The vegetation of the area

The dunes

Mobile dunes are stabilised by a distinct sequence of plant colonisation until eventually a community of plants dominated by trees and shrubs is formed. The major large species on the dunes include Banksia integrifolia, Acacia longifolia var. sophorae (Sydney Golden Wattle) and Leptospermum laevigatum (Coastal Tea Tree). The Eucalyptus botryoides (Bangalay) which used to be found in the area was almost all cut out during the Great Depression of the '30s for firewood.

Portion of a dune showing Banksia and Leptospermum.


View shows the west side of Connell Hill. In some areas bare sand can be seen. Because of the ease with which water can move through the sand soluble nutrients are quickly leached from the dunes and the levels of phosphorus and nitrogen in the soil are very low. Dune vegetation is characterised by adaptations to deal with water stress and low nutrient supply.

The three main shrubs of the dune vegetation grow by the road below Connell Hill.

 

Leptospermum laevigatum

Banksia integrifolia

Acacia longifolia
 

Features favouring survival duiring water stress

Sclerophyllous leaves. Drops leaves in times of water stress.  

Sclerophyllous leaf with silver hairs covering on back of leaf.

No leaves. Photosynthetic organs are phyllodes (flattened petioles).  

Features related to low nutrient supply

Forms mycorrhizae. 

Forms proteoid roots which facilitate nutrient uptake.

Has VA mycorrhizae and root nodules containing nitrogen fixing bacteria. 

Termite nest in dead Banksia tree

Termites play an important part in litter breakdown and nutrient recycling.
At the base of the dune, the water table comes close enough to the surface for a moist swale to be formed. This area has a more plentiful supply of plant nutrients leached from the upper parts of the dune and has a good water supply. Coastal vine forest vegetation used to occupy this area and included species such as Cupaniopsis anacardioides (Tuckeroo) and Syzygium sp, of which there are a few relic specimens. It has been disturbed by the road and is under severe attack by weed species such as Lantana camara and a wide variety of garden escapees.

Students and staff wait for the bus at the beginning of the excursion.

With the exception of the Banksia integrifolia trees to the right of the picture, most of the other plants shown are weed species.