Machaerina rubiginosa

The robust grass-like sedge is rhizomatous and perennial, it typically grows to a height of 4 metres (13.1 ft) and a width of 2 m (6.6 ft). It blooms between August and March producing brown flowers.[5] It has rigid, terete and biconvex culms that are smooth and glabrous. The culms are 20 to 110 centimetres (0.7 to 3.6 ft) in length and 1 to 5 millimetres (0.04 to 0.20 in) in diameter. The narrow and erect inflorescence has an interrupted-oblong shape in outline forming dense clusters that are around 7 to 20 cm (2.8 to 7.9 in) long and with a diameter of 1 to 2.5 cm (0.39 to 0.98 in). After flowering an ellipsoid to obovoid shaped pale red-brown to bright orange coloured nut. The nut is smooth with a hispid apex with a length of 2.2 to 4 mm (0.09 to 0.16 in) and a diameter of 1.2 to 2 mm (0.05 to 0.08 in).[6]

It found in swamps and on the margins of lakes and streams along coastal areas in the Mid West, Wheatbelt, Peel, South West, Great Southern and Goldfields-Esperance regions where it grows in damp silty-sandy soils.[5] It is also found in Queensland, Victoria, New South Wales, South Australia, Tasmania and the Northern Territory.[6]

The upright foliage and spreading rhizomatous habit allow the plant to form large dense swards in wet areas. It can grow in nutrient poor soils in water up to a depth of around 50 centimetres (1.6 ft). The plant tends to grow taller in permanently damp areas and shorter in ephemeral environments. It is suitable for use in artificial wetlands.[7]