Biodiversity Assessment Technical Report

APPENDIX C: Descriptions of Ecological Vegetation Classes occurring in the Victorian Central Highlands

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APPENDIX C: Descriptions of Ecological Vegetation Classes occurring in the Victorian Central Highlands

Dry Sub-alpine Shrubland

Dry Sub-alpine Shrubland is a sparse to dense shrubland occurring on north-facing slopes and in saddles on the Baw Baw Plateau, often in the vicinity of granite tors. The shallow soils and the extreme exposure to wind may inhibit the establishment of trees and even shrubs on some sites.

Characteristic shrubs include Dusty Daisy-bush (Olearia phlogopappa), Alpine Orites (Orites lancifolia), Cascade Everlasting (Helichrysum secundiflorum) and Mueller's Bush-pea (Pultenaea muelleri).

The herbaceous ground layer, which may be quite dense if the shrubs are sparse, is characterised by Mountain Woodruff (Asperula gunnii), Short-stem Sedge (Carex breviculmis), Silver Daisy (Celmisia asteliifolia), Alpine Wallaby-grass (Danthonia nudiflora) and Australian Carraway (Oreomyrrhis eriopoda).

Fire may have been a factor in generating this ecological vegetation class, which contains a curious mixture of herbs of higher altitudes in conjunction with shrubs normally from lower altitudes. The patchiness of the shrub layer reinforces this conclusion.

Damp Sub-alpine Heathland

Damp Sub-alpine Heathland usually occurs in an intermediate band between Dry Sub-alpine Shrubland and Wet Sub-alpine Heathland, or on raised areas within Wet Sub-alpine Heathland.

The dense shrub layer includes Alpine Star-bush (Asterolasia trymalioides), Alpine Grevillea (Grevillea australis), Scaly Everlasting (Helichrysum hookeri), Snow Heath (Epacris petrophila) and Alpine Orites (Orites lancifolia). The soils, which are deeper and wetter than those of Dry Sub-alpine Shrubland, support a ground layer which includes Spreading Rope-rush (Empodisma minus), Soft Tussock-grass (Poa hiemata), Mountain Woodruff (Asperula gunnii) and Alpine Podolepis (Podolepis robusta).

Wet Sub-alpine Heathland

The wettest sites in the depressions and gully heads of the Baw Baw Plateau, Lake Mountain and Mt Bullfight support an open to very dense heathland characterised by the following shrubs: Candle Richea (Richea continentis), Swamp Heath (Epacris paludosa), Alpine Baeckea (Baeckea gunniana), Drumstick Heath (Epacris breviflora) and Mountain Daisy-bush (Olearia algida).

This ecological vegetation class would include most sites commonly known as alpine or Sphagnum bogs. The deep, peaty, sodden soils are usually covered by a layer of Sphagnum moss (Sphagnum spp.). Other characteristic ground layer species include Spreading Rope-rush (Empodisma minus), Matted Nertera (Nertera granadensis), Alpine Astelia (Astelia alpina) and Mountain Gentian (Gentianella diamensis). The underlying soils accumulate organic material due to slow rates of decomposition, which can be attributed to low temperatures and anaerobic conditions.

Large volumes of water are retained in the moss and peaty soil, seeping downslope until small trickles and streams form. Steeper-sided gullies frequently descend from the outlets of these bogs, often supporting Montane Riparian Thicket (see below).

Sub-alpine Woodland

This community forms a woodland or forest which occurs on slopes above 1200 m, on relatively free-draining soils. Usually dominated by Snow Gum (Eucalyptus pauciflora), the understorey may variously consist of a rich suite of grasses and herbs, or a dense layer of woody shrubs such as Mueller's Bush-pea (Pultenaea muelleri), Alpine Oxylobium (Oxylobium alpestre), Alpine Pepper (Tasmannia xerophila) and Lilac Berry (Trochocarpa clarkei).

An interesting variant of this community is found on Mt Useful, where the Ash-mallee (Eucalyptus kybeanensis) occurs with Alpine Wattle (Acacia alpina), Drooping Beard-heath (Leucopogon gelidus) and a rare, as yet unnamed species of Broom-heath (Monotoca sp. aff. elliptica [alps]). Another unusual record is of Spinning Gum (Eucalyptus perriniana), which occurs north of Mt Whitelaw.

Montane Dry Woodland

The drier, more exposed aspects of the mountain slopes support Montane Dry Woodland, a woodland or forest from 15 to 25 m in height.

Characteristic trees include Broad-leaf Peppermint (Eucalyptus dives), Candlebark (Eucalyptus rubida) and Narrow-leaf Peppermint (Eucalyptus radiata). Snow Gum (Eucalyptus pauciflora) is often present at higher altitudes.

Other notable eucalypts found in this community include Brittle Gum (Eucalyptus mannifera), which is at the western limit of its distribution, and the uncommon Bogong Gum (Eucalyptus chapmaniana), both of which are found in the Woods Point/upper Goulburn area.

Characteristic shrubs include Common Cassinia (Cassinia aculeata), Moth Daisy-bush (Olearia erubescens), and Gorse Bitter-pea (Daviesia ulicifolia). Frequently present in the ground layer are Prickly Starwort (Stellaria pungens), Spiny-headed Mat-lily (Lomandra longifolia), Pink-bells (Tetratheca ciliata), Austral Bracken (Pteridium esculentum), Grey Tussock-grass (Poa sieberiana) and Tasman Flax-lily (Dianella tasmanica).

