The following EVC descriptions are either from the work of Doug Frood and Biosis Research Pty. Ltd. who undertook the Pre-1750s vegetation mapping for the Central Highlands, or, from the old-growth report for the adjacent North East Victoria study area, as indicated with an asterisk (*).
There were two grassland communities found in the study area pre-1750 and both have been listed under the Flora and Fauna Guarantee Act (1988). Western Basalt Plains Grassland on the fertile self-mulching clays derived from basalts under rainfall regimes of less than 600mm in the area between the west of the study area (south of the Great Divide) east to the Darebin Creek. It is at its eastern-most distribution in Victoria within the study area and was once much more extensive to the west on the western basalt plains. The overstorey was scattered, and if present, consisted of occasional River Red Gums Eucalyptus camaldulensis (in sites with poor drainage), Drooping Sheoke Allocasuarina verticillata, Lightwood Acacia implexa and tree-form Silver Banksia Banksia marginata. The ground layer was composed of a mosaic of grasses and forbs. The relative abundance of these life forms being dependant on the frequency and time since fire or other disturbance that could establish bare ground between the dense grass tussocks. The grasses and shrubs being favoured by infrequent fires with the forbs more abundant in more frequently or recently burnt or disturbed sites. The common grasses included: Kangaroo Grass Themeda triandra, ?Stipa, ?Poa. The forbs (daisies, lilies and orchids) are represented by a variety of genera and species including Bluebells Wahlenbergia spp., Chrysocephalum apiculatum, Craespedia spp. Lemon Beauty-heads Calocephalus citreus, Scaly Buttons Leptorhynchus squamatus, Bluebells Wahlenbergia spp., Blue Devil Eryngium ovinum, Pink Bindweed Convovulus erubescens.
South Gippsland Plains Grassland once occurred on the fertile silts and alluviums that also supported Swamp Scrub. Under frequent fire regimes it is believed that a disclimax community of grasses forbs and shrubs developed in place of the usually dense cover of Swamp Paperbark Melaleuca ericifolia which characterises Swamp Scrub. Very few examples now remain of this type of grassland with remnants being restricted to rail reserves and cemeteries largely outside the study area. The overstorey was scattered and only present where fire was less frequent or less intense consisting of Golden Spray Viminaria juncea, Blackwood Acacia melanoxylon and Drooping Sheoke Allocasuarina verticillata. The ground layer consists of a dense sward of graminoids including Common Tussock Grass Poa labillardieri, Mat Grass Hemarthria uncinata, Weeping Grass Microlaena stipoides and Blown Grasses Agrostis spp. various rushes Juncus spp. and Spiny-headed Wattle Mat-rush Lomandra longifolia var. longifolia. Forbs were not common in this community.
Grey Clay Drainage Line Complex
Three variants of this complex have been noted along the Merri Creek (NRE EcologicalSurvey Report 42). It occurs as brackish seasonal wetlands on ephemeral drainage lines on heavy basalt-derived grey clays of the Merri and Darebin Creeks. They are separated from Plains Grassy Wetlands (see below) by the presence of species indicative of salinity. These species include: Salt Pratia Pratia irrigata, Sea Celery Apium spp., Australian Lilaeopsis Lilaeopsis polyantha, Australian Salt-grass Distichlis distichophyllaand Shiny Swamp-mat Selliera radicans. Floristics vary with wetness, with Blown Grasses Agrostis spp., Salt Club-sedge Bolboschoenus caldwellii, Common Spike-sedge Eleocharis acuta, Common Tussock Grass Poa labillardieri, River Club-sedge Schoenplectus validus and locally common. The threatened Curly Sedge Carex tasmanica can be locally common in this vegetation.
