Open Access

Judy Lambert, Geoff Lambert, Belinda Pellow

• Eastern Suburbs Banksia Scrub (ESBS) is a listed Endangered Ecological Community that becomes senescent and loses species diversity in its plant cover in the long-term absence of fire. However, the reintroduction of fire into remnant vegetation within urban areas presents management challenges and selective thinning is sometimes presented as an alternative management option. This project sought to evaluate fire and selective thinning of dominant species as tools for reinvigorating senescent ESBS. Two peri-urban ESBS sites at North Head, Sydney, New South Wales, scheduled for hazard reduction burns to protect assets, were surveyed for their floristic attributes. Surveys were carried out in 7 x 7 metre quadrats, one third of which were fenced after fire to assess predation by herbivores. Similar quadrats were established on adjoining unburnt sites from which dominant species were removed through selective thinning. Twelve months after treatment (and to a lesser extent at 6 months) burned ESBS displayed greater vigour and diversity than did thinned sites. Burned ESBS had more native plants, greater plant cover, more native species, greater species diversity and fewer weeds than did thinned ESBS. Burned and thinned ESBS sites had significantly low overlap in native species mix. Areas that had been fenced after fire had “superior” attributes to those that had not been fenced. There was nearly complete overlap of species between fenced and unfenced ESBS subjected to fire. The results suggest that fire can be used advantageously to rejuvenate this type of heath and that this method produces superior results to thinning, but with a different species mix. These advantages accrue with time. The results of either method would be greatly inferior were attempts not made to control predation by exotic herbivores such as rabbits.