Montane Damp Forest

The more protected mountain slopes support a tall forest up to 40m in height, dominated in its lower altitudinal range by Mountain Grey Gum (Eucalyptus cypellocarpa), Messmate (Eucalyptus obliqua), Narrow-leaf Peppermint (Eucalyptus radiata) and occasionally Manna Gum (Eucalyptus viminalis). At higher altitudes, Montane Damp Forest is often dominated by pure stands of Alpine Ash (Eucalyptus delegatensis). Montane Damp Forest is closely related to Damp Sclerophyll Forest, with which it intergrades between 800 and 1000 m in elevation.

Montane Damp Forest features a open to rather dense layer of tall shrubs, amongst which Silver Wattle (Acacia dealbata), Blackwood (Acacia melanoxylon), Mountain Hickory Wattle (Acacia obliquinervia), Elderberry Panax (Polyscias sambucifolia), Blunt-leaf Bitter-pea (Daviesia laxiflora) and Rough Coprosma (Coprosma hirtella) are prominent.

The ground layer is characterised by grasses and herbs, including Bidgee-widgee (Acaena novae-zelandiae), Sword Tussock-grass (Poa ensiformis), Mountain Cotula (Leptinella filicula), Derwent Speedwell (Parahebe derwentiana), Common Lagenifera (Lagenifera stipitata) and Ivy-leaf Violet (Viola hederacea). Mother Shield-fern (Polystichum proliferum) is common in moister sites.

Montane Wet Forest

Montane Wet Forest occupies the most protected, usually south-facing slopes and gullies. Here soils are deep, fertile and well-drained. The canopy may grow to more than 60 m, and consists of pure or mixed stands of Alpine Ash (Eucalyptus delegatensis), and Shining Gum (Eucalyptus nitens).

Manna Gum (Eucalyptus viminalis) may be a co-dominant in the Blue and Royston Ranges, while significant occurrences of Tingaringy Gum (Eucalyptus glaucescens) and Errinundra Shining Gum (Eucalyptus denticulata) are recorded from Montane Wet Forest on the Baw Baw Plateau.

The tall second storey of Montane Wet Forest commonly includes Myrtle Beech (Nothofagus cunninghamii) and Forest Wattle (Acacia frigescens), which grow above a dense layer of Soft Tree-ferns (Dicksonia antarctica). At ground level, Hard Water-fern (Blechnum wattsii), Bat's-wing Fern (Histiopteris incisa) and Mother Shield-fern (Polystichum proliferum) are characteristic of this community.

Although this community is closely related to Wet forest, the floristic distinction lies in the substitution of most of the characteristic shrubs and trees. Notably absent in Montane Wet Forest are broad-leafed shrubs such as Hazel Pomaderris (Pomaderris aspera), Blanket-leaf (Bedfordia arborescens), Musk Daisy-bush (Olearia argophylla), Austral Mulberry (Hedycarya angustifolia), and Tree Lomatia (Lomatia fraseri), and the Rough Tree-fern (Cyathea australis).

On the north-eastern face of the Baw Baw massif, Mountain Ash (Eucalyptus regnans) ascends to approximately 1200 m in association with species characteristic of both Montane Wet Forest and Wet forest (see below). This unusually high-elevation occurrence may be a response to the tempering effect of the massif on the prevailing south-westerly winds, or to soil temperature variation due to insolation.

The presence of Myrtle Beech in the second storey reflects the strong association between Montane Wet Forest and Cool Temperate Rainforest. In protected sites, especially following a long fire-free period, stands of Myrtle Beech may achieve a degree of canopy closure sufficient for them to be considered Cool Temperate Rainforest, despite the presence of emergent eucalypts.

Montane Riparian Thicket

Dense thickets of Mountain Tea-tree (Leptospermum grandifolium) occur along drainage lines in montane and sub-alpine areas. Montane Riparian Thicket is associated with a number of other ecological vegetation classes, often arising at the outlets of sub-alpine heathlands, and descending to intergrade with Cool Temperate Rainforest or Riparian Thicket at lower altitudes.

The canopy of Montane Riparian Thicket may vary in height up to approximately 15m. Cool Temperate Rainforest dominants Myrtle Beech (Nothofagus cunninghamii) and Sassafras (Atherosperma moschatum) are frequently sub-dominant in this community.

Soils are similar to the often sodden, peaty soils of the Wet Sub-alpine Heathland. A thick substrate of Sphagnum is often present. The ground layer flora includes Alpine Water-fern (Blechnum penna-marina), Tall Sedge (Carex appressa), Forest Sedge (Carex alsophila), Pretty Grass-flag (Libertia pulchella) and Hard Water-fern (Blechnum wattsii). The Baw Baw Berry (Wittsteinia vacciniacea), although considered rare in Victoria (Gullan et al 1990), is frequently encountered as a low shrub within this community. It is endemic in the Victorian Central Highlands.

An unusual variant of this community occurs at Bellel Creek, south-east of Marysville, and at the Xylophone Bridge on the Murrindindi River. Here, Mountain Tea-tree is locally absent, but the ferns, herbs and sedges of the understorey remain to produce curious open bogs. The events or environmental factors leading to the establishment of such vegetation are unclear, although such sites frequently occur immediately upstream of the confluence of two streams.