Plains Grassy Wetland
These wetlands are shallow and non-saline and occur on volcanic tracts between the study area’s western boundary east to the Plenty River and generally occur in areas of Plains Grassy Woodland. This unit is not entirely analogous to the vegetation mapped in the Inner Melbourne LCC study due to the inclusion of other wetland types which included Saltmarshes, Cane-grass and Lignum Swamps. Within the context of the study area, much of the wetland occurs as a grassy sward with varying combinations of Brown-back Wallaby-grass Danthonia duttoniana, Veined Swamp Wallaby-grass Amphibromus nervosus, Austral Sweet-grass Glyceria australis, Common Spike-sedge Eleocharis acuta, and Common Tussock Grass Poa labillardieri. Rush-sedge Carex tereticaulis was probably more prevelant before settlement. Tangled Lignum Muelenbeckia florulenta and River Red gum Eucalyptus camaldulensis, if present, were mostly confined to the periphery of these wetlands. These habitats can be very rich in herbaceous species, at least in shallower sites. The more common of these includes Pricklefoot Eryngium vesiculosum, Poison Lobelia Lobelia pratioides, Upright Millfoil Myriophyllum crispatum, White Purslane Neopaxia australasica, Swamp Starwort Stellaria palustris and River Buttercup Ranunculus inundatus. A range of species (noteably the daisies Swamp Everlasting Bracteantha aff. subundulata, Pale Swamp Everlasting Helichrysum aff. rutidolepis (Lowland Swamps), Yam Daisy Microserisscapigera, Swamp Groundel Senecia psilocarpus, and Swamp Billy Buttons Craspedia paludicola) which appear to have once been major components of at least the outer zones of these wetlands, are now virtually extinct.
Swampy Riparian Complex
This complex consists of a number of floristic entities as mapped by Biosis Research and Doug Frood: Gully Woodland, Swamp Forest and Swampy Woodland. Their composition and ecology is poorly defined due to a lack of extant examples. Ecologically it is likely that some of these entities may once have been distinct at the EVC or the floristic community level. Until better characterisation can be obtained, they are for the present study considered as a complex.
Gully Woodland can be loosely characterised as the wetter end of Valley Grassy Forest which was associated with gully lines. Swamp Gum Eucalyptus ovata was usually present, the nearer this entity was to the adjacent riparian vegetation, with Mountain Swamp Gum Eucalyptus camphora or Yarra Gum Eucalyptus yarrensis also locally common. A smattering of other eucalypts may be represented depending on the adjacent EVC. Major associated species include Common Tussock Grass Poa labillardieri, Black Wattle Acacia mearnsii and Rushes Juncus spp., with a range of wet site species variously present such as Lanky Goodenia Goodenia elongata, Centella Centella cordifolia, Shining Buttercup Ranunculus glabrifolius, Creeping Brooklime Gratiola peruviana and Common Reed Phragmites australis. Ponds may be present, but the water courses (if defined) are never-the-less intermittent. Ferns may also be present including Rough Tree-fern Cyathea australis, Tender Brake Pteris tremula, Rasp Ferns Doodia spp. and Rainbow Fern Caloclaena dubia.
This vegetation was once common in the gullies associated with the Heidelberg, Plenty Yarrambat areas.
Swamp Forest is virtually extinct within the study area apart from a few examples on wet flats which are ecotonal with Swampy Woodland (see below) and small areas of Wet Forest riparian terraces which probably had similar floristics. This floristic entity represents the Wet to Damp Forest extension into swampy habitats associated with low gradient drainage lines and seepage slopes, primarily on rich volcanic soils around the Warragul-Drouin area. The major tree species appears to have been Strzelecki Gum Eucalyptus strzeleckii, with Swamp Gum Eucalyptus ovata in the ecologically marginal sites. A poorly known small-fruited form of Mountain Ash Eucalyptus regnans may have originally been more widespread in this floristic entity. Messmate Eucalyptus obliqua and Mountain Grey Gum Eucalyptus cypellocarpa my be present on more marginal sites. Other woody species included Muttonwood Rapanea howittiana, Blackwood Acacia melanoxylon and Scented Paperbark Melaleuca squarrosa. Whilst a number of Wet Forest shrubs may be present, they would have been at low levels and often restricted to perched positions on tree-fern trunks. The ground layer appears to have been primarily ferny to sedgy in character, including mixtures of wet forest and swamp species. Possibly the only intact remnant (of the upper reaches of a gully) had virtually a closed canopy of Soft Tree-fern Dicksonia antarctica over a bed of peat (quadrats F32077-8). The understorey has a number of Water Ferns Blechnum spp. sedges Carex spp. and a range of herbs. Tall Sword-sedge Lepidosperma elatius is prevelant on the marginal wet flat remnants. The low gradients were largely spring or seepage-fed, and historical anecdotes indicate they were swampy and lacked defined drainage lines.
