REHABILITATION OF RIVERBANK AND BEAUTIFICATION OF WINDMILL WALK
Gilgandra Shire Council recently constructed a new carpark behind Miller Street, the main street of Gilgandra, on the Castlereagh River. Included in the works was a specific caravan parking site, and an extension to the existing walking/cycling track known as Windmill Walk. In order to successfully complete this project, Gilgandra Shire Council needed to implement weed control measures, as well as stabilise the riverbank at this site. It was considered appropriate to extend these works to control weeds across a larger area of the river, and to improve the natural environment through revegetation works with native plant species in order to increase both the habitat and amenity values of the area.
The riverbank area benefits from a canopy of mature River Redgums (Eucalyptus camaldulensis), however, the understory was dominated by invasive weeds such as creeping mallow, capeweed, dandelion, nettles, clover and kikuyu. Additionally, some woody weeds were present at the site including peppercorn and cedar trees. It was considered that an integrated weed management approach was the most appropriate action to ensure the long-term control of weeds. The woody weeds were removed by cutting them down and removing the bulk of the tree. The stump and root system were left in situ in order to minimise any impacts on riverbank stability. All native trees and plants have been retained.
The integrated weed control being conducted at the site incorporates a series of measures to ensure long-term success. The methods being used include slashing to initially reduce the density of weeds, whipper snipping to prevent seed development and dispersal, as well as steam application and blowtorch to directly kill weeds. Additionally, where appropriate, hand weeding was undertaken to manually remove weeds from the site. Gilgandra Shire Council elected not to use any herbicide as part of this project due to the proximity to the river.
To further ensure the success of this integrated weed control approach, the site was mulched to suppress any weed germination from the remaining seed bank, and then revegetated with native species including Hardenbergia violacea which will directly outcompete weeds that may germinate.
Over 2,500 native plants will be established at the site with many of these being Hardenbergia violacea. This plant in particular has been selected due to its hardiness, attractive flowers and ability to spread across the ground allowing it to outcompete weed species. Ongoing maintenance at the site will include watering to ensure the successful establishment of the plants, additional mulching and targeted weed control as necessary.
This project has been developed to restore native vegetation back to the riverbanks at this site which is anticipated to attract a range of native bird species and pollinators. The project is proudly supported by the Environment & Waterways Alliance to the value of $20,000.