Cool Temperate Rainforest

Cool Temperate Rainforest occurs in protected gully heads, on surrounding slopes and along streams throughout the wetter, mountainous parts of the Study Area. Moisture and the virtual absence of fire are the key determinants of its distribution.

Cool Temperate Rainforest is dominated by Myrtle Beech (Nothofagus cunninghamii) and Southern Sassafras (Atherosperma moschatum) which typically form a more or less continuous, dense canopy up to 40 m in height. Scattered emergent eucalypts may be present. Blackwood (Acacia melanoxylon) may form part of the closed rainforest canopy in some stands, but it is also widespread in other ecological vegetation classes.

The understorey features an array of ferns, including Soft Tree-fern (Dicksonia antarctica), Hard Water-fern (Blechnum wattsii) and Mother Shield-fern (Polystichum proliferum). The moist, sheltered conditions allow an number of epiphytic fern species to flourish, including Kangaroo-fern (Microsorum diversifolium), Filmy Ferns (Hymenophyllum spp.) and Long Fork-fern (Tmesipteris billardieri). Mosses and liverworts are abundant.

Several rare species occur in some Cool Temperate Rainforest stands in the upper Bunyip River catchment, notably Tall Astelia (Astelia australiana), Oval Fork-fern (Tmesipteris ovata), and Bristly Shield-fern (Lastreopsis hispida).

Wet Forest

Wet Forest is usually dominated by Mountain Ash (Eucalyptus regnans), forming the tallest forests in the study area. Occurring on the protected slopes of the ranges, plateaus and outlying hills, these sites tend to have abundant rainfall, deep, rich, well-drained soils, and offer some degree of fire protection.

The canopy may grow to 80 m in height. Beneath it, a second storey of trees including Silver Wattle (Acacia dealbata) and Blackwood (Acacia melanoxylon) may reach 35 m. The third storey comprises broad-leafed shrubs such as Hazel Pomaderris (Pomaderris aspera), Blanket-leaf (Bedfordia arborescens), Musk Daisy-bush (Olearia argophylla), Austral Mulberry (Hedycarya angustifolia), Tree Lomatia (Lomatia fraseri) and Banyalla (Pittosporum bicolor) grow to 20 m in height.

A dense layer of Soft Tree-fern (Dicksonia antarctica) and Rough Tree-fern (Cyathea australis) to 5m is characteristic. The moist, shaded ground layer supports Mother Shield-fern (Polystichum proliferum), Hard Water-fern (Blechnum wattsii), Shade Nettle (Australina pusilla) and White Elderberry (Sambucus gaudichaudii). In the wettest fern-gullies, Shiny Shield-fern (Lastreopsis acuminata) and Mother Spleenwort (Asplenium bulbiferum) are common.

Of particular note are the extensive areas in the Central Highlands where two extreme fires in succession (1926 and 1939) have led to the development of thickets, usually of Silver Wattle (Acacia dealbata) or Blackwood (Acacia melanoxylon), without a eucalypt overstorey. The interval between these fires was insufficient to allow eucalypt seed stores to be replenished.

While extremely severe and widespread fires such as Black Friday, 1939, and Ash Wednesday, 1983, may completely raze vast areas of forest, other less severe fires can produce a variety of localised effects which result in the development of mixed-age stands of Mountain Ash (Eucalyptus regnans). Although not extensive, these stands do occur in, for example, several of the Melbourne Water Catchment Areas.

Many Wet Forest species may also occur in stands which are transitional between this community and Cool Temperate Rainforest, having a consistent, dense understorey of Myrtle Beech (Nothofagus cunninghamii). This tends to occur in forests at the upper limit of elevation for this community, usually 700 - 1000 m. The transition to rainforest will continue only in the absence of fire or other major disturbance.

The following rare species are associated with Wet Forest in the Study Area: Butterfly Orchid (Sarcochilus australis) and Gully Grevillea (Grevillea barklyana) in the Bunyip River area, and Shiny Phebalium (Phebalium wilsonii) in the O'Shannassy Catchment.

Damp Forest

Damp Forest is a widespread ecological vegetation class occupying a range of sites on a variety of soils and aspects. It occurs from 200 to 1000 m in elevation. It differs from Wet forest in that it has a simpler structure without a distinct tree-fern layer, that characteristic shrubs usually have smaller, tougher leaves, and that the ground layer is much drier, supporting more herbs and grasses.

Messmate (Eucalyptus obliqua) and Mountain Grey Gum (Eucalyptus cypellocarpa) are the characteristic dominants in the overstorey, although Mountain Ash, Manna Gum, Silver-top (Eucalyptus sieberi) and Eurabbie (Eucalyptus globulus ssp. bicostata) may be locally dominant.

The species comprising the shrub layer of Damp Forest vary across the study area, although the following are widespread: Hazel Pomaderris (Pomaderris aspera), Prickly Coprosma (Coprosma quadrifida), Bootlace Bush (Pimelea axiflora), Prickly Moses (Acacia verticillata) and Snow Daisy-bush (Olearia lirata).

The ground layer is similarly variable across the study area, but characteristic species include Common Ground-fern (Calochlaena dubia), Ivy-leaf Violet (Viola hederacea), Rough Tree-fern (Cyathea australis), Mountain Clematis (Clematis aristata), Cinquefoil (Geranium potentilloides) and Tall Sword-sedge (Lepidosperma elatius).

