dominated by Sphagnum. The characteristic species are the Fen Sedge or Tufted Sedge (Carex gaudichaudiana), Mat Water-milfoil (Myriophyllum pedunculatum = M. pedunculatum subsp. pedunculatum), Dwarf Buttercup (Ranunculus millanii) and Mud Pratia (Pratia surrepens = Lobelia surrepens). The pools usually have permanent water though, at the end of a dry summer, the free water may disappear while the peaty soil remains very damp.

The following additional species may be found in the fens, though not necessarily always: Baw Baw Daisy (Brachyscome obovata), Tufted Hairgrass (Deschampsia caespitosa), Willow Herb (Epilobium gunnianum), Bog Carraway (Oreomyrrhis ciliata = Chaerophyllum australianum), Star Sedge (Carex echinata), Broad-leaf Flower-rush (Carpha nivicola), Spreading Rope Rush (Empodisma minus), Alpine Clubsedge (Isolepis crassiuscula), Sickle Leaf Rush (Juncus falcatus), and Sphagnum Moss species (Sphagnum cristatum and Sphagnum novozelandicum).

Fen (Bog Pool) Community occurs where there are semi-permanent to permanent pools of water along the wettest sections of watercourses and on flatter areas of valley floors, where they are sustained through groundwater discharge. This community is represented in Victoria by a small number of fragmented and isolated remnants scattered across the Australian Alps in alpine, subalpine and montane environments, typically above the climatic tree-line (at or above 1200 m ASL). The community may also occur at lower altitudes in areas known as ‘frost hollows’ that limit the establishment of trees within the community. The rarity of this community may be a reflection of the comparative scarcity of near-permanent pools in the alpine environment.

Forest Red Gum Grassy Woodland Community

The Forest Red Gum Grassy Woodland Community is a type of woodland found at a number of sites in Gippsland. The community is characteristically dominated by Forest Red Gum (Eucalyptus tereticornis = E. tereticornis subsp. mediana), often with co-dominant Red Box (E. polyanthemos). Coast Grey Box (E. bosistoana) occurs towards the coast, while Apple Box or But-But (E. bridgesiana) is often co-dominant on sandy sites. Beneath the eucalypts, there are often scattered small trees of Lightwood (Acacia implexa), and groves of Black She-oak (Allocasuarina littoralis) in some places.

The herbaceous understorey is co-dominated by a variety of species. Dominant grasses include Weeping Grass (Microlaena stipoides = M. stipoides var. stipoides) and Wallaby Grass (Danthonia racemosa = Rytidosperma racemosum), often with Kangaroo grass (Themeda triandra) and/or Veined Spear Grass (Stipa rudis = Austrostipa rudis subsp. rudis). Thatch Saw Sedge (Gahnia radula) is abundant on some sites. Dominant forbs include Kidney-weed (Dichondra repens) and Stinking Pennywort (Hydrocotyle laxiflora), together with an array of perennial and annual plant species.

This community occurs primarily on public land on a small number of sites between 5 and 400 ha in area (approximately 650-700 ha in total), not all of which are managed primarily for conservation purposes. Intact remnants occur within the Moormurng Flora and Fauna Reserve near Bairnsdale, Providence Ponds Flora and Fauna Reserve, the Knob Recreation Reserve near Stratford, Stratford Highway Park, Briagolong Forest Reserve, and the Blond Bay Wildlife Reserve at Lake Victoria. Smaller remnants, many of which are quite degraded, exist in other streamside and bushland reserves.

Granite Foothills Spring Wetland (North-east Victoria) Community

The Granite Foothills Spring Wetland (North-East Victoria) Community is a type of community that develops in scattered sites on soaks and along drainage lines from soaks on the lower slopes of granite foothills in north-eastern Victoria, chiefly in and around the Warby Ranges and the Chiltern-Mt. Pilot Parks. The groundwater that feeds these wetlands emerges seasonally, normally during the spring months, from aquifers through the fragmented granite base rock of the hills, usually waterlogging the soil for several months extending into summer. Since European settlement most of these sites have been used by landholders as water sources for stock, often with concomitant vegetation clearing and the construction of dams and stock channels; commonly relatively little of the original community remains, and weed infestation is common.

The composition of the spring wetland community reflects its disturbance history, with relatively few sites being in good condition. Where intact vegetation remains or has redeveloped, this is typically structured into zones that radiate outwards around the source of moisture. In low disturbance sites, the wetter centre commonly supports many species of sedges and rushes, surrounded by a shrubby woodland at the outer edge of which is a low herbland up to the edge of the waterlogged zone.

The central zone is often dominated by species of rush (Juncus). In the woodland zone the overstorey trees, where they remain, are commonly Warby Swamp Gum (Eucalyptus cadens), Blakely’s Red Gum (E. blakelyi) or, occasionally, Long-leaf Box (E. goniocalyx/nortonii). At the more intact sits the shrub layer often contains Prickly Tea-tree (Leptospermum continentale) and (more rarely) Golden Spray (Viminaria juncea). The outer herbland is species-rich and may include Fairies Aprons (Utricularia dichotoma), Swamp Isotome (Isotoma fluviatilis = Isotoma fluviatilis subsp. australis), Matted St John’s Wort (Hypericum japonicum), Small Mud-mat (Glossostigma elatinoides), Pale Sundew (Drosera peltata subsp. peltata), Common Bog-sedge (Schoenus apogon) and Slender Aphelia (Aphelia gracilis). Several threatened species listed under the Flora and Fauna Guarantee Act may occur in this community, including the Warby Swamp Gum, Narrow Goodenia (Goodenia macbarronii), Purple Diuris Orchid (Diuris punctata) and the Rugose Toadlet (Uperoleia rugosa). The proportion of annual weeds such as Cat’s Ear (Hypochoeris radicata = Hypochaeris radicata) and Lesser Quaking-grass (Briza minor) in the community can indicate the amount of past disturbance.

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