It is an area of high biodiversity, existing on poor sandstone soils, with regular wildfires, and moderate rainfall.

[1][2][3][4] The Ridgetop Woodland is a low eucalypt forest having a diverse sclerophyll shrub layer, mallees and open groundcover of sedges that sit on the Triassic Hawkesbury sandstone plateaux, which encircle the Sydney Basin.

[6] It incorporates Coastal Sandstone Ridgetop Woodland, which is found up to 600m above sea level in areas receiving an average annual rainfall ranging from 850 to 1650 mm.

[5] The area is dominated by Corymbia eximia and Eucalyptus sieberi, which shape a sporadic overstorey enclosed with large shrubs such as Banksia serrata, Leptospermum trinervium and Hakea dactyloides.

Smaller shrubs including Leucopogon setiger and Dillwynia floribunda are salient towards the edge of the rock shelf.