Riparian Thicket

Dense thickets of Woolly Tea-tree (Leptospermum lanigerum) and/or Scented Paperbark (Melaleuca squarrosa) occur on broad beds of small streams or on the regularly flooded terraces of large streams and rivers. Soils are usually sandy or gravelly, but with high silt levels.

Woolly Tea-tree occurs throughout the study area, while Scented Paperbark is confined to areas south of the Divide.

The ground layer is usually dominated by tufts of Fishbone Water-fern (Blechnum nudum), in association with Soft Tree-fern, Red-fruit Saw-sedge (Gahnia sieberiana), Sedges (Carex spp.) and Spreading Fan-fern (Sticherus lobatus). One population of Tall Astelia (Astelia australiana) occurs within this community along the middle branch of Pioneer Creek, in the upper reaches of the La Trobe River. This species is considered vulnerable by Gullan et al (1990). It normally occurs in Cool Temperate Rainforest.

Riparian Thicket is structurally very similar to Montane Riparian Thicket, differing mainly in the floristic composition of the understorey. It frequently intergrades with Cool Temperate Rainforest, and Myrtle Beech (Nothofagus cunninghamii) often occurs as a sub-dominant species.

These three communities appear to occur along an environmental gradient, with Cool Temperate Rainforest occurring on the better-drained, fire-protected sites which are associated with the steeper slopes and deeper gullies, while Montane Riparian Thicket occurs in the high-altitude, peaty drainage lines. Riparian Thicket is found on the lower elevation stream banks and terraces. However, little data is available to explain fully the relationship between these communities; the explanation above is based on anecdotal evidence.

Riparian Forest

Riparian Forest is a tall forest of river banks and alluvial terraces. It tends to occur along quite swift-flowing streams. It is normally dominated by Manna Gum (Eucalyptus viminalis), with Silver Wattle (Acacia dealbata), Blackwood (Acacia melanoxylon), Hazel Pomaderris (Pomaderris aspera), Victorian Christmas-bush (Prostanthera lasianthos) and Prickly Coprosma (Coprosma quadrifida) in the shrub layer.

An abundance of moisture combined with fertile, well-drained soils explains the strong floristic links with Wet forest. The richness of the understorey of Riparian Forest is noteworthy, with a wide variety of terrestrial species as well as a suite of semi-aquatic plants. Usually present are Fishbone Water-fern (Blechnum nudum), Tall Sedge (Carex appressa), Mother Shield-fern (Polystichum proliferum), Swamp Club-sedge (Isolepis inundata), Small-leaf Bramble (Rubus parvifolius) and Soft Tree-fern (Dicksonia antarctica).

Environmental weeds are a common component of Riparian Forest. This is due to a variety of factors, including the natural pattern of disturbance through flooding, the amenable environment, and the history of human activity along rivers.

A major variant of Riparian Forest occurs on saturated river flats, sometimes adjacent to a swiftly-flowing river. These sites are regularly flooded. Soils are silt-rich river sands and gravels in this situation, although sites with heavier clay soils may also support this variant. It is usually dominated by Swamp Gum (Eucalyptus ovata), although Mealy Stringybark (Eucalyptus cephalocarpa) and Messmate (Eucalyptus obliqua) may also be present, particularly in the La Trobe, Bunyip and Tarago River catchments.

The second storey includes Blackwood (Acacia melanoxylon), Woolly Tea-tree (Leptospermum lanigerum), Hazel Pomaderris (Pomaderris aspera) and, south of the Great Dividing Range, Scented Paperbark (Melaleuca squarrosa).

In the ground layer, Soft Tree-fern (Dicksonia antarctica), Red-fruit Saw-sedge (Gahnia sieberiana), Water-ferns (Blechnum spp.), Tall Sword-sedge (Lepidosperma elatius), Common Reed (Phragmites australis), and Brooklime (Gratiola peruviana) are common. Showy Willow-herb (Epilobium pallidiflorum), which is considered to be depleted, may be present if the area is not grazed.

This variant of Riparian Forest has strong affinities with Riparian Thicket, Riparian Forest, and Swamp Heath.

Examples include the stand of Buxton Gum (Eucalyptus crenulata) on river flats beside the Acheron River south of Buxton, where the atypical understorey combines elements of Wet Heathland and Floodplain Wetland Complex, as well as many of the usual species listed above.

Herb-rich Foothill Forest

Herb-rich Foothill Forest occurs mainly in the northern part of the Study Area. The canopy is usually 20 to 35 m tall, and is made up of Narrow-leaf Peppermint (Eucalyptus radiata) and Messmate (Eucalyptus obliqua) in the Big River, Black Range and Mt Disappointment areas, while Eurabbie (Eucalyptus globulus ssp. bicostata), Manna Gum (Eucalyptus viminalis) and Candlebark (Eucalyptus rubida) are more common in the Strathbogie Ranges, Tallarook State Forest and around Lake Eildon.

The sparse low shrub layer consists normally of two species: Common Cassinia (Cassinia aculeata) and Silver Wattle (Acacia dealbata).

The ground layer is dense and species rich. The following species are frequently present: Kidney-weed (Dichondra repens), Weeping Grass (Microlaena stipoides), Common Lagenifera (Lagenifera stipitata), Bidgee-widgee (Acaena novae-zelandiae), Cinquefoil (Geranium potentilloides), Ivy-leaf Violet (Viola hederacea), Grey Tussock-grass (Poa sieberiana), Soft Tussock-grass (Poa morrisii), Austral Bear's-ears (Cymbonotus preissianus) and Prickly Woodruff (Asperula scoparia).

