Characteristics of Threatened Communities

Caltha introloba Herbland Community

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Caltha introloba Herbland Community

A Caltha introloba Herbland Community is a very open herbland dominated by either Alpine Marsh Marigold (Caltha introloba) or Dwarf Cushion Sedge (Oreobolus pumilio = Oreobolus pumilio subsp. pumilio). The community is characterized by having very little vegetation cover, typically less than 30%, and by occurring as relatively small patches between 250 and 1000 m2. Dwarf Cushion Sedge can form distinctive cushions that progressively die from the centre outwards, creating ‘fairy rings’. Hummocks of Sphagnum moss are often found at the borders of the community, which grades into moss bed downhill and Epacris glacialis heathland or one of the snowpatch communities uphill. Rare species are often associated with the community and include species such as Craspedia sp. A Thompson (1981) = Craspedia alba , Deschampsia caespitose = Deschampsia caespitosa, Deyeuxia affinis, Epacris glacialis, Erythranthera australis = Rytidosperma australe, Juncus antarcticus = Juncus antarcticus, Parantennaria uniceps = Parantennaria uniceps, and Utricularia monanthos. Many of these rare species are restricted to the Bogong High Plains.

This community occupies a very specialised and localised type of habitat. It mainly occurs on flat rocky outwashes of some snowpatch communities in the sub-alpine zone, but has also been recorded within steep snowpatches in the alpine zone above 1800m ASL. The openness of the community is maintained by the continuous and abundant flow of water from the snowpatch during the spring/summer thaw. In Victoria this community is known only from the Bogong High Plains.

Central Gippsland Plains Grassland Community

The Central Gippsland Grassland Community is dominated by Kangaroo Grass (Themeda triandra) and includes a range of native herbs including Golden Weather-glass (Hypoxis hygrometrica), Common Everlasting (Helichrysum apiculatum = Chrysocephalum apiculatum, Chrysocephalum vitellinum and Chrysocephalum sp. 1), Yellow Rush-lily (Tricoryne elatior) and Common Rice-flower (Pimelea humilis). Trees are rare although, in some places, there are thickets of Drooping She-oak (Allocasuarina verticullata), Burgan (Kunzea ericoides) and saplings of Forest Red Gum (Eucalyptus tereticornis).

The community is extremely restricted in distribution; it is estimated that less than 20 to 30 ha remain. Remnants are currently known only from small areas along the Melbourne to Bairnsdale rail-line, on the disused Heyfield to Maffra rail-line and in a few local Gippsland cemeteries (e.g. Briagolong, Toongabbie and Rosedale). Degraded remnants also occur along a few roadsides east of Toongabbie.

Coastal Moonah (Melaleuca lanceolata subsp. lanceolata) Woodland Community

The Coastal Moonah Woodland Community is open grassy woodland that is dominated by Moonah (Melaleuca lanceolata ssp. lanceolata = Melaleuca lanceolata) and found along parts of the Victorian coastline.

Commonly associated species are Wirilda (Acacia retinodes var. uncifolia = Acacia uncifolia), Coast Swainson-pea (Swainsona lessertiifolia), Thyme Rice-Flower (Pimelea serpyllifolia = P. serpyllifolia subsp. serpyllifolia), Coast Tea-tree (Leptospermum laevigatum), Coast Beard-heath (Leucopogon parviflorus) and Kidney-weed (Dichondra repens). Other associated species include various grasses and sedges.

Coastal Moonah Woodlands tend to occur on high-level dunes along the coast where soils are strongly alkaline and developed on moderately organic aeolian sands or on dune calcarenites. The community has a scattered distribution between Phillip Island and Lorne, with disjunct occurrences west of Portland. (The Moonah-dominated communities of north-central and north-western Victoria, although dominated by that species, are floristically distinct from Coastal Moonah Woodland.)

Cool Temperate Mixed Forest Community

Cool Temperate Mixed Forest is a structurally complex forest that has an upper canopy of eucalypts above an understorey layer of smaller trees of species that characterise Cool Temperate Rainforest communities. Its main tree species alter from east to west across Victoria. In the east the rainforest species include Black Oliveberry (Elaeocarpus holopetalus) and Southern Sassafras (Atherosperma moschatum). To the west their composition changes: Black Oliveberry is found in East Gippsland only, Southern Sassafras extends from East Gippsland to the Central Highlands and Myrtle Beech (Nothofagus cunninghamii) from the Central Highlands to the Otway Ranges. Blackwood (Acacia melanoxylon) may occur in all localities. A similar pattern is seen in the eucalypt species, with Cut-tail Ash or Brown-barrel (E. fastigata) only in East Gippsland, Errinundra Shining Gum (Eucalyptus denticulata), Shining Gum (E. nitens) and Tingaringy Gum (Eucalyptus glaucescens) from East Gippsland to the Central Highlands, and Mountain Ash (E. regnans) from Gippsland to the Otway Ranges. Other acacias such as Silver Wattle (Acacia dealbata) may also be present. Characteristic ground and epiphytic plants include Mountain Pepper (Tasmannia lanceolata), Tall Sedge (Carex appressa) and a variety of ferns such as Soft Tree-fern (Dicksonia antarctica), filmy-ferns (Hymenophyllum spp.), water-ferns (Blechnum spp.) and Kangaroo Fern (Microsorum pustulatum), together with abundant bryophytes and lichens. The deeply-shaded forest floor usually has insufficient light to allow eucalypt regeneration.

Given sufficient time, and if bushfires do not intervene, the eucalypts of the overstorey gradually senesce and die and the community as a whole develops into Cool Temperate Rainforest (q.v.). Cool Temperate Mixed Forest can therefore be regarded as a seral or successional stage of Cool Temperate Rainforest that typically develops after rainforest experiences severe fire damage and persists until the community reaches a climax phase.

Cool Temperate Mixed Forest (CTMF) has a very limited distribution within Victoria. It occurs in parts of the Central Highlands, the Toorongo Plateau of north Gippsland and the East Gippsland uplands (e.g Errinundra Plateau), largely at montane elevations (900–1200 metres), often in saddles on mountain plateaus and on cool, permanently moist valley sides, and in gullies. CTMF also occurs in the Otway Ranges and probably in the Strzeleckis. It frequently occurs immediately adjacent to Cool Temperate Rainforest, particularly in the Central Highlands where, commonly but not exclusively, ribbons of CTMF occur on either side of the narrow strips of rainforest along gully bases. The need for sufficiently moist conditions for its rainforest component coupled with the drier soils required for eucalypt establishment means that CTMF is often distributed between permanently waterlogged ground near streams and ground that dries out in summer/autumn, thus setting the boundary conditions for the lower and upper edges of the CTMF ribbons.

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