The Cooks River/Castlereagh Ironbark Forest (CRCIF) is a scattered, dry sclerophyll, open-forest to low woodland and scrubland which occurs predominantly in the Cumberland subregion of the Sydney basin bioregion, between Castlereagh and Holsworthy, as well as around the headwaters of the Cooks River. The Cooks River Clay Plain Scrub Forest is a component of this ecological community, though both belong to a larger occurring community called the Temperate Eucalyptus fibrosa/Melaleuca decora woodland.

Smithfield is a suburb of Sydney, in the state of New South Wales, Australia. Smithfield is located 31 kilometres (19 mi) west of the Sydney central business district, in the local government areas of the City of Fairfield and Cumberland Council. Located in the Greater Western Sydney region, the suburb is one of the largest in Fairfield City by area.