Swampy Woodland has been coined for this floristic entity in the broad sense to cover a range of communities on wet flats and in drainage basins. As the vast majority of these habitats have been drained and cleared for agriculture, the original floristics are often obscured. Swamp Gum Eucalyptus ovata is usually present but is occasionally replaced by Mountain Swamp Gum Eucalyptus camphora or Yarra Gum Eucalyptus yarrensis. Messmate Eucalyptus obliqua, Narrow-leaved Peppermint Eucalyptus radiata, Manna Gum Eucalyptus viminalis, Green Scentbark Eucalyptus ignorabilis, and Mealy Stringybark Eucalyptus cephalocarpa can also be present, particularly on more marginal sites. Buxton Gum Eucalyptus crenulata is a very rare component.
In the southern part of the study area, Swamp Paperbark Melaleuca ericifolia was often a major constant in the vegetation. Some areas mapped as Swampy Woodland were presumably a mosaic of Swampy Woodland, Swamp Scrub and wetlands dominated by Common Reed Phragmites australis and herbaceous species, but the original patterns have been long-erased, and any attempts at reconstruction of these patterns would require detailed site inspection. Some areas would have approached Wet Heath or Riparian Forest in composition. Blackwood Acacia melanoxylon and Tree Everlasting Ozothamnus ferrugineus were frequent woody species. The ground layer varied from grassy-herbaceous through to heathy-shrubby with Myrtaceous genera such as Melaleuca and Leptospermum present. Common Tussock Grass Poa labillardieri would have been a widespread component. Ferns (Blechnum, and Dicksonia) would have been common in cooler areas.
While Swampy Woodland often occurs on stream terraces, between the stream levee and the adjacent slopes, there are many instances where there is no defined channel, or the vegetation occurs on broad-acre wet flats lacking streams.
Valley Heathy Forest
Geographically this EVC occurs in several widely dispersed localities in the study area south of the Great Divide. In the Moe area Lowland Forest grades into this grassy vegetation with a different suite of eucalypts that includes Eucalyptus ignorabilis, Candlebark Eucalyptus rubida, Manna Gum Eucalyptusviminalis, Yellow Box Eucalyptus melliodora and Narrow-leaved Peppermint Eucalyptus radiata. Swamp Gum Eucalyptus ovata can also extend upslope in this vegetation. The understorey consists of Wallaby Grasses Danthonia spp. and the ‘dry forest woodland species’ Tree Violet Hymemenathera dentata and Black Wattle Acacia mearnsii. Thatch Saw-sedge Gahnia radula and Prickly Ti-tree Leptospermum continentale appear to have been common, at least in the marginal sites. (L. continetale can be a component of grassy woodland on fertile Tertiary soils elsewhere in the State, with its relative abundance reflecting fire regimes. The distribution of this occurrence of Valley Heathy Forest appears to be mediated by both a rainshadow effect from the Strzlecki Ranges and the co-occurrence of Tertiary basalt-derived soils. Although the boundaries between Valley Heathy Forest and Lowland Forest can be difficult to define (given current clearing) the former is quite distinct from the latter.
In the Croyden-Bayswater area, the Yellow Box Eucalyptus melliodora-Candlebark Eucalyptus rubida association of Valley Grassy Forest is replaced by an open forest in which a wide range of other tree species may be present. These include: Mealy Stringybark Eucalyptus cephalocarpa, Messmate Eucalyptus obliqua, Narrow-leaved Peppermint Eucalyptus radiata, Long-leaf Box Eucalyptus goniocalyx, Yellow Box Eucalyptus melliodora and Manna Gum Eucalyptus viminalis. While this example is visually more sedgy than the area previously described with Thatch Saw-sedge Gahnia raduala and Small Grass-tree Xanthorrhoea minor, the grassy element is still present as are a range of ericoid shrubs. In this area both Kangaroo Grass Themeda triandra and Weeping Grass Microlaena stipoides are common. This vegetation once extended across the less dissected Silurian sedimentary terrain of the Blackburn-Mitcham and Box Hill north areas. North of this area where the soils are presumably younger, it is replaced by Grassy Dry Forest and Valley Grassy Forest. Valley Heathy Forest and Plains Grassy Woodland appear to have intergraded in the Box Hill-Balywyn area.
