Conservation in Action: Vaucluse House bush care
Today was our third session in the past few months and you can already see a big improvement in the visual appearance and presentation of the boundary. Over time, as we open up the lower canopy and expose more of the sandstone ledges and cliff faces, the bushland will return to the more ‘Sublime’ visual appearance and composition it had in colonial times. Right now, it features a textbook selection of herbaceous and woody weeds widely found in Sydney bushland, including some surprise interlopers from other parts of Australia, but over the next 12 months I hope we will wrestle it back under control.
Old photographs show the backdrop to Vaucluse House as a much drier and exposed site covered with a type of low open woodland vegetation, once widespread on the sandstone ridges around the southern shores of Sydney Harbour, but now only surviving in small pockets. The best remaining example in good condition is nearby at Nielsen Park. The exposed sandstone outcrops and cliffs supported mainly Swamp Mahogany (Eucalyptus robusta), Forest Red Gum (Eucalyptus tereticornis), and Coastal Honeysuckle (Banksia integrifolia), with smaller understorey trees like Cheese Tree (Glochidion fernandii), False Rosewood (Synoum glandulosum) and Water Gum (Tristanopsis laurina). Sandstone loving shrubs such as Weeping Sally (Acacia floribunda) and Spider Grevillea (Grevillea sericea) would grow in bright light on the woodland verges and openings. Along the boggy verges of the creek channel would have been sedges and ferns, but the Rough Tree Fern (Cyathea cooperi) now present in large numbers is an introduced pest species.
Where there are high soil nutrient loads and water some native species become dominant and eventually block the growth of other desirable native species, so a challenge is how to control these ‘seral interlopers’ – such as Sweet Pittosporum (Pittosporum undulatum), Native Quince (Alectryon tomentosus), and Golden Wreath Wattle (Acacia saligna).
Unfortunately this little strip of bushland will never be ecologically viable on its own without continuous management to limit the growth of invasive species and encourage the regeneration of the locally endemic ones.