Throughout most of New South Wales native grasslands have been extensively cleared or modified, and now mainly occur as small remnants. Within the Namoi Catchment in northern NSW, grasslands remnants that occur on the Liverpool Plains and floodplain areas adjacent to the lower Namoi River are considered to be part of the community Natural grasslands on basalt and fine-textured alluvial plains of northern New South Wales (NSW) and southern Queensland that is listed as Critically Endangered under the Commonwealth Environment Protection and Biodiversity Conservation (EPBC) Act 1999.

Areas of native grassland in the Namoi Catchment that are likely to be remnants of the EPBC-listed grassland were mapped using a combination of extensive field validation, existing vegetation mapping, historic information from Parish and Portion plans, and various spatial layers. Extant and pre-European vegetation maps for the Namol Catchment were also updated during the mapping of the EPBC-listed grasslands.

The mapping produced by this project confirms that EPBC-listed grasslands have been extensively cleared, with about 5% of the pre-European extent remaining. About 8,900 hectares remain out of a probable pre-European extent of about 183,000 hectares. Most of the remnants are small and many occur on public land, particularly on Travelling Stock Routes. There are also good examples on private land, although no examples are known from conservation reserves in the Namoi Catchment. (VIS ID 3852)