The Blue Gum High Forest of the Sydney Basin Bioregion is a wet sclerophyll forest found in the northern parts of Sydney, New South Wales, Australia. It has been classified as critically endangered, under the New South Wales government's Threatened Species Conservation Act 1995.[1] The principal canopy trees in this forest community are Sydney blue gum and blackbutt which are usually seen between 20 and 40 metres tall. 180 species of indigenous plants have been identified at Dalrymple-Hay Nature Reserve.

Blue Gum High Forest
Ecology
RealmAustralasia
BiomeTemperate broadleaf and mixed forests
Borders
Geography
CountryAustralia
Elevation70–180 metres (230–590 ft)
Coordinates33°44′12″S 151°9′15″E / 33.73667°S 151.15417°E / -33.73667; 151.15417
Climate typeHumid subtropical climate (Cfa)

Distribution

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The Blue Gum High Forest is restricted to the northern parts of Sydney, on soils based on shale with an annual rainfall over 1100 mm (43 in). Much of it grew on the ridge tops, roughly following the present day Pacific Highway from around Crows Nest up to Hornsby. Also it was recorded on soils based on the Mittagong Formation, volcanic diatremes and exposed shale lenses within the Hawkesbury Sandstone. Blue Gum High Forest grades into Turpentine-Ironbark Forest in drier areas of lower rainfall.

Remnants are found as far west as West Pennant Hills and Eastwood, though most of the few remaining areas are in suburbs such as Pymble, Turramurra and Wahroonga. Turiban Reserve in Wahroonga has particularly tall trees. Two of the larger forest remnants are Dalrymple-Hay Nature Reserve and Sheldon Forest. Around one percent of the original forest remains, and the current remnants amount to an area of 136 hectares (336 acres).[2][2]

Ecological status

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Due to fragmentation and the surrounding urban area, the forest remnants are constantly under threat from invasive plant species.[1] Bush regeneration programs have been put in place for many years. Significant species include Wandering Jew, Madeira vine, passionfruit vine, Chinese privet, ochna and camphor laurel.[3]

Fauna

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Sheldon Forest

Ring-tail possums, sugar gliders, brushtail possums and grey-headed flying foxes are common. There are occasional sightings of wallabies.[4]

Birds include rainbow lorikeet (Trichoglossus moluccanus), Australian king parrot (Alisterus scapularis), crimson rosella (Platycercus elegans), currawongs, variegated fairywren (Malurus lamberti), black-faced cuckoo-shrike (Coracina novaehollandiae), superb fairywren (Malurus cyaneus), powerful owl (Ninox strenua),[2] glossy black cockatoo (Calyptorhynchus lathami) and silvereyes.

The yellow-bellied sheathtail-bat (Saccolaimus flaviventris) is present though seldom seen.

Flora

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Selected plant species of Sydney Blue Gum High Forest
Common name Botanical name Approx. height Plantnet
Principal tree species
Sydney blue gum Eucalyptus saligna 20–40 metres details
Blackbutt Eucalyptus pilularis 25–45 metres details
Associated tree species
Sydney red gum Angophora costata 15–35 metres details
Grey gum Eucalyptus punctata 20–30 metres details
White mahogany Eucalyptus acmenoides 20–30 metres details
Red mahogany Eucalyptus resinifera 20–30 metres details
Turpentine Syncarpia glomulifera 20–30 metres details
Grey ironbark Eucalyptus paniculata 20–35 metres details
White stringybark Eucalyptus globoidea 15–30 metres details
Understorey tree species
Forest oak Allocasuarina torulosa 6–15 metres details
Sweet pittosporum Pittosporum undulatum to 15 metres details
Blueberry ash Elaeocarpus reticulatus to 15 metres details
Hickory Acacia implexa to 10 metres details
Lilly Pilly Acmena smithii to 10 metres details
Shrub species
Hairy clerodendrum Clerodendrum tomentosum to 10 metres details
Coffee bush Breynia oblongifolia to 3 metres details
Sydney golden wattle Acacia longifolia to 8 metres details
Myrtle wattle Acacia myrtifolia 0.3–3 metres details
Bleeding heart Homalanthus populifolius 0.5–5 metres details
Sweet bursaria Bursaria spinosa to 10 metres details
Gorse bitter-pea Daviesia ulicifolia to 2 metres details
Mock olive Notelaea venosa to 9 metres details
Common hop bush Dodonaea triquetra to 3 metres details
Cherry ballart Exocarpos cupressiformis to 8 metres details
Variable muttonwood Myrsine variabilis to 8 metres details
Yellow pittosporum Pittosporum revolutum to 3 metres details
Muttonwood Myrsine howittiana to 8 metres details
Narrow-leaved orangebark Denhamia silvestris to 4 metres details
Australian indigo Indigofera australis to 2.5 metres details
Tick bush Kunzea ambigua to 3.5 metres details
Herbs, grasses and ferns
Tussock grass Poa affinis details
False bracken Calochlaena dubia details
Maidenhair fern Adiantum aethiopicum details
Gristle fern Blechnum cartilagineum details
Sickle fern Pellaea falcata details
Pixie Caps Acianthus fornicatus details
Kidney weed Dichondra repens details
Lilac lily Schelhammera undulata details
Ivy Goodenia Goodenia hederacea details
Blady grass Imperata cylindrica details
Vines
Australian Clematis Clematis aristata details
Wombat berry Eustrephus latifolius details
Bearded tylophora Vincetoxicum barbatum (syn. Tylophora barbata) details
Scented milk vine Leichhardtia suaveolens (syn. Marsdenia suaveolens) details
Dusky coral pea Kennedia rubicunda details
Five leaf water vine Cissus hypoglauca details
Twining Glycine Glycine clandestina details
Wonga wonga vine Pandorea pandorana details
Other species

See also

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References

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  1. ^ a b "Sydney Blue Gum High Forest" (PDF). Nationally Threatened Species and Ecological Communities. Environment.gov.au. Archived from the original (PDF) on June 18, 2012. Retrieved May 16, 2012.
  2. ^ a b c "Blue Gum High Forest of the Sydney Basin Bioregion". Threatened species & ecological communities. Australian Government. Archived from the original on June 6, 2011. Retrieved May 17, 2012.
  3. ^ "Best practice guidelines for Blue Gum High Forest" (PDF). Retrieved May 23, 2012.
  4. ^ National Parks & Wildlife Service, info from a Field Officer