WESTWARD BOUND
- with the Royal Geographical Society of Queensland -
Helen Chapman

I thought you might be interested in a few highlights of the above trip. It took us through Bourke, then following the Darling River through Tilpa and the Paroo River Overflow to White Cliffs, and thence to three national parks - Mootwingee north of Broken Hill, south to Kinchega among the Menindee Lakes, and Mungo. David (Chapman) had the job of Resource Person, interpreting the landscape through a geographers eye, and mine was to name the plants.

In contrast to this time last year, when the country was bare of vegetation, this year it was ablaze with colour after good rains all winter, especially in September. The country was a picture - carpets of flowers, mostly yellow and white Asteraceae amongst the many shades of green - from the silver leaves of the mulgas to the shiny-leafed Dodonaeas with fruits in hues of yellow-green to bright red - and all against the background of the red sand. The Leopardwood trees (Flindersia maculosa) with their beautiful bark, sometimes standing alone and often in clumps, were in full flower. Great stuff!!

Mootwingee National Park is in a rocky red sandstone range showing massive beds of conglomerate. It you dont want to climb for a view, the walks between the cliffs along the white sandy creek beds lined with River Red Gums are great. There is heaps of other vegetation as well, with a swim in the waterholes. Theres lots of evidence of aboriginal occupation of the area, many cave paintings and rock art. Some areas are closed to the public. A tour with interpretation by aboriginal guides brought the meaning of the art work alive.

The main trees on the sandstone hills are the mulga (Acacia aneura) and the white cypress (Callitris glaucophylla). On the flats there were many flowers, including a carpet of bright yellow dwarf cup flowers (Chrysocoryne pusillus) and several Ptilotus species in colours of green, pink and white.

At Kinchega National Park we had intended camping on the banks of the Darling, but the threat of a storm sent us scurrying off the black clay of the alluvial river flats to the safety of the well-grassed caravan park at Copi Hollow. The rain held off until the following evening, so we were able to explore the lake system that is fed by the meandering Darling River.

The dominant trees along the river were the Black Box (Eucalyptus largiflorens), Coolibah (Eucalyptus microtheca) and River Red Gum (E. camaldulensis), with colourful Darling Pea (Swainsona greyana) growing between. On the western side of the lake could be seen areas of vineyards, one of many horticultural pursuits here in an area that is relatively free from many of the pests of other areas - all irrigated by the Menindee Lakes system.

We investigated Maidens Pub at Menindee, visited by Burke and Wills in 1860 - an outback pub typical of that vintage, built around a verandah courtyard filled with plants and shade, and imagined how popular it would be on a hot summer day.

But it was Mungo National Park that we were keen to see. Mungo is only one of a chain of old freshwater lakes that formed the Willandra Lakes system that dried up about 15,000 years ago as the worlds climate changed at the end of the last Ice Age. From a vantage point near the camp, you look across the dry bed of the lake to a bank of white dunes, the crescent-shaped lunettes, so called the Walls of China.

The lake bed is now covered with vegetation, mostly bladder saltbush. Try to imagine the scene when it was filled with water and teeming with fish, and the life of the aborigines who lived around it. As the lake dried the clay of the bed was riven by the prevailing winds to form the lunettes. These were eventually stabilised by vegetation and it was only the erosion of the dunes by sheep and rabbits that exposed the evidence of aboriginal occupancy. Several skeletons have been examined and then re-buried to prevent deterioration. Mungo Man 3 has been dated to 42,000 years before present.

Until a few years ago, the lunettes were advancing eastward at the rate of a metre per year, but this has been reduced to between 1cm and 5cm per year by plantings. The parks found that introduced plants like Horehound, Wild Tobacco and Yellow-top Daisy were the best original colonisers to hold the sand. Then native plants would move in.

Native Weeping Pittosporum (Pittosporum phylliraeoides) seemed to be the main shrub on the residuals. These are pillars left standing amongst the eroded clay and still held by native vegetation. Estimates are that in 150-200 years the lunettes will be completely revegetated, but that also means an end to further archaeological finds. The guide here was excellent. Walking alone, you would miss the aboriginal archaeological sites and his interpretation of them added much to your understanding.

At Mungo we camped under beautiful huge spreading Wilga trees that were in flower. The other main trees in the area were the Callitris, Belah (Casuarina cristata) and Rosewood (Alectryon oleifolius).

We passed through seemingly endless plains dotted with saltbush, mainly Black Bluebush, then through mallee country with its mosaic of movement and colour.

The plant that intrigued me most of all on the trip was one called Wires-and-Wool. Its proper name is Angianthus burkittii (Asteraceae). It is as prostrate as a plant can be, ie. dead flat, with wiry reddish stems and very small narrow leaves. At the ends of these long stems are dense white woolly flowerheads that are closely pressed to the ground. It really does look like wires and wool.

I thought the coach had run over it, flattening it, but no, that is the way it grows. It only appears after rain, usually on bare soil, like the side of a road, and it is usually unnoticed until it takes on its characteristic appearance. And I didnt even get a photo!