About Sclerolaena birchii (F.Muell.) Domin
Sclerolaena birchii, commonly known as galvanised burr, grows to around 1 m in both height and diameter. Its branches are hairy, and it bears obovate to narrow-obovate leaves that are 5 to 15 mm long. The leaves are shortly petiolate, flat and elongated. The fruiting perianth is hard, oriented obliquely, elliptic in shape, and measures 2 to 3 mm in length. It usually has 5 divergent spines: the 3 abaxial spines are longer, at 6 to 15 mm, while the 2 adaxial spines are usually 1 to 2 mm long. Persistent hair bases give the spine base a rough texture, and the seed is erect. This species can be found growing as isolated individuals or in dense stands, in coarse sandy soils or duplex soils. Galvanised burr often occurs near several vegetation communities, including bimble box, mulga and cypress pine. It is distributed throughout western New South Wales, and has also been recorded in Victoria and Queensland. In the Northern Territory, Sclerolaena birchii is classified as near threatened, while it is considered of least concern in both Queensland and Victoria.
