Irthing Gorge 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 ...

on the border between the counties of

Northumberland Northumberland ( ) is a ceremonial counties of England, ceremonial county in North East England, on the Anglo-Scottish border, border with Scotland. It is bordered by the North Sea to the east, Tyne and Wear and County Durham to the south, Cumb ...

and

Cumbria Cumbria ( ) is a ceremonial county in North West England. It borders the Scottish council areas of Dumfries and Galloway and Scottish Borders to the north, Northumberland and County Durham to the east, North Yorkshire to the south-east, Lancash ...

, in

England England is a Countries of the United Kingdom, country that is part of the United Kingdom. It is located on the island of Great Britain, of which it covers about 62%, and List of islands of England, more than 100 smaller adjacent islands. It ...

. It is located on the south-western boundary of

Northumberland National Park Northumberland National Park is the northernmost National Parks of England and Wales, national park in England. It covers an area of more than between the Scotland, Scottish border in the north to just south of Hadrian's Wall. The park lies en ...

where the

River Irthing The River Irthing is a river in Cumbria, England and a major tributary of the River Eden. The name is recorded as Ard or Arden in early references. For the first 15 miles of its course it defines the border between Northumberland and Cumbria. ...

flows near the village of

Gilsland Gilsland is a village in northern England about west of Hexham, and about east of Carlisle, which straddles the border between Cumbria and Northumberland. The village provides an amenity centre for visitors touring Hadrian's Wall and other f ...

. This protected has an exceptional mixture of habitats, including hillside woodland, seepage areas and bare rock. The gorge here cuts through

moorland Moorland or moor is a type of Habitat (ecology), habitat found in upland (geology), upland areas in temperate grasslands, savannas, and shrublands and the biomes of montane grasslands and shrublands, characterised by low-growing vegetation on So ...

Details

This protected area supports exceptional upland gorge woodland with

silver birch ''Betula pendula'', commonly known as silver birch, warty birch, European white birch, or East Asian white birch, is a species of tree in the family Betulaceae, native to Europe and parts of Asia, though in southern Europe, it is only found ...

and

downy birch ''Betula pubescens'' (syn. ''Betula alba''), commonly known as downy birch and also as moor birch, white birch, European white birch or hairy birch, is a species of deciduous tree, native and abundant throughout northern Europe and northern Asia ...

occurring on higher rockier ground.

Yew Yew is a common name given to various species of trees. It is most prominently given to any of various coniferous trees and shrubs in the genus '' Taxus'': * European yew or common yew (''Taxus baccata'') * Pacific yew or western yew ('' Taxus ...

trees occur on cliff ledges. Ash,

sessile oak ''Quercus petraea'', commonly known as the sessile oak, Welsh oak, Cornish oak, Irish oak or durmast oak, is a species of oak tree native to most of Europe and into Anatolia and Iran. The sessile oak is the national tree of Ireland, and an unof ...

wych elm ''Ulmus glabra'', the wych elm or Scots elm, has the widest range of the European elm species, from Ireland eastwards to the Ural Mountains, and from the Arctic Circle south to the mountains of the Peloponnese and Sicily, where the species reac ...

and

hazel Hazels are plants of the genus ''Corylus'' of deciduous trees and large shrubs native to the temperate Northern Hemisphere. The genus is usually placed in the birch family, Betulaceae,Germplasmgobills Information Network''Corylus''Rushforth, K ...

dominate the lower slopes.

Moss Mosses are small, non-vascular plant, non-vascular flowerless plants in the taxonomic phylum, division Bryophyta (, ) ''sensu stricto''. Bryophyta (''sensu lato'', Wilhelm Philippe Schimper, Schimp. 1879) may also refer to the parent group bryo ...

species include '' Mnium hornum'' and ''

Dicranum majus ''Dicranum majus'' is a species of moss belonging to the family Dicranaceae. It is native to the Northern Hemisphere The Northern Hemisphere is the half of Earth that is north of the equator. For other planets in the Solar System, north is de ...