One small area of this vegetation occurs north of Mount Disappointment, and whilst a good floristic description is available, it may not be typical of Valley Heathy Forest elsewhere in the study area, as it may have affinities with Grassy Dry Forest and Box Ironbark Forest. It occurs on localised outwash from Silurian sandstone sedimentary ridges around Stony Creek. It is likely that the vegetation was once more widespread, however its past distribution is obscured by current land use practices.
Swampy Riparian Woodland was once widely scattered in the study area south of the Great Divide. This EVC occurred in broad drainage lines with slight gradients, on lower slopes near streams that were directly affected by riparian processes. Examples once occurred on the tributaries of the Yarra River between Healseville and Ringwood (for example Bushy and Olinda Creeks), and near Warragul on the lower reaches of the Bunyip River and Cannibal Creek. Soils are mostly of Quaternary age and are silt-rich river sands and gravels, although sites with heavier clay soils may also known.
As the name suggests, the overstorey of this vegetation type has a woodland structure which often forms mosaics with wetter tree-less areas dominated by sedges, rushes and many other plants associated with riparian environments. Swamp Gum Eucalyptus ovata andManna Gum Eucalyptus viminalis are the dominant overstorey species. A wide range of other eucalypts can be present, mainly as adventive species from the surrounding drier forests..
The understorey shrubs consist of Blackwood Acacia melanoxylon (as it rarely reaches tree-form in this community), Swamp Paperbark Melaleuca ericifolia, Prickly Current-bush Coprosma quadrifida, Hemp Bush Gynatrix pulchella, Tree Violet Hymenanthera dentata and Hop Goodenia Goodenia ovata, Black Wattle Acacia mearnsii and Snowy Daisy Bush Olearia lirata especially on levees. The ground stratum is the most characteristic feature of this EVC and is normally dense with graminoids including Leafy Flat-sedge Cyperus lucidus, Tall Sedge Carex appressa, Common Reed Phragmites australis and Common Tussock Grasss Poa labillardieri. These species compete for space with ferns.
This EVC occurs from the western slopes of the Paul Range through to Coldstream, south to the Pakenham area on pale soils. Grassy Forest occupies an ecological position between box-stringybark woodlands Valley Grassy Forest, Lowland Forest and Herb-rich Foothill Forest. It occurs on pale soils which have poor drainage during the wettest periods of the year. It is characterised by a dominance of Messmate and Eucalyptus obliqua and Narrow-leaved Peppermint Eucalyptus radiata with associated species including Candlebark Eucalyptus rubida, Eucalyptus goniocalyx, Red Stringybark Eucalyptus macrorhynca, Eucalyptus cephalocarpa and Yellow Box Eucalyptus melliodora and Swamp Gum Eucalyptus ovata and Manna Gum Eucalyptus viminalis around gullies or seepage areas. Whilst the overstorey composition resembles that for Herb-rich Foothill Forest, tree stature is often reduced and the understorey has greater affinities with drier vegetation types.
