A vegetation community at risk

Status

The Pittwater Spotted Gum Forest was listed as an Endangered Ecological Community in the Sydney Basin Bioregion under the Threatened Species Conservation Act (1995) in late 1998. 

This means that all the native plants occurring as part of this vegetation community are protected including all the trees, shrubs, ferns, groundcovers, grasses and native vines.

In view of the small size of existing remnants, unless the circumstances and factors threatening its survival cease to operate, the NSW Scientific Committee is of the opinion that the Pittwater Spotted Gum Forest is likely to become extinct in nature.

All remaining remnants of Pittwater Spotted Gum Forest have conservation significance at a state level. 

Description

Pittwater Spotted Gum Forest occurs on shale-derived soils with high rainfall on lower hillslopes on the Barrenjoey Peninsula, Scotland Island and the western Pittwater foreshores. It is made up of both Coastal Dry Spotted Gum Forest and Coastal Moist Spotted Gum Forest.

This community is isolated from all other Spotted Gum forests - the nearest are at Liverpool and have a different genetic make-up. One of the wonders of Pittwater, Spotted Gums dominate the canopy.  They are easily identified by their straight grey and cream spotted trunks. 

Tree height is generally over 20 metres tall with individuals reaching 30 metres.  Associated trees include Grey Ironbark, Grey Gum, Bangalay, Smooth-barked Apple, Red Bloodwood, Broad-leaved White Mahogany, Turpentine, and Rough-barked Apple.

The structure of the community was originally open-forest and widespread but may now exist as woodland or remnant trees.  This community has been extensively cleared and is threatened by further clearing for housing, bushfire mitigation and onsite wastewater disposal. 

The canopy density in some areas has been reduced due to dieback. Remnants are also threatened by weed invasion especially Lantana camara, and by inappropriate fire regimes (no sooner than 12yrs or longer than 20yrs).

In the final determination for this community, Pittwater Spotted Gum Forest is characterised by the following assemblage of species. 

• Plant species list for Pittwater Spotted Gum Forest (Dry North/ West Facing Slopes and Ridges)
• Plant species list for Pittwater Spotted Gum Forest (Wet Gully and Southern Aspects)

Pittwater Council may also be able to provide free canopy tubestock for your property

Valuing Biodiversity

Spotted Gum Forest is structurally diverse and provides a great range of habitat niches for fauna.  As it is usually on better soils than other habitat types in Pittwater, its higher nutrient status means that it can support greater densities of fauna than other habitats.

As Spotted Gums flower mainly between May and September, they are a valuable winter food source.  Apart from the abundant nectar favoured by honeyeaters, lorikeets and possums and gliders, these trees also develop hollows.  Wattles also provide pollen and exudates (sap) consumed by gliders, including the threatened Squirrel Glider.

The thick groundcover, fallen limbs and occasional rock outcrops also provide shelter areas for species inhabiting the forest floor.  The regionally significant Long-nosed Bandicoot is probably the most obvious species favoured by this habitat feature.

The major remnants on the peninsula are mainly within Stapleton Park, and McKay, Crown of Newport, and Angophora  bushland reserves. Only tiny remnants on western Pittwater are included in the Ku-ring-gai Chase National Park.

Nurseries can supply local native plants

To preserve local genetic integrity, it is important to only plant species grown from seed collected in Pittwater.  Due to irregular availability of local seed, Spotted Gum seedlings may not always be available on demand.  Best to order in advance! 

For further information, or specific plantings list for your locality, please contact Natural Environment & Education Unit on 9970 1111

Pittwater Council may also be able to provide free canopy tubestock for your property

Natural Regeneration

Regeneration of Spotted Gum trees and associated understory plants relies on native seed stored on plants or in the top 10cm of intact natural soil to germinate when conditions are favourable. 

Natural regeneration provides a diversity of local native species usually more healthy, resilient to drought and fast growing with the advantage of local genotype.

To help natural regeneration, remove exotic lawn grasses and shrubs around base of remnant trees to dripline of canopy, allowing disturbed soil to remain open; mulch lightly.  Regularly weeding of site will encourage natural regeneration, as most natives like some top surface soil disturbance. 

Spotted Gum Forest is not adequately conserved in reserves with the majority occurring on private property. Protection of remnants on private land is vital to the future of our Spotted Gum Forest!  If no natural remnants remain, or soil has been filled, then planting is the next option to ensure the survival of these magnificent plants!

It is always best to seek advise from Council or a professional bush regenerator prior to carrying out any work!

Living in Spotted Gum Forest

• Value natives on your block and maintain a diverse community
• Save your natural soil profile, it contains dormant seeds that can regenerate naturally
• Let natural mulch reduce erosion and retain moisture
• Encourage regeneration on your block - is there room for a Spotted Gum or two?
• Identify, control and remove weeds
• Plant local natives associated with Spotted Gum Forest
• Limit the use of fertiliser - it encourages weeds

Updated: 24 Aug 2012