6. Grassland, Sedgeland and Wetland

Natural grasslands are often associated with one or more of the woodland and sedge formations. They were probably of only small extent in the Hunter prior to white settlement, but have now been markedly increased by clearing and many exotic grasses have either been introduced or have invaded the areas. Tussock grasslands occur in the cold frost hollows on the Barrington Tops plateau, usually in association with mossy swamps. Sedgelands and wetlands are confined to the lower reaches of rivers, estuarine areas and behind coastal dune systems.

The small natural grasslands which are thought to have existed prior to white settlement in the eastern part of the Upper Hunter are mostly a Notodanthonia linkii - Austrostipa setacea community, while Notodanthonia linkii together with Dichanthium and Aristida species occur westward from the central valley. The latter are also components of the grasslands on the Merriwa plateau.

Grasslands on the Merriwa plateau

In the lower Hunter Paspalum and Sporobolus species predominate.

Tussock grasslands, of mostly Poa species, occur in the cold frost hollows on the Barrington Tops plateau, usually in association with mossy swamps, as at at Polblue Swamp. A bog in a grassy frost hollow on the basalts of Coolah Tops.

Barrington Tops

Polblue Swamp

Coolah Tops

Most swamps and sedgelands occurs on the water logged areas of the lower Hunter River and creeks draining into Lake Macquarie. Other small areas are scattered throughout the Valley on brackish and gravelly soils associated with watercourses and low lying depressions. Sedges are often associated with permanently waterlogged to perodically wet and damp areas mostly on sands or saline or acid soils. Swamp vegetation varies from 12 m tall Melaleuca Open-forests to woodlands with a shrub understory and dense sedge ground cover to shrublands with emergent taller shrubs and to sedgefields. Melaleuca quinquenervia is the dominant tree species in coastal wetlands, and M. nodosa, M. styphelioides and Casuarina glauca are common associates. Other trees include E. robusta and Livistona australis both of which may be locally dominant. Shrubs of Leptospermum, Callistemon, Banksia and Acacia also occur. Ferns, Cyperaceae and Restionaceae sedges and grasses are common.

Saltmarsh in the Hunter River estuary

A dense stand of Melaleuca quinquenervia with a fern and sedge ground cover in a coastal wetland south of Newcastle

A Phragmites wetland in the swales of the dunes supporting open-forest north of Newcastle