When planning to revegetate an area, it is worth visiting patches of remnant bush, to get an idea how the trees, shrubs and ground plants have changed on your land over the past 200 years. In the mountain and foothills in the east of the guide area, one can easily find patches of bush which contain lots of native plants, and without too much trouble, we can develop a mental picture of what reasonably 'natural' bush looks like. On the plains, however, it can be hard to find a natural looking remnant, and it can sometimes be almost impossible to determine how much the land has changed over the past 200 years, as very little is left to indicate changes in the past.
Woodland remnants on public and private land serve many important functions, including soil and water conservation, habitat for plants and animals, sources of native seeds for future revegetation, and to provide a model to guide revegetation efforts. These remnants are also important for our local history and heritage, as they are the only places where our children can see what the region looked like when the first white explorers and settlers entered, and how we have altered the landscape since then.
So where can such sites be found on the plains? Most of the best woodland remnants are small, hidden between the extensive crops and grazed paddocks. Not surprisingly, most native plants tend to survive in places which have escaped past development, and which have not been ploughed, fertilised or continuously grazed. Typical sites include small cemeteries, along railway lines and little-used travelling stock reserves, and on some stream frontages. Often the grassy areas within country airports and race tracks contain many plants which have vanished from the surrounding region.
A number of botanists have studied the plains and have described general changes in the landscape. They have found that the most important activities which have caused losses of native plants are continual grazing or grazing at high stocking rates, soil disturbance, fertilisation and water run-on, all of which deplete native species and promote exotics, including many weeds.
When an area which has rarely been grazed by stock gets grazed more intensively, the first species to disappear are those which the stock prefer to eat (the palatable species), and which cannot survive being continuous grazed down. Gradually, other species decline and disappear, and at the same time many introduced species become more abundant. As most native woodland plants are perennials and many exotics are annual, the overall effect of increasing grazing is to change a woodland remnant dominated by perennial species to a degraded site dominated by introduced annuals. Many palatable native shrubs also disappear, removing habitat for nesting birds. Most people are so used to seeing roadsides and neglected paddocks dominated by tall weeds, that it is a surprise to discover that many small, undisturbed patches of bush actually are very good at resisting weed invasion, until the remnants get disturbed, after which the weeds then move in.
Because of the magnitude of the landscape changes over the past 200 years, it is often difficult to be confident about which native species originally grew in a particular place 200 years ago. Over most of the White Box woodlands, the landscape appears to have been relatively open originally, with scattered shrubs and a grassy understorey. The original grasses were not the Oats and Phalaris which now dominate most roadsides in the region, but the native Kangaroo Grass and Tussock-grass. Kangaroo Grass is rapidly eaten out under moderate stocking levels, and has disappeared from all but small areas. Many of the native grasses which are most often observed nowadays, such as Red-grass and Purple Wire-grass, probably became more common as Kangaroo Grass and Tussock grass were eliminated.
To many people, the simplest way to identify a high quality woodland remnant is the wealth of native wildflowers which, in a good season, can cover the ground in a carpet of colour. It is a pity such species have disappeared from our roadsides as they would make a colourful display, far more preferable to the bands of Paterson???s Curse and Capeweed. In spring, many small cemeteries are bejewelled with the yellow Everlastings and Scaly Buttons, erect spikes of Creamy Candles, Purple Donkey-orchids, nodding yellow Yam-daisies, and sprays of Native Bluebells. Not surprisingly, many gardeners and local councils are using many of these plants in colourful garden beds.
The south-west slopes region does not contain a large number of species which are nationally rare or threatened. Instead, the extensive foothill and plains land systems contained many widespread species which also occurred in many other regions. Nowadays, it is important not to focus too much on Nationally rare or threatened species, simply because (by definition) these plants occur in very few places and are absent from many otherwise important remnants. In most places, a more important focus is the large group of species which tenuously survive in many cemeteries, railway easements, stock routes and the odd, lightly grazed paddock, because these species represent the core natural heritage of the woodlands of the south-west slopes region. Regrettably, many of these species are still slowly declining throughout the region (an in many other regions as well), as many small remnants are unwittingly degraded or destroyed.
By appreciating and protecting the small remnants which survive in the region, we can save our own local history and natural heritage, plus the seed supplies and natures models for future revegetation efforts. Fortunately, most remnants can be protected very simply, by ensuring that the soil is not disturbed or dug, that fertiliser and water run-on are excluded, and that grazing levels are not increased. No doubt, future revegetators will doubly respect our efforts to conserve these natural seed sources now.
Creamy Candles - Stackhousia monogyna
Common Everlasting - Chrysocephalum apiculatum
Kangaroo Grass - Themeda triandra
Native Bluebells - Wahlenbergia species
Purple Donkey-orchid - Diuris dendrobioides
Purple Wire-grass - Aristida ramosa
Red-grass - Bothriochloa macra
Scaly Buttons - Leptorhynchos squamatus
Tussock-grass - Poa sieberiana
WhiteBox - Eucalyptus albens
Yam-daisy - Microseris scapigera