Greening corridors, New South Wales
Vegetation is a vital component of the transport corridors of New South Wales. Just some of its many benefits include: adding character and interest to roads and streets; screening traffic and improving views; providing habitat; providing shade; minimising erosion on road verges, cuttings and embankments; and absorbing carbon dioxide.
Road transport projects can include significant areas of native tree and shrub planting and grasslands. Each year hundreds of thousands of trees are planted or sown into road verges. These trees, shrubs and grasses generally originate from native seed collected in NSW, which ensures the trees have the best chance of survival, use least water and fit in well with the forests and ecosystems of this part of Australia.
Landscape architects and ecologists work together to prepare vegetation plans, designed in harmony with the broader landscape character. These drawings are then costed and the plants sourced from local nurseries. The vegetation can be established using seed that is sown directly into roadsides, or using plants grown from seed in nurseries and then transplanted into verges and medians.
On large projects tens of thousands of trees can be planted, which mature to become great woodlands corridors. Examples include the Pacific Highway, or avenues of honour such as on Remembrance Driveway (Hume Highway) between Sydney and Canberra. In towns and cities, shrubs and trees are used to create a seasonally attractive and environmentally beneficial public domain.
Although roadside vegetation matures and improves with age, it needs maintenance to help it establish, keep it from damaging roads and bridges and keep it from encroaching safe sight lines and clear zones. Weeding, watering and thinning needs to be carried out regularly.
In time this dedication to the landscape will improve our towns, cities and regional areas. In terms of the whole NSW state road system, it is estimated that the total landscape area is approximately 170,000 hectares. This is a significant estate and roughly equivalent to 16 million tonnes of carbon offset.