Austral Bracken (Pteridium esculentum) is usually present, and may tend to dominate the ground layer if frequent disturbance, particularly by fire, occurs.

Shrubby Foothill Forest

Similar in structure to Herb-rich Foothill Forest, Shrubby Foothill Forest has a more dense and varied shrub layer, but tends to lack a diverse ground layer. It is widespread on higher slopes, particularly between 400 and 900 m in elevation, both north and south of the Great Dividing Range.

The dominant trees are Messmate and Narrow-leaf Peppermint, although Silver-top (Eucalyptus sieberi), Mountain Grey Gum (Eucalyptus cypellocarpa) and Scent-bark (Eucalyptus ignorabilis) may occur in this community in the Walhalla area.

A wide variety of shrubs characterise this community across its range. Common among these are Narrow-leaf Wattle (Acacia mucronata), Dusty Miller (Spyridium parvifolium), Handsome Flat-pea (Platylobium formosum), Prickly Bush-pea (Pultenaea juniperina), Rough Bush-pea (Pultenaea scabra), Varnish Wattle (Acacia verniciflua), Common Cassinia (Cassinia aculeata), Shiny Cassinia (Cassinia longifolia), Hop Goodenia (Goodenia ovata) and Pink-bells (Tetratheca ciliata).

The ground layer includes Ivy-leaf Violet, Common Raspwort (Gonocarpus tetragynus) and Grey Tussock-grass. Forest Wire-grass (Tetrarrhena juncea) and Austral Bracken (Pteridium esculentum) are commonly present, and sometimes dominant.

Lowland Forest

Lowland Forest is closely related to the two previous communities, although it tends to occur at lower elevations, on yellowish gradational soils and leached sands of low fertility. Examples are found mainly on the lower slopes in the La Trobe, Bunyip and Tarago catchments. It differs in having an understorey with strong floristic affinities with heathy woodlands and heathlands. The understorey

The canopy includes Silver-top, Yertchuk (Eucalyptus consideniana), and Messmate. Occasionally, White Stringybark (Eucalyptus globoidea) and Brown Stringybark (Eucalyptus baxteri) are present.

The density and species composition of the shrub layer is quite variable, but normally includes Prickly Tea-tree (Leptospermum continentale), Golden Bush-pea (Pultenaea gunnii), Wiry Bauera (Bauera rubioides), Bushy Hakea (Hakea sericea), Common Heath (Epacris impressa) and Broom Spurge (Amperea xiphoclada). Patches of Hairpin Banksia (Banksia spinulosa) are common.

The ground layer features Forest Wire-grass, Austral Bracken, Thatch Saw-sedge (Gahnia radula), Blue Dampiera (Dampiera stricta), Small Grass-tree (Xanthorrhoea minor) and Trailing Goodenia (Goodenia lanata).

Lowland Forest frequently occurs in conjunction with Heathy Woodland, Wet Heathland and Swamp Heathland (see below).

Valley Grassy Forest

Valley Grassy Forest is restricted to the lower slopes and valleys of the foothill country to the north-east of Melbourne, usually on acidic duplex soils and on southerly aspects. It is closely related floristically to Grassy Dry Forest and Herb-rich Foothill Forest

The overstorey is dominated by a mixture of Red Box (Eucalyptus polyanthemos), Red Stringybark (Eucalyptus macrorhyncha), Long-leaf Box (Eucalyptus goniocalyx) and Yellow Box (Eucalyptus melliodora). In low lying sites, often adjacent to seasonally inundated areas, Swamp Gum (Eucalyptus ovata) may be present.

The shrub layer tends to be rather sparse, often comprising a scattering of Burgan (Kunzea ericoides), Cherry Ballart (Exocarpos cupressiformis), Black Wattle (Acacia mearnsii), Sweet Bursaria (Bursaria spinosa) and Common Cassinia (Cassinia aculeata). Sweet Pittosporum (Pittosporum undulatum), although possibly indigenous to the Study Area, is an invasive environmental weed in this community. Also commonly present as a weed is Monterey Pine (Pinus radiata).

A rich array of native grasses and herbs occur in the low ground layer. Weeping Grass (Microlaena stipoides), Kangaroo Grass (Themeda triandra), Grey Tussock-grass (Poa sieberiana), and Silver-top Wallaby-grass (Chionochloa pallida) are common, in association with Kidney-weed (Dichondra repens), Common Maidenhair (Adiantum aethiopicum) and Ivy-leaf Violet (Viola hederacea).

Heathy Dry Forest

There are three focuses for Heathy Dry Forest in the Study Area: the Kinglake area, upper Goulburn Valley and upper Thomson Valley. In most areas, it tends to occur on shallow stony soils of low fertility, with poor water retention capabilities. However, some sites in the Kinglake area appear to occur on the margins of acidic duplex soils, which may explain some floristic differences in these sites.

