Characteristics of Threatened Communities

Semi-arid Herbaceous Pine Woodland Community

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Semi-arid Herbaceous Pine Woodland Community

The Semi-arid Herbaceous Pine Woodland Community is a woodland or open woodland mainly dominated by slender cypress-pines, and with few or no shrubs. The dominant tree is Slender Cypress-pine (Callitris gracilis), with occasional Buloke (Allocasuarina luehmannii) towards the margins. Shrubs are uncommon but typically include Small Cooba (Acacia ligulata). At Hattah-Kulkyne and elsewhere in the far north of the State, Narrow-leaf Hopbush (Dodonaea viscosa subsp. angustissima) has become abundant in many current and former stands.

The ground layer of this community type is overwhelmingly herbaceous; typical herbs are Poached-eggs Daisy (Polycalymma = Polycalymma stuartii), Mediterranean Turnip (Brassica tournefortii), Tangled Burr-Daisy (Calotis erinacea), Cushion Knawel (Scleranthus minusculus), Australian Stonecrop (Crassula sieberiana), Velvet Tobacco (Nicotiana velutina), Flannel Cudweed (Actinobole uliginosum), Sand Catchfly (Silene apetala = S. apetala var. apetala) and Mediterranean Catchfly (Silene nocturna).

This community was once widespread on relatively dry, deeper sandy soils of the Mallee, especially on the crests of dunes, lunettes and sand-ridges, though many of these sites have since been cleared for farming. It is also present on public land in parts of the Big Desert and Sunset Country. The community appears to be sensitive both to fire and browsing by rabbits.

Semi-arid Herbaceous Pine-Buloke Woodland Community

The Semi-arid Herbaceous Pine-Buloke Woodland Community is a woodland or open woodland typically dominated by both slender cypress-pine and buloke trees, without a shrub layer and with a largely herbaceous ground layer. It occurs where the soil surface is sandy but finer-grained from a few centimetres depth downwards.

The dominant trees are Slender Cypress-pine (Callitris gracilis) usually in association with Buloke (Allocasuarina luehmannii). The ground layer consists largely of herbs such as Australian Stonecrop (Crassula sieberiana), Dense Crassula (Crassula colorata), Hard-headed Daisy (Brachyscome lineariloba), Small Purslane (Calandrinia eremaea) and Austral Carrot (Daucus glochidiatus), with the introduced grasses False Hair-grass (Pentameris = Pentaschistis airoides) and Arabian Grass (Schismus barbatus). Where this community occurs close to dunes or ridges, there is often a Semi-arid Herbaceous Pine Woodland Community on higher ground on the deeper, drier sand of the crests.

Before the accretion of loose surface sand that followed European settlement, occupied sites were subject to occasional waterlogging. This community type is mostly restricted to infrequently-burnt public land in the north-west of the state, especially in the Murray-Sunset, Hattah-Kulkyne and Wyperfeld National Parks, but also occurs on some other sites licensed for grazing.

Semi-arid Northwest Plains Buloke Grassy Woodland Community

The Semi-arid Northwest Plains Buloke Grassy Woodland Community is open woodland in which Buloke (Allocasuarina luehmannii) is the dominant tree, sometimes in association with Black Box (Eucalyptus largiflorens) and/or Yellow Gum (E. leucoxylon).

A shrub layer is present, with Gold-dust Wattle (Acacia acinacea) as the dominant shrub, usually accompanied by smaller sub-shrubs such as Variable Sida (Sida corrugata), Frosted Goosefoot (Chenopodium desertorum = C. desertorum subsp. desertorum), Nodding Saltbush (Einadia nutans = E. nutans subsp. nutans), Fuzzy New Holland Daisy (Vittadinia cuneata = V. cuneata var. cuneata) and Woolly New Holland Daisy (Vittadinia gracilis). The ground layer consists of grasses such as Bristly Wallaby-grass (Danthonia setacea = Rytidosperma setaceum), Feather Spear-grass (Austrostipa elegantissima), and Crested Spear-grass (Austrostipa blackii) accompanied by such species as Scented Mat-rush (Lomandra effusa), Grassland Wood-sorrel (Oxalis perennans) and Hare’s-foot Clover (Trifolium arvense = T. arvense var. arvense).

This community type was once widespread across the plains of north-western Victoria and the Wimmera, on sites where soils are relatively fertile and subject to seasonal water-logging and little fire. Most of the sites on which it occurred were settled early and are now private land mainly cleared for farming.

Semi-arid Shrubby Pine-Buloke Woodland Community

The Semi-arid Shrubby Pine-Buloke Woodland is an open woodland or woodland community with a mix of slender cypress-pine and buloke and a characteristic shrub component. The community is dominated by Slender Cypress-pine (Callitris gracilis) and variable numbers of Buloke (Allocasuarina luehmannii) trees.

The shrub layer consists of often-widespread species such as Ruby Saltbush (Enchylaena tomentosa = E. tomentosa var. tomentosa), Slender or Narrow-leaf Hop-bush (Dodonaea viscosa subsp. angustissima), Weeping Pittosporum (Pittosporum angustifolium), Hedge Saltbush (Rhagodia spinescens), Pimelea Daisy-bush (Olearia pimeleoides), Cattlebush (Alectryon oleifolius subsp. canescens) and Horned Bassia (Sclerolaena diacantha). The ground layer is dominated by herbaceous annuals such as Small Purslane (Calandrinia eremaea), Mediterranean Turnip (Brassica tournefortii), Austral Carrot (Daucus glochidiatus), Little Medic (Medicago minima), Hairy Burr-daisy (Calotis hispidula), Hard-headed Daisy (Brachyscome lineariloba) and Flannel Cudweed (Actinobole uliginosum). Longer-lived hebs are represented by Dissected New Holland Daisy (Vittadinia dissecta = V. dissecta var. dissecta), and Nodding Saltbush (Einadia nutans = E. nutans subsp. nutans). Although grass species are not diagnostic of this community, Feather Spear-grass (Austrostipa elegantissima) is often present.

Semi-arid Shrubby Pine-Buloke Woodland is typically found on flat or slightly undulating land with sandy loam soils over finer-grained substrates, where the soil is occasionally waterlogged. It is found mainly in the near north-west of the State, typically on sites that have been free of fire for many decades. Nearly all the sites are on public land.

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