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Duck River Plants
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Duck River is
about 7 km long. It stretches from the catchment area of Regents Park in the south,
flowing north to its mouth
at the Parramatta River in Silverwater. It forms the local Council
boundary between Auburn in the east, and Parramatta in the west.
In February 1788, Governor
Phillip entered the mouth of the river while exploring the
Parramatta River. Seeing a group of wild ducks taking flight from a reed
bed, and thinking it might be a breeding ground for ducks, Governor
Phillip named the waterway Duck River. In 2009, the mouth of Duck River
still looks as Governor Phillip might have seen it, with Grey Mangroves Avicennia
marina, dominating a muddy tidal inlet.
Just upstream, we can still
find the Bullrushes; Typha domingensis and Typha orientalis, the
Common Reed Phragmites australis, several species of Juncus, the
Slender Water Pepper Persicaria decipiens, and also
Samphire Sarcocornia quinqueflora. (Note only indigenous species
mentioned.)
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Further
upstream, Duck River soils developed on the Wianamatta Shales, and belong to the Birrong Grouping. They are deep, usually greater than 250cm, and are described as yellow podsols, with yellow solodies found on
older alluvial terraces. The subsoils are often saline, with the overall soil profile subject to seasonal waterlogging.
The soils are highly erodable and of very low soil fertility (Benson & Howell 1990).
As Duck River
passes through Auburn, the topsoil is grey in colour, and of about
30-45 cm in depth, overlying a softer, more easily erodable subsoil. The subsoils are deep, tough and elastic clays which range in colour from red to yellow and yellow-white. The white clays developed on the exposed Minchinbury sandstones at Duck River were once highly prized by the local tile and
pipeworks.
As clay soils dry, they are prone to cracking, with larger fractures persisting for many years. The soils in the
Duck River area are highly fractured, a feature which becomes accentuated by erosion to give a raised block-like appearance to the surface.
In wet seasons, the soils quickly become saturated and most water
runs off the surface, rather than percolating into the subsoil.
The average
annual rainfall of nearby Parramatta is 900mm with most rain falling in
the Summer months.
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Botanical survey by Tony Price
in 1978
About 5 km
south from the mouth of Duck River, is Parramatta's "Duck River -
Wellington Road Reserve." This area of 11 hectares, being low lying
and next to the river, survived property speculation in the late 1800s,
and being cleared for agriculture. It was purchased by Parramatta
Council in 1846 and is extremely botanically valuable.
Between 1975 and
1978, Botanist Tony Price completed a comprehensive botanical survey of the Duck River -
Wellington Road Reserve as part of a Doctoral
Thesis. He has kindly assented to this information
being published. His survey gives us an extremely valuable picture of
the indigenous plants of the area, as this reserve has never had stock
or grazing animals on it.
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"There are six distinctive plant communities
within these 11 hectares: Grey Box/Broad-leaved Ironbark open-woodland., Ti-Tree and Paperback open-scrub and
open-heathland, areas of native grassland, riverine community along the watercourses, and a highly modified exotic grassland.
The native vegetation of
this Duck River Reserve is typical of the secondary regrowth which followed the clearing of the shale soils for agriculture in the 18th and early 19th centuries. By the mid-nineteenth century the secondary regrowth woodlands and forests had displaced most of the original open-forest which once dominated the eastern part of the Cumberland Plain.
The original vegetation was probably a tall woodland or open forest in which the dominant tree species were those of the drier parts of the Cumberland Plain. The dominant plant association would have been a Grey Box/Broad-leaved Ironbark Association with a number of the subordinant tree species and many of the understorey plants typical of moister environments.
The Red Mahoganies (E. resinifera) and Turpentines (Syncarpia glomulifera) from the wetter areas would have overtopped smaller
trees such as Cheese Tree (Glochidion ferdinandi), Breynia oblongifolia and Native Olive (Notelaea longifolla) - a pattern which still persists in isolated patches of remnant bushland.
Grey Box (Eucalyptus moluccana) and Broad-leaved Ironbark (E. fibrosa sap. fibrosa) are still the most common eucalypts in the reserve and in the south-eastern section have regenerated to form a woodland over a grassy understorey. Other species of Eucalyptus present include Woollybutt (E. longifolia), Red Mahogany (E. resinifera), Stringybark (E. globoidea), and Rough-barked Apple (Angophora floribunda). Cabbage Gum (E. amplifolla) grows in the gully towards Wellington Road and an unusual occurrence of Grey Gum (E. punctata) is found in the central-eastern part of the reserve associated with the outcropping of Minchinbury sandstone.
The south-western and central parts of the reserve are open-scrub and open-heathland. These characteristic regrowth areas are dominated by three species of Melaleuca, the Paperbarks Melaleuca decora and Melaleuca stypheloides, and M. nodosa, sometimes called Ti-tree or Teatree. These plant associations are generally richer in small shrubs and herb species than the surrounding woodlands. It seems likely that their widespread occurrence in the region is due to the early tree clearances and the frequent fires used by the settlers to manage the vegetation (Price 1979).
The bushland in the northern part of the reserve is more open in character with Ti-tree and Eucalyptus over a Kangaroo Grass
understorey. Other grasses, tiny herbs and ground orchids grow in the shelter of the grass tussocks while scattered pea flowers and other wildflowers provide a colorful show in early spring."
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"Encroaching upon the native grassland in both the southern and northern parts of the reserve are swards of exotic turf grass, mainly Kikuyu Grass
(Pennisetum clandestinum), which was
sown when the playing fields were established. Most of the exotica
within the Reserve, are found in the damper, nutrient-enriched soils along the watercourses. The beds of Duck River and its tributary creek have been used for the placement of sewerlines and stormwater drains and as a result have become weed-infested."
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Tony Price's survey
revealed 264 plant species. This list includes 50 species of grasses, 9
species of Acacias (wattles), 9 species of Eucalypts, 5 species of
Callistemons, 5 species of Melaleucas (paperbarks), one Geebung (Persoonia
linearis)
one species of Xanthorrhoea (resinosa), and several orchids, among
others. The species list is applicable for the riparian zone along
most of the length of Duck River, with the soil types as described.
Duck River species list - G A Price 1975
-1978.xls (24 kb)
Unfortunately,
not all 264 species remain in the reserve, mainly due to vandalism and
ignorance. For example, the last individual plant of Pomaderris lanigera
(pictured upper left) was burnt and destroyed by youths in 2007, when constructing bike jumps.
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If you live in
Sydney, we hope you will help sustain, and preserve, the botanical heritage for our younger generation.
Sydney has 2,000 indigenous plants, more than the whole of Great Britain
and Ireland. Why not design your gardens, using local plants ? Not only are Sydney plants beautiful, they require
minimal watering once established. Here is a list of indigenous vegetation by Sydney suburb if you need it:
Sydney vegetation list by suburb.xls (337 kb)
Animal and plant species all around the world are threatened by modern man's activities. While we encourage Sydney students to look after the plants of the Sydney botanical provenance, we hope students of all other botanical provenances round the world will look after their heritage.
This means that the students from around Duck River, or Hornsby, or indeed New Zealand, Indonesia, or any other area, each have a small, but different part of the world's species to look after.
While we should accept that everything is subject to change, we should not ignore, nor condone, the killing of entire species of plants and animals. Nor should we accept or encourage wanton environmental destruction.
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