Generally, Heathy Dry Forest is dominated by a low canopy of Broad-leaf Peppermint (Eucalyptus dives). In the Kinglake area, Messmate (Eucalyptus obliqua), Long-leaf Box (Eucalyptus goniocalyx) and Mealy Stringybark (Eucalyptus cephalocarpa) may also be present. In the upper Thomson Valley, stunted Mountain Grey Gum (Eucalyptus cypellocarpa), Silver-top (Eucalyptus sieberi) and Yertchuk (Eucalyptus consideniana) may occur. In the upper Goulburn Valley, Broad-leaf Peppermint (Eucalyptus dives) often occurs at higher elevations with Candlebark (Eucalyptus rubida), indicating the close links between this community and Montane Dry Woodland. In fact, these two communities may intergrade for considerable distances on northerly slopes.

The understorey of Heathy Dry Forest features a number of species of the Australian heath family, the Epacridaceae, including Prickly Broom-heath (Monotoca scoparia), Common Heath (Epacris impressa), Daphne Heath (Brachyloma daphnoides) and Common Beard-heath (Leucopogon virgatus).

In the Kinglake area, other understorey species include Rosy Baeckea (Baeckea ramosissima), Wire Rapier-sedge (Lepidosperma semiteres), Austral Grass-tree (Xanthorrhoea australis), the rare Creeping Grevillea (Grevillea repens), Cat's Claws Grevillea (Grevillea alpina), Silver Banksia (Banksia marginata) and Bushy Hakea (Hakea sericea).

In the upper Goulburn and Thomson Valleys, common species, in addition to the heaths mentioned above, include Narrow-leaf Bitter-pea (Daviesia leptophylla), Gorse Bitter-pea (Daviesia ulicifolia) and Narrow-leaf Wattle (Acacia mucronata). These legumes respond vigorously following fire, regenerating either from seed or by re-sprouting from roots and butts. There is a likelihood that frequent fires in Heathy Dry Forest will lead to these species becoming dominant at the expense of the heaths.

Other common understorey species in the upper Goulburn and upper Thomson Valleys are Cluster-flower Geebung, (Persoonia confertiflora), Dwarf Geebung (Persoonia chamaepeuce), Heath Milkwort (Comesperma ericinum), and Common Hovea (Hovea linearis).

Throughout the range of Heathy Dry Forest, Silvertop Wallaby-grass (Chionochloa pallida) is a common, often dominant, member of the ground layer. Its dominance at some sites may reflect that the site has remained unburnt for a long period.

It is clear that fire regimes are of great importance to the understorey species composition of this community.

A number of ecological vegetation classes are closely allied to Heathy Dry Forest. Stands of vegetation which are intermediate between this and Grassy dry forest are common.

The Coranderrk Aqueduct south of Healesville winds through vegetation which is intermediate between Heathy Dry Forest and Heathy Woodland (see below).

Grassy Dry Forest

This community occurs on relatively exposed aspects, often on moderately fertile acidic duplex soils. Grassy Dry Forest is best developed in the hills to the north-east of Melbourne and in the foothills of the Goulburn Valley between Jamieson and Seymour.

It is dominated by the same suite of eucalypts as Valley Grassy Forest, with which it is often associated. These are Red Box (Eucalyptus polyanthemos), Red Stringybark (Eucalyptus macrorhyncha), Long-leaf Box (Eucalyptus goniocalyx) and Yellow Box (Eucalyptus melliodora).

The understorey is open, grassy and rich in species. Commonly present are Grey Tussock-grass (Poa sieberiana), Silvertop Wallaby-grass (Chionochloa pallida), Velvet Wallaby-grass (Danthonia pilosa), Plume-grasses (Dichelachne spp.), Grey Guinea-flower (Hibbertia obtusifolia), Purple Coral-pea (Hardenbergia violacea), Stinking Pennywort (Hydrocotyle laxiflora), Blue Pincushion (Brunonia australis), Green Rock-fern (Cheilanthes austrotenuifolia), Cotton Fireweed (Senecio quadridentatus) and Common Raspwort (Gonocarpus tetragynus).

An unusual feature of some stands of Grassy Dry Forest are the dense thickets of Burgan (Kunzea ericoides). These may form following a particular sequence of fire events, and, once, established, prevent the previously dominant eucalypts from regenerating. They are frequently associated with a rich orchid flora. Good examples occur in the Cathedral Range State Park.

Burgan thickets may also occur with a suite of understorey species common to Valley Grassy Forest, especially in riparian or rocky gorge situations.

Grassy Dry Forest is prone to invasion by a wide range of environmental weeds, particularly herbs and grasses. Fire frequency is likely to be quite high at sites supporting this community. If unburnt for long periods (25+ years), tussock grasses tend to predominate.

Rocky Outcrop Shrubland

Rocky outcrops are frequently of botanical interest because they contain a range of unusual micro-habitats, from highly exposed rock-faces, to damp, sheltered crevices.

Rather than being a discrete ecological vegetation class, Rocky Outcrop Shrubland commonly includes a number of rock-adapted species, with a suite of species from the surrounding vegetation which can tolerate the rocky outcrop environment.

For this reason, it is pertinent to discuss the vegetation of a number of prominent rocky outcrops in the Study Area separately. This is not a complete list.