''. Several

fern The ferns (Polypodiopsida or Polypodiophyta) are a group of vascular plants (plants with xylem and phloem) that reproduce via spores and have neither seeds nor flowers. They differ from mosses by being vascular, i.e., having specialized tissue ...

species have been recorded from rock faces including ''

Cystopteris fragilis ''Cystopteris fragilis'' is a species of perennial fern known by the common names brittle bladder-fern and common fragile fern. It can be found worldwide, generally in shady, moist areas. Description It has a short, black rootstock. The leaves ...

, Asplenium viride and Polystichum aculeatum''.

Lichen A lichen ( , ) is a hybrid colony (biology), colony of algae or cyanobacteria living symbiotically among hypha, filaments of multiple fungus species, along with yeasts and bacteria embedded in the cortex or "skin", in a mutualism (biology), m ...

species recorded here include ''Lepraria membranacea'' and ''Cystocoleus niger''. Plant species in damp seepage areas include limestone bedstraw, yellow saxifrage and the insectivorous plant called butterwort. The variegated horsetail has also been recorded here.

Red squirrel The red squirrel (''Sciurus vulgaris''), also called Eurasian red squirrel, is a species of tree squirrel in the genus ''Sciurus''. It is an arboreal and primarily herbivorous rodent and common throughout Eurasia. Taxonomy There have been ...

s and

badgers Badgers are medium-sized short-legged omnivores in the superfamily Musteloidea. Badgers are a polyphyletic rather than a natural taxonomic grouping, being united by their squat bodies and adaptions for fossorial activity rather than by their ...

have been recorded in this gorge. The project Red Squirrels United monitored

grey squirrels Gray squirrel or grey squirrel may refer to several species of squirrel indigenous to North America: *The eastern gray squirrel (''Sciurus carolinensis''), from the eastern United States and southeastern Canada; introduced into the United Kingdom, ...

and

red squirrel The red squirrel (''Sciurus vulgaris''), also called Eurasian red squirrel, is a species of tree squirrel in the genus ''Sciurus''. It is an arboreal and primarily herbivorous rodent and common throughout Eurasia. Taxonomy There have been ...

s in Irthing gorge between 2016 and 2020.

Geology

The exposed rocks of the gorge consist of thick beds of

sandstone Sandstone is a Clastic rock#Sedimentary clastic rocks, clastic sedimentary rock composed mainly of grain size, sand-sized (0.0625 to 2 mm) silicate mineral, silicate grains, Cementation (geology), cemented together by another mineral. Sand ...

with thinner bands of calcareous

shale Shale is a fine-grained, clastic sedimentary rock formed from mud that is a mix of flakes of Clay mineral, clay minerals (hydrous aluminium phyllosilicates, e.g., Kaolinite, kaolin, aluminium, Al2Silicon, Si2Oxygen, O5(hydroxide, OH)4) and tiny f ...

Land ownership and management

Part of the protected area is owned by the

Forestry Commission The Forestry Commission is a non-ministerial government department responsible for the management of publicly owned forests and the regulation of both public and private forestry in England. The Forestry Commission was previously also respons ...

.{{Cite web , date=2020-10-06 , title=Mapping the habitats of England’s ten largest institutional landowners , url=https://whoownsengland.org/2020/10/06/mapping-the-habitats-of-englands-ten-largest-institutional-landowners/ , access-date=2024-11-24 , website=Who owns England? , language=en The

Woodland Trust The Woodland Trust is the largest woodland conservation charity in the United Kingdom and is concerned with the creation, protection, and restoration of native woodland heritage. It has planted over 68 million trees since 1972. The Woodland Tru ...

also owns land in this protected area. In 2004 the Woodland Trust planted trees in 13ha of grassland in order to extend the woodland. Woodland management includes control of

Rhododendron ''Rhododendron'' (; : ''rhododendra'') is a very large genus of about 1,024 species of woody plants in the Ericaceae, heath family (Ericaceae). They can be either evergreen or deciduous. Most species are native to eastern Asia and the Himalayan ...

species.

References

Sites of Special Scientific Interest in Northumberland Sites of Special Scientific Interest in Cumbria Forests and woodlands of Northumberland Forests and woodlands of Cumbria