Understorey species include a diverse array of graminoids such as Red-anther Wallaby-grass Chionocloa pallida, Wallaby Grasses Danthonia spp., Spear Grasses Stipa spp., especially Veined Spear-grass Stipa rudis and Tussock Grasses Poa spp., with Weeping Grass Microlaena stipoides, Soft Tussock-grass Poa morrisii, Grey Tussock-grass Poa sieberiana, Velvet Tussock-grass Poa rodwayi, Variable Sword-sedge Lepidosperma laterale and Kangaroo Grass Themeda triandra usually at lower levels of abundance if present. Black Sheoke Allocasuarina littoralis, Black Wattle Acacia mearnsii and Blackwood Acacia melanoxylon can be conspicuous, and Thatch Saw-sedge Gahnia radula is typically prevalent. Forbs and perennial geophytes are also common and can include species such as Creeping Bossiaea Bossiaea prostrata, Pale Grass-lily Caesia spp., Golden Weather-glass Hypoxis spp., Early Nancy Wurmbea spp., Milkmaids Burchardia umbellata, Tall Bluebell Wahlenbergia stricta, Tufted Bluebell Wahlenbergia communis, Small Poranthera Poranthera microphylla, Stinking Pennywort Hydrocotyl laxiflora, Grass Trigger-plant Stylidium graminifolium, Blue Pin-cushionBrunonia australis, Vanilla Lilies Arthropodium spp., Shrubby Fireweed Senecio minimus, Annual Fireweed Senecio glomeratus, Cotton Fireweed Senecio quadridentatus, and Bent Goodenia Goodenia geniculata.
The Wetland Formation is rare in the study area and very few, small localised examples remain, largely due to the drainage of wetlands for agriculture. The formation described here, occurs in billabongs or other areas with standing water often in flood plains but may be more widespread. Nearly all of the environment where it could potentially occur has been dramatically altered and is invariably dominated by weed species. The species found in this vegetation include Common Reed Phragmites australis whichis often abundant and various sedge species including Tall Spike-sedge Eleocharis sphacelata withUpright Millfoil Myriophyllum crispatum usually conspicuous.
Riverine Escarpment Scrub*
This EVC occurs along rocky cliffs and slopes associated rivers and major creeks and may extend onto alluvial terraces in some situations. It occurs along the Yarra River in the Warrandyte-Yering area. It is characterised by a medium to tall shrub layer which often limits the regeneration of overstorey trees to the natural gaps in the canopy and results in a sparse overstorey. The ground layer is often open due to heavy shading and bryophytes may be a conspicuous feature.
The shrub layer is dominated by Burgan Kunzea ericoides. Other species generally include a suite of Pomaderris species with restricted a distribution restricted to this vegetation and a range of shrubs such as Snowy Daisy Bush Olearia lirata, Sweet Bursaria Bursaria spinosa, Correa glabra, Victorian Christmas Bush Prostanthera lasianthos, Prickly Currant Bush Coprosma quadrifida, Tree Violet Hymenanthera dentata, Hop Goodenia Goodenia ovata, Swamp Paperbark Melaleuca ericifolia and Wattles Acacia spp. The conspicuous forbs include the genera Pennyworts Hydrocotyl spp., Small Poranthera Poranthera microphylla, Wood Sorrels Oxalis spp., Geraniums Geranium spp., Galiums Galium spp., Raspworts Gonocarpus spp., Bluebells Wahlenbergia spp., and Groundsels Senecio spp. Ferns include the Maidenhair Fern Adiantum aethiopicum, Necklace Fern Aspleniumflabellifolium and the Rock Ferns Chelianthes spp. Graminoids are often conspicuous in this vegetation and include Lepidosperma laterale, Lomandra longifolia, and the genera Microlaena, Danthonia and Stipa. A range of riparian species will be present at localities nearer the river or creek.
Structurally this EVC was a tall forest dominated by River Red Gum Eucalyptus camaldulensis. The habitat is subject to annual flooding and takes upto three months to drain naturally. The exact composition of the vegetation is largely conjecture but it is considered likely that the structure of the understorey was primarily grassy and sedge-rich with many species shared with Plains Grassy Wetland. The most common species would have been Rush Sedge Carex tereticaulis, Brown-back Wallaby-grass Danthonia duttoniana, Swamp Wallaby-grasses Amphibromus spp., (Veined Swamp Wallaby-grass A. nervosa and River Swamp Wallaby-grass A. fluitans) Common Tussock Grass Poa labillardieri and Spike Rushes Eleocharis spp. There would also have been a large range of aquatic/wet site herbs also present.
EVCs of the Central Highlands and their map labels from the Biosis-Frood Pre-1750s mapping