Seven Acre Rock and Ben Cairn

These extensive granite outcrops support scattered Mountain Grey Gum (Eucalyptus cypellocarpa) and Silver-top (Eucalyptus sieberi) with Lemon Bottlebrush (Callistemon pallidus) and Long-leaf Wax-flower (Eriostemon myoporoides).
The Cathedral

The steeply uplifted sedimentary rock which forms the Cathedral Range supports vegetation with affinities to the surrounding Grassy dry forest. Stunted Red Stringybark, Broad-leaf Peppermint and, rarely, Snow Gum, occur along the crest. Common shrubs include Round-leaf Mint-bush (Prostanthera rotundifolia), Fairy Wax-flower (Eriostemon verrucosus) and Lemon Bottlebrush (Callistemon pallidus). The ground layer includes a wide range of grasses and herbs characteristic of dry forests.
Murchison - Strath Creek Falls

The broad, exposed rocky hillside to the east of Murchison Falls supports a sparse shrubland of Black Wattle (Acacia mearnsii), Clustered Everlasting (Helichrysum semipapposum), Kangaroo Grass (Themeda triandra) and a variety of herbs of dry sites.
Outcrops of Strathbogie Granite, Yea-Seymour area

Outcrops of granite occur quite frequently along the slopes above the Goulburn River in the Yea-Seymour area. On protected sites, these outcrops carry a dense, low moss-bed or herbfield, which may be very species rich. These have been inadequately sampled, but are nevertheless noteworthy.

Box Woodland

Box Woodland is an open, grassy woodland dominated by Grey Box (Eucalyptus microcarpa). Within the Study Area, it is restricted to the lower slopes and upper terraces of the Goulburn River. In the Alexandra area, the best examples can be seen along road reserves. The relatively fertile soils of these areas has led to a dramatic reduction in the extent of Box Woodland through clearing for agriculture, both in the Study Area, and throughout its range in Victoria.

A variant of this community which includes White Box (Eucalyptus albens), Red Box (Eucalyptus polyanthemos) and Yellow Box (Eucalyptus melliodora) occurs sporadically along the Goulburn Valley from the Merton area to Trawool. This variant has affinities with Grassy Dry Forest, and is reminiscent of dry forests of north-eastern Victoria..

The understorey of Box Woodland is dominated by Wallaby-grasses (Danthonia spp.) and Spear-grasses (Stipa spp.), with a scattering of Hedge Wattle (Acacia paradoxa).

Due to the fertility of the soils, a history of grazing and proximity to agricultural land, stands of Box Woodland usually contain a suite of introduced grasses, herbs and woody shrubs.

Plains Grassy Woodland

The most common components of this community are the River Red Gum (Eucalyptus camaldulensis) dominated grassy woodlands, occurring on seasonally water-logged clays and clay-loams.

These soils may be alluvial, or derived either from sedimentary rock or basalt. Plains Grassy Woodland may occur on lower slopes or swampy river flats, from Cardinia Creek in the south-east, to the Goulburn Valley in the north and the basalt plains around Wallan in the west.

A curious variant occurs in the Yan Yean catchment, where Candlebark (Eucalyptus rubida) and Snow Gum (Eucalyptus pauciflora [lowland ecotype]) dominate a characteristic understorey.

Plains Grassland

Dominated by Kangaroo Grass (Themeda triandra), Plains Grassland is a tussock grassland with a scattered and much depleted distribution, mostly on fertile, basalt-derived soils. It once occurred from Melbourne in the east to the Hamilton district in far south-western Victoria, but has largely been cleared or grossly modified for agriculture.

In addition to Kangaroo Grass, characteristic species include Pink Bindweed (Convolvulus erubescens), Common Bog-sedge (Schoenus apogon), Lemon Beauty-heads (Calocephalus citreus), Sheep's Burr (Acaena echinata) and Common Wallaby-grass (Danthonia caespitosa). A wide variety of environmental weeds, mainly grasses and herbs, are a feature of the remnants of this community.

It is important to note that Kangaroo Grass is widespread, being a character species of several other ecological vegetation classes. It should therefore not be assumed that all patches of Kangaroo Grass constitute Plains Grassland.

Plains Grassland is restricted in the Study Area to isolated occurrences, mainly on private land in the Somerton area, on the outskirts of metropolitan Melbourne. It occurs on public land at Epping Cemetery.

Floodplain Riparian Woodland

This community comprises the woodland vegetation which typically occurs along the banks of the larger, slower-moving rivers of the Study Area, including the Goulburn, Yea, Acheron, and Yarra River. It frequently occurs in conjunction with one or more floodplain wetland communities.

River Red Gum (Eucalyptus camadulensis) forms a tall, woodland canopy over a medium to tall shrub layer including Silver Wattle (Acacia dealbata), Tree Violet (Hymenanthera dentata), River Bottlebrush (Callistemon sieberi) and River Tea-tree (Leptospermum obovatum). The ground layer features Common Tussock-grass (Poa labillardieri) on the drier, elevated banks, with Club-sedges (Isolepis spp.), Rushes (Juncus spp.), Common Reed (Phragmites australis) and Water-ribbons (Triglochin procera) occupying the saturated or inundated soils at the water's edge.

Environmental weeds form a major component of this community in virtually all stands. Willows (Salix spp.) and a wide variety of pasture grasses are ubiquitous.

Grassy Wetland

Grassy Wetland occurs on small, seasonally-flooded depressions on fertile, basalt-derived soils, often as scattered patches amongst Plains Grassland. The dominant species include Veined Swamp Wallaby-grass (Amphibromus nervosus), Brown-back Wallaby-grass (Danthonia duttoniana), Common Spike-sedge (Eleocharis acuta), Small Spike-sedge (Eleocharis pusilla), Common Tussock-grass (Poa labillardieri) and Australian Sweet-grass (Glyceria australis).

