Brignall Banks is a

Site of Special Scientific Interest A Site of Special Scientific Interest (SSSI) in Great Britain or an Area of Special Scientific Interest (ASSI) in the Isle of Man and Northern Ireland is a conservation designation denoting a protected area in the United Kingdom and Isle of ...

in the

Teesdale Teesdale is a dale, or valley, in Northern England. The dale is in the River Tees’s drainage basin, most water flows stem from or converge into said river, including the Skerne and Leven. Upper Teesdale, more commonly just Teesdale, falls ...

district of south-west

County Durham County Durham ( ), officially simply Durham,UK General Acts 1997 c. 23Lieutenancies Act 1997 Schedule 1(3). From legislation.gov.uk, retrieved 6 April 2022. is a ceremonial county in North East England.North East Assembly �About North East E ...

England England is a country that is part of the United Kingdom. It shares land borders with Wales to its west and Scotland to its north. The Irish Sea lies northwest and the Celtic Sea to the southwest. It is separated from continental Europe b ...

. It consists of a narrow belt of

woodland A woodland () is, in the broad sense, land covered with trees, or in a narrow sense, synonymous with wood (or in the U.S., the ''plurale tantum'' woods), a low-density forest forming open habitats with plenty of sunlight and limited shade (see ...

on the steep slopes of the valleys of the River Greta and its tributary, Gill Beck, just west of Brignall village and about 6 km south of

Barnard Castle Barnard Castle (, ) is a market town on the north bank of the River Tees, in County Durham, Northern England. The town is named after and built around a medieval castle ruin. The town's Bowes Museum's has an 18th-century Silver Swan automato ...

. It is one of the largest expanses of semi-natural woodland in North-east England; a number of scarce species are present, indicating that it is

ancient woodland In the United Kingdom, an ancient woodland is a woodland that has existed continuously since 1600 or before in England, Wales and Northern Ireland (or 1750 in Scotland). Planting of woodland was uncommon before those dates, so a wood present in 16 ...

. A varied lichen flora includes several species that are sensitive to air pollution and rare in County Durham, including some, such as '' Thelotrema lepadinum'' and ''

Graphis scripta ''Graphis scripta'' is a crustose lichen in the family Graphidaceae. It is commonly called script lichen, secret writing lichen, or similar names, because its growth pattern makes it looks like writing. '' Stigmidium microspilum'' and '' Arthon ...

'', that are indicator species for ancient woodland.

References

Sites of Special Scientific Interest in County Durham {{Durham-geo-stub