Magnesian limestone grassland is important because of its unique assemblages of plants and plant communities, including the Blue Moor-grass and Small Scabious community which is only found in east Durham and Tyne and Wear. Magnesian limestone grassland is recognised as a nationally scarce habitat as it is restricted to Magnesian Limestone rock and is included within Annex 1 of the EC Habitats and Species Directive.

Like other lowland calcareous grasslands, magnesian limestone grassland is important for its botanic and invertebrate interest. Magnesian limestone grassland supports many species which are nationally scarce or uncommon.

Habitats unique to the Durham Magnesian Limestone Natural Area, magnesian limestone grassland and the coastal denes have a rich variety of wildlife, supporting 13 nationally scarce plants and 84 nationally scarce invertebrates. Magnesian limestone grassland species include Northern Brown Argus, Glow-worm and Dark-red Helleborine. These species are all priority species in the Durham Biodiversity Action Plan (BAP).