From a knowledge of the current plants at Blackburn Lake Sanctuary and from similar areas in the Eastern suburbs as well as from pollen studies which look at plants which existed in earlier days, we have a good idea what plants would have been found at Blackburn before white settlement. The vegetation has been described and studied for many years by botanists. In general terms the most common large trees are eucalypts with wattles, grasses and some wild flowers. The plants are usually found in groups described as communities.
The original plants which can be found at Blackburn Lake Sanctuary, are known as indigenous plants. That is, they were found in this area before white settlement. Other plants, from other areas of Melbourne or the rest of Australia, are known as native plants.
More technically, in the broad vegetation description of Victoria, Blackburn Lake, along with most of the Melbourne region is described as Eastern Forest. The vegetation was open with dominant upper storey species being Eucalyptus viminalis, E. obliqua and E. ovata.
Around Blackburn Lake both Stringy bark and Yellow box open communities were found. The natural waterway of Gardiner's creek, prior to the creation of Blackburn Lake, also allowed for some riparian or water side vegetation which evolved in these poorly drained conditions.
The Stringybark community consisted of an upper storey of E. baxteri, (Brown Stringybark), E. obliqua, (Messmate), and E. cephalocarpa, (Silver leaf Stringybark). The Yellow Box community contained E. melliodora (Yellow Box) E. goniocalyx (Long leafed Box) and E. radiata (Common Peppermint) Both these communities would have been described as open Schlerophyll Forest.
The middle storey contains Acacia mearnsii, (Black Wattle), Exocarpos cupressiformis (Cherry Ballart) and Bursaria spinosa, (Sweet Bursaria). The understorey is grassy with Poa spp, Themeda triandra (Kangaroo grass), Danthonia spp (Wallaby grass) and Microlaena stipoides (Weeping grass)
Interspersed with the grasses are plants such as Arthrodopium strictum (Chocolate lily), Dianella longifolia (Pale or Smooth Flax lily) and Brunonia australis (Blue Pincushion). A variety of orchids would have also been found in the area.
In the areas where drainage would have been poor, Melaleuca ericafolia (Swamp Paperbark), Acacia verticillata (Prickly Moses) and Leptospermum spp (Tea tree) would have been dominant, along with riparian vegetation such as Carex appressa (Tall sedge) and Prunella vulgare (Self heal).
Clearing of vegetation has not only allowed for the invasion of exotic weeds, it has also meant that some ground flora may be more prevalent than in the days prior to European settlement. Examples include the dominance of Ghania radula (Thatch Saw-sedge) which prior to being burnt in January 1997 was growing extensively in the open conditions.
Some of the plants were used by the Aboriginal communities in the area as bush tucker and to provide fibre, medicines and other resources they needed.
As with most plant communities within Victoria, indigenous vegetation within Blackburn Lake Sanctuary has evolved with fire and, in the era prior to European settlement would have been able to regenerate following periodic bushfires. See the section on fires for further details.
Changes in the local environment modify, over time, the plants which can be found in the Sanctuary. The plants which are particularly vulnerable are the low ground cover plants. They are greatly affected by weed species coming in to take their place in the community. See the section on weeds for further details.
Fungi are also seen in the Sanctuary. There are approximately 50 different species of fungus. In Australia, fungi are very important for the growth and continued health of our trees and shrubs. Fungi live in a symbiotic relationship with trees, they provide nutrients such as nitrogen which are needed by the trees and in return the trees provide nutrients for the fungi. A major role for fungi in the ecosystem is to decompose wood and leaves which have fallen to the ground. Some of them are posionous and cannot be eaten.
Foreman, D.B., and Walsh, N.G. Flora of Victoria Vol.1 Introduction Inkata Press 1993, p 97.
Ibid p 81
Calder, W, Pike, J. Blackburn Lake Sanctuary an environmental assessment and master plan, University of Melbourne 1976. Ibid p 20
Groves, R.H., Australian Vegetation, 2nd Edition, Cambridge Press1994, p 198.
Society for Growing Australian Plants, Flora of Melbourne, Hyland House Publishing Pty. Ltd. 1993
Ibid Calder and Pike p 23