From lawn to living lab
A site trialling various methods of ecosystem restoration is now well into its re-imagined life as a bushland recovery zone.
Covering around 800 square metres, the site is surrounded by remnant bushland on three sides and contains a stand of mature trees. The area is easily accessible on foot from alongside the campus lake.
The project commenced in Spring 2010. It was predicted that if the area’s regular mowing regime was phased out and replaced by assisted regeneration work to control weeds, native ground and shrub species would begin to re-colonise from the natural seed bank.
Impeded drainage caused by surrounding land uses had created an excessively soggy environment through parts of the proposed restoration zone. The solution was to fashion an intermittent water course, involving an excavated trench backfilled with a ‘sock’ of gravel wrapped with geo-fabric, and minor modification of topography to direct runoff through the site and out to the Mars Creek lake.
A Restoration Mosaic Established
Additional to suppressing the former lawn grasses and weeds, other methods include:
- Spreading harvested Kangaroo grass thatch during winter to expand the coverage of native seed of this key colonising species
- Transplanting native Bracken Fern clusters, to rapidly establish new habitat for invertebrates
- Translocations of leaf litter from nearby forest patches to support additional germination and replenish the soil microbial diversity
- Limited native planting around disturbed soil areas to fringe the intermittent water course
- A test plot created for the use of direct seeding with native Sydney region grasses, to provide rapid re-establishment of a native ground layer.
From this array of different interventions, colonisation was able to occur from both the edges and middle of the site, with all ‘fronts’ eventually converging in a mosaic pattern.
Diversity now reigns across the entire former lawn area, with at least twenty five different species comprising the native understory. Species re-established include Blady Grass (Imperata cylindrica), Kangaroo Grass (Themeda australis) Flax Lilly (Dianella caerulea) Tufted Hedgehog Grass (Echinopogon caespitosus), Basket Grass (Oplismenus aemulus), Sydney Golden Wattle (Acacia longifolia), and Native Rice Flower (Ozothamnus dismifolium). Fallen logs amid the colonising vegetation add to the site’s habitat diversity.
Full list of native plants currently found on site.
Community Assistance and Recognition
Many people have assisted in the restoration work. Visiting school groups were involved in planting the watercourse edges. A team of over thirty from Macquarie’s Human Resources department dedicated a day of their community volunteering leave to come and remove weeds from the site.
The project received an Innovation Award for ‘Best Bushcare Site’ at City of Ryde’s Spring Garden Competition.