Commonwealth of Australia

Inclusion of ecological communities in the list of threatened ecological communities under section 181 of the Environment Protection and Biodiversity Conservation Act 1999

I, PETER ROBERT GARRETT, Minister for the Environment, Heritage and the Arts, pursuant to section 184(1)(a) of the Environment Protection and Biodiversity Conservation Act 1999, hereby amend the list referred to in section 181 of that Act by:

including in the list in the critically endangered category

Grassy Eucalypt Woodland of the Victorian Volcanic Plain

as described in the Schedule to this instrument.

Dated this….....Eighteenth...............day of…................June...............2009.

Peter Robert Garrett

Minister for the Environment, Heritage and the Arts

SCHEDULE

Grassy Eucalypt Woodland of the Victorian Volcanic Plain

The Grassy Eucalypt Woodland of the Victorian Volcanic Plain is an ecological community that is endemic to Victoria, with occurrences between Melbourne and the Hamilton district. Its bioregional distribution is limited to the Victorian Volcanic Plain bioregion

The ecological community typically occurs on flat to gently undulating plains and associated stony knolls, generally at elevations up to 500 metres above sea level. The soils of the plain are heavy grey to red cracking clays, with black cracking clays common in the low-lying areas and tend to be fertile but poorly draining.

The Grassy Eucalypt Woodland of the Victorian Volcanic Plain is a type of open eucalypt woodland with a predominantly grassy understorey.

The tree canopy is typically dominated by Eucalyptus camaldulensis (River Red Gum). River Red Gum may be locally replaced by Eucalyptus ovata (Swamp Gum) or E. viminalis (Manna Gum) at sites that receive higher rainfall, or by Eucalyptus microcarpa (Grey Box) or E. melliodora (Yellow Box) at sites that receive lower rainfall. Other tree species that may be present in the canopy layer include Acacia implexa (Lightwood), Acacia mearnsii (Black Wattle), Acacia melanoxylon (Blackwood), Allocasuarina verticillata  (Drooping Sheoak) and Banksia marginata (Silver Banksia). Hybrids of the eucalypt species may also be present in the tree canopy.

A mid layer may be present and typically comprises various species of Acacia though other shrub genera may be present depending on the characteristics of the site, e.g. rainfall, stony knolls. The crown cover of shrubs underneath the tree canopy is typically less than 30%, not including regenerating native canopy trees.

The crown cover of native trees and shrubs that are 5 metres or more in height, and occupy the canopy and mid layers, generally lies between 5 and 30%. Exceptions are:

• a lower limit of 0% applies for the derived grassland state of the ecological community; and
• an upper limit of 70% applies if regenerating trees less than 5 metres tall are included.

The ground layer is the dominant layer of the understorey and is dominated by native grasses and/or other herbs. Low or prostrate shrubs also may be present. Native grasses that commonly occur in the ground layer include: Austrodanthonia species (Wallaby Grasses), Austrostipa species (Spear Grasses), Microlaena stipoides (Weeping Grass), Poa species (Tussock Grasses) and/or Themeda triandra (Kangaroo Grass). The ground layer typically contains at least some native species from the following genera: Acaena, Arthropodium, Calocephalus, Chrysocephalum, Dianella, Dichondra, Geranium, Leptorhynchos or Solenogyne.

The key diagnostic attributes of the Grassy Eucalypt Woodland of the Victorian Volcanic Plain ecological community are as follows.

• The tree canopy is typically dominated by Eucalyptus camaldulensis (River Red Gum) but may be dominated by other species in response to variations in rainfall and/or localised landscape features. At sites that receive higher rainfall, Eucalyptus ovata (Swamp Gum) or E. viminalis (Manna Gum) may replace River Red Gum as the dominant species in the canopy layer. At sites that receive lower rainfall, Eucalyptus microcarpa (Grey Box) or E. melliodora (Yellow Box) may replace River Red Gum as the dominant species in the canopy layer.
• The understorey is dominated by a native ground layer with these features:
  • one or more of the following native grass genera typically dominates the perennial ground layer: Themeda, Austrodanthonia, Austrostipa, Poa and/or Microlaena; and
  • one or more of the following native herb genera are typically present: Acaena, Arthropodium, Calocephalus, Chrysocephalum, Dianella, Dichondra, Geranium, Leptorhynchos or Solenogyne.
• Its distribution is limited to the Victorian Volcanic Plain IBRA Bioregion.
• Its occurrences are limited to Quaternary basalt soils on low elevation plains and stony rises on the basalt flows.

The ecological community exhibits a degree of  variation in its appearance and composition across its range due to differences in rainfall, landscape features, seasonality and management history across its range. In addition to its typical open woodland expression, the Grassy Eucalypt Woodland of the Victorian Volcanic Plain ecological community also includes:

• localised low stony or rocky rises that lie within, or adjacent to, a patch of eucalypt woodland. The canopy of River Red Gum on these stony rises may be replaced by a shrubland of Acacia species, Melicytus dentatus (Tree Violet) and/or Bursaria spinosa (Sweet Bursaria), or  a low woodland of Allocasuarina verticillata (Drooping Sheoak).
• sites where dense, regenerating tree saplings may temporarily increase the tree crown cover up to 70%.
• derived native grasslands where the native tree and shrub layers have been removed such that their crown cover is 0-5%, but a predominantly native ground layer remains. There should be clear evidence that the site formerly contained the Grassy Eucalypt Woodland of the Victorian Volcanic Plain ecological community.