Open Access

Robert Payne, Ross Wellington, Michael Somerville

• The vegetation and floristics of the coastal sandplains on the Umina-Woy Woy Peninsula on the northern foreshores of Broken Bay (lat 33° 30’ S, long 151° 15’ E), 40 km north of Sydney, are described from historical records, sampling of remnants and analysis of regional scale vegetation. Of the seven vegetation communities described, Umina Coastal Sandplain Woodland (UCSW) was originally the most extensive type of vegetation over the Umina-Woy Woy sandplain and on the seaward side of the Pearl Beach sandplain, and possibly on the sandplains at Patonga and Little Patonga. Characteristic tree species are Angophora floribunda and Eucalyptus botryoides; the latter appears to be more common at foreshore sites. Close to the sea and in swales at the base of hillslopes, littoral rainforest elements can be present. Patonga may have had significant inclusions of this vegetation. As a result of clearing for suburban development and its reduction to small remnants, UCSW and Freshwater Wetlands have been listed as an Endangered Ecological Communities under the NSW Threatened Species Conservation Act. A form of the closely-related Sydney Red Gum (SRG) complex occurs on a different SLU on the south-west side of Pearl Beach. A characteristic tree is Angophora costata. Site environmental differences between UCSW and the Sydney Red Gum Complex include their occurrence on iron podsols and humus podsols respectively. Regional vegetation classification and analysis shows that these vegetation units are distinctly different from each other. This is supported by historical evidence from surveyor notation on Crown Survey and land subdivision plans. Originally the Bangalay – Rough-barked Apple Woodland vegetation component of the Umina Woy Woy sandplain was defined by the NSW Scientific Committee for Umina Coastal Sandplain Woodland. Regional analysis now reveals the Red Gum-Red Bloodwood (RGBW) component now merges with this former community. The Pearl Beach vegetation remains separate. A re-definition of UCSW is now required. Management, particularly of UCSW, currently involves revegetation and regeneration works in the vicinity of existing reserves. However, because the depletion has been so extensive there is further opportunity to decrease the loss by utilising the wide riparian reserves and laneways where mature trees still exist. A major conservation concern is the modification and loss of the sandplain vegetation, particularly the wetlands. The historical Crown Survey plans highlight the extent of wetlands as an important ecological feature of the original sandplain landscape. The current study estimated that 83% of wetlands and 79% of riparian vegetation has been lost on the Umina-Woy Woy sandplain since European settlement.