Southern Highlands Shale Woodlands Conservation Project

Southern Highlands Shale Woodlands at Oxley Hill Reserve Bowral

Southern Highlands Shale Woodland (SHSW) is a threatened ecological community (TEC). It is characterised by an assemblage of plants that are primarily found on clay soils derived from Wianamatta Shale, with some communities existing on a Shale-Basalt mix or intergrade.

An ecological community is a group of trees, shrubs and ground cover plants that occur together in a particular area. An endangered ecological community is facing a high risk of extinction in the immediate future.

Due to clearing, it mostly occurs in scattered patches of less than 5 hectares in area, with approximately less than 5-10% of the original extent now remaining.

SHSW is variable in structure and composition with three forms, known as:

  1. typical,
  2. tall/wet, and
  3. short/dry.

Common species found in SHSW include;

  • Tree layer: Narrow-leafed peppermint (Eucalyptus radiata), white stringybark (Eucalyptus globoidea) and mountain grey gum (Eucalyptus cypellocarpa)
  • Shrub layer: Black wattle (Acacia mearnsii), blackwood (Acacia melanoxylon), hop goodenia (Goodenia ovata) and yellow tea-tree (Leptospermum polygalifolium)
  • Ground layer: Kangaroo grass (Themeda australis), Austrostipa rudis and Weeping grass (Microlaena stipoides) 

Intact patches of SHSW are important for a variety of native animals, including threatened species such as;

  • Giant burrowing frog
  • Southern myotis
  • Koala
  • Powerful owl
Conserving Southern Highlands Shale Woodlands

Southern Highlands Shale Woodlands are a defining part of the Wingecarribee Shire’s natural identity. Found nowhere else, this ecological community occurs mainly on clay soils and provides vital habitat for iconic species such as the koala, powerful owl, and glossy black cockatoo.

Sadly, Southern Highlands Shale Woodlands is threatened and at risk of extinction. With most remnants located on private land, active conservation is essential to protect, restore, and enhance this endangered ecological community—ensuring it survives for future generations.

Status

Listed as threatened under the NSW Biodiversity Act 2016 and the Commonwealth Government’s Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act). Note: there is a slight difference in its name between the State and Federal Listing.

  • NSW: Endangered Ecological Community - Southern Highlands Shale Woodlands in the Sydney Basin Bioregion.
  • Commonwealth: Critically Endangered Ecological Community - Southern Highlands Shale Forest and Woodlands in the Sydney Basin Bioregion.  
Where is it found?

Southern Highlands Shale Woodlands (SHSW) is mainly found in the Wingecarribee Shire Local Government Area (LGA) but may occur elsewhere in the Sydney Basin Bioregion.

Within the Wingecarribee Shire it can be found in rainfall areas that range from 1400mm in the east to 900mm in the west. The amount of rainfall can impact the form of SHSW found in an area:

  • Typical form is found in areas with moderate rainfall.
  • Tall/wet form is found in areas with higher rainfall and soil moisture, and often in more sheltered areas.
  • Short/dry form is found in areas with lower rainfall, that can be more exposed to weather conditions. 
What are the main threats?

Over 90% of the historic extent of Southern Highlands Shale Woodlands (SHSW) has been lost through clearing. The remaining patches of SHSW are still threatened by:

  • Clearing of vegetation, including under scrubbing and fragmentation through thinning intact patches.
  • Inappropriate harvesting of firewood.
  • Inappropriate fire regimes.
  • Grazing and trampling of vegetation by domestic stock and by feral herbivores (e.g. deer).
  • Weed invasion.
Conservation efforts

To reduce the risk of extinction of Southern Highlands Shale Woodlands (SHSW), the following recovery actions are required:

  • Avoid further clearance and fragmentation of intact patches of SHSW.
  • Protect patches through restricting stock grazing and managing invasive weeds and vertebrate pests (e.g. rabbits and deer).
  • Retain, restore and expand current patches through revegetation efforts and allowing natural regeneration to occur.
  • Increase community awareness about SHSW, its importance and ways that the community can get involved to protect the ecological community.

Wingecarribee Shire Council has received funding via the NSW Government to undertake conservation efforts to protect and enhance patches of Southern Highlands Shale Woodlands. Council will be delivering engagement opportunities for the community to learn more about this threatened ecological communities, including planting days.

Wingecarribee dieback study

Generally, dieback in trees has been attributed primarily to extreme climate events over the last approximate seven years. Causes such as extreme drought transitioning quickly to high / extreme rainfall, as well as plant disease agents such as Phytophthora (e.g. Phytophthora cinnamomii) are assumed to be the main causes.

A range of native and exotic species have been observed with dieback, including eucalypts, cypress-pine trees (*Thuja spp. and *Cupressus spp.) and exotic deciduous trees (e.g., *Fraxinus cv.).

However, little field data has been gathered.

 In 2025, the NSW Government and Wingecarribee Shire Council, commissioned a contractor to assess and report on eucalypt canopy dieback throughout the central and eastern parts of the Wingecarribee Shire.

This study focuses purely on eucalypts, primarily in natural bushland environments but also in modified farmland-paddock environments.This included patches of Southern Highlands Shale Woodlands.

2025 Wingecarribee Dieback Study(PDF, 2MB)

How to get involved
  • Sign up to a private land conservation program (e.g. Land for Wildlife)
  • Get involved in revegetation and restoration projects protecting SHSW. The Southern Highlands Landcare Network often deliver projects on private land. Some of these revegetation projects support SHSW.
  • Join Council's Bushcare program to help protect SHSW found within council managed reserves. 

Across the Wingecarribee Shire, eucalyptus trees have been exhibiting dieback, including species found within Southern Highlands Shale Woodlands. If you have SHSW on your property and are noticing dieback, get in contact with Council’s Environment and Sustainability Branch by phone on 4868 0888.

Related Information

Back to top