In the Study Area, this community is restricted to private land and rail reserves in the Wallan district, in the head-waters of the Merri and Darebin Creek catchments.

Wetland Complex

Deep, permanent billabong

Deep, permanent billabongs occur along the floodplains of the Yarra and Goulburn Rivers. Typically, these billabongs have a dense fringe of vegetation, but, due to the greater depth of water in the centre, tend to include open water. This open water may support a carpet of Duckweed (Lemna spp.) and/or Azolla (Azolla spp.).

The fringing vegetation includes Tall Spike-sedge (Eleocharis sphacelata), Milfoils (Myriophyllum spp.), Water-ribbons (Triglochin procera), Cumbungi (Typha orientalis), Common Reed (Phragmites australis) and Rushes (Juncus spp.).

Shallow, seasonal billabong

Shallower billabongs which dry out in summer commonly support a herbfield including Common Spike-sedge (Eleocharis acuta), Slender Knot-weed (Persicaria decipiens), Lesser Joyweed (Alternanthera denticulata), Common Blown-grass (Agrostis avenacea) and Sneezeweeds (Centipeda spp.).

These billabongs may dry out due to the poorer water holding capabilities of the clay substrate, or the lack of recharge. Within the Study Area, such billabongs occur along the Yarra and Goulburn Rivers.

Floodplain wet flat

Floodplain wet flats occur on river flats where seepage or overflow is retained by the river-side levee banks. Characteristic vegetation includes Common Reed (Phragmites australis), Marsh Club-sedge (Bolboschoenus medianus), Tassel Sedge (Carex fascicularis), Tall Sedge (Carex appressa), Large Bindweed (Calystegia sepium) and Common Tussock-grass (Poa labillardieri).

Heathy Woodland

Heathy Woodland occurs on gentle, north-facing, lower slopes in the Gembrook, Tonimbuk, Tanjil and Moondarra areas. Soils are commonly sandy at the surface, with a clay or coffee-rock impeding layer at some depth. They may be seasonally wet, but dry out in the summer.

A low woodland of Narrow-leaf Peppermint (Eucalyptus radiata), Mealy Stringybark (Eucalyptus cephalocarpa), Messmate (Eucalyptus obliqua), and/or Yertchuk (Eucalyptus consideniana) occurs over a shrub layer including Hairpin Banksia (Banksia spinulosa), Bushy Hakea (Hakea sericea), Furze Hakea (Hakea ulicina), Dagger Hakea (Hakea teretifolia), Prickly Tea-tree (Leptospermum continentale) and Common Heath (Epacris impressa).

The ground layer includes a number of grass species: Wiry Spear-grass (Stipa muelleri), Kangaroo Grass (Themeda triandra) and Reed Bent-grass (Deyeuxia quadriseta). Other ground layer species include Thatch Saw-sedge (Gahnia radula), Common Raspwort (Gonocarpus tetragynus) and Wattle Mat-lily (Lomandra filiformis). Small Grass-tree (Xanthorrhoea minor) is also commonly present.

Similarly, the absence of species of Hakea in some stands contrasts with their virtual dominance in others. These species, which rely on seed germination for post-fire regeneration, may be suppressed by frequent, low-intensity fires, which favour species which re-sprout from rhizomes (eg. Wiry Spear-grass, Thatch Saw-sedge).

Wet Heathland

Wet Heathland normally occurs in depressions or on lower slopes where soils are saturated for considerable periods of the year. This may be due to the impeding layer in the soil being much closer to the soil surface than is the case for Heathy Woodland. Species characteristic of this community are therefore those which can tolerate saturated soils.

Mealy Stringybark forms a stunted, scattered canopy in some stands, but is absent from others. Scented Paperbark (Melaleuca squarrosa), Yellow Hakea (Hakea nodosa), Prickly Tea-tree and Pink Swamp-heath (Sprengelia incarnata) form a dense shrub layer. In the ground layer, Spreading Rope-rush (Empodisma minus), Hair-sedge (Tetraria capillaris), Square Twig-sedge (Baumea tetragona), Pouched Coral-fern (Gleichenia dicarpa) and Swamp Selaginella (Selaginella uliginosa) are prominent.

Wet Heathland occurs in the Bunyip, Hill End, Mt Tanjil and Moondarra areas.

Swamp Heathland

Swamp Heathland is a tall heathland dominated by Scented Paperbark (Melaleuca squarrosa). It occurs on drainage lines of deep, saturated siliceous sands, and frequently occurs with the outlets of Wet Heathland areas.

Other characteristic species include Rosemary Everlasting (Helichrysum rosmarinifolium), Red-fruit Saw-sedge (Gahnia sieberiana), Soft Water-fern (Blechnum minus), Coral-ferns (Gleichenia spp.), Centella (Centella cordifolia), Tassel Cord-rush (Restio tetraphyllus) and Running Marsh-flower (Villarsia reniformis).

There are significant floristic and structural affinities between Swamp Heathland and low elevation occurrences of Riparian Thicket, but, in general, the former has a much denser, sedge and rush-dominated groundlayer, the latter being more ferny..

The environmental differences which segregate stands of Swamp Paperbark dominated Swamp Scrub and Scented Paperbark dominated Swamp Heathland centre on soils, with the former tending towards heavy clays, while the latter occurs on sands or sandy clays.

Swamp Heathland occurs in the Bunyip, Tonimbuk, Tanjil, Woori Yallock and Moondarra areas.

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