The Wrekin & The Ercall

Site of Special Scientific Interest · 52.6714, -2.5492

Condition (Natural England)

Favourable (3)
UnitFeatureConditionArea (ha)Assessed
SJ629083 Favourable 216.74 2013-01-23
SJ641087 Favourable 216.74 2013-01-23
SJ644096 Favourable 73.06 2013-01-23

Geology & landscape

Geological Feature: Rock Outcrop · Mining / Industrial: Quarry · Geological Period: Cambrian, Precambrian · Rock Type: Gneiss, Quartzite, Sandstone

Landscape processes: Volcanic / Igneous

Birds & fish recorded

Birds

SpeciesSeason
redstart Breeding
sparrowhawk Breeding
woodcock Breeding

Description

Area, 283.3 ha. 700.2 ac. Description A prominent ridge which is of geological and biological importance. It forms the northeastern extremity of the South Shropshire Hills Area of Outstanding Natural Beauty. The area is extensively used for recreation. Biology The site is particularly valuable for the range of woodland vegetation which occurs at the northern end of the Wrekin and on the Ercall. Different types of woodland show a strong correlation with the underlying geology and with drainage. Much of the Ercall is occupied by sessile oak Quercus petraea woodland on thin, acidic soils overlying the Wrekin Quartzite. Other tree species present in this woodland type include holly Ilex aquifolium, downy birch Betula pubescens and rowan Sorbus aucuparia and the ground flora is dominated by species characteristic of acidic soils, such as wavy hair grass Deschampsia flexuosa, heather Calluna vulgaris, bilberry Vaccinium myrtillus, creeping soft grass Holcus mollis and the uncommon climbing fumitory Corydalis claviculata. Oak with hazel Corylus avellana occurs on slightly more fertile soils. On damper and more base rich soils, the woodland is characterised by ash Fraxinus excelsior and wych elm Ulmus glabra, although, as in many Shropshire woods, the elm is now mostly dead or dying. Where the ground is permanently wet, alder Alnus glutinosa is the dominant species. Ground flora species characteristic of the more fertile woodland vegetation types include ramsons Allium ursinum, yellow archangel Lamiastrum galeobdolon, woodruff Galium odoratum, dog’s mercury Mercurialis perennis and sanicle Sanicula europaea. Towards the summit of the Wrekin there are areas of heathland dominated by heather and acidic grassland with wavy hair grass, early hair grass Aira praecox, sheep’s sorrel Rumex acetosella and heath bedstraw Galium saxatile. There is a varied bird population. Breeding species include sparrowhawk Accipiter nisus, woodcock Scolopax rusticola, all three British woodpecker, seven species of warbler and redstart Phoenicurus phoenicurus. Geology The Wrekin ridge provides the best and most varied exposures of Uriconian rocks in England. This site is of great historical importance, as the place where the unconformable relationship between the Uriconian and Cambrian and the volcanic nature of the Uriconian, were first demonstrated. Recent radiometric dating of these rocks strongly suggests an early Cambrian, rather than Precambrian, age for this part of the Uriconian. The site also includes the small but significant outcrop of primrose Hill Gneiss, which resembles rocks found in the Malverns and has been interpreted as a rare relic, pre dating the Uriconian. The Uriconian has provided important evidence in attempts to reconstruct the early evolution of an ancient sea called the Iapetus Ocean and provides a valuable link with several other exposures of the early basement rocks in England, Wales and Canada. The Ercall Quarry contains the most instructive section available through the Wrekin Quartzite and lower part of the Lower Comley Sandstone Comley Series, Lower Cambrian. The conglomerates and massive quartzites of the Wrekin Quartzite contain a variety of sedimentary features which are a record of the submergence of the old Pre cambrian landmass by the sea in Cambrian times. The overlying greenish sandstones contain thin, nodular, lime rich beds and beds burrowed by marine animals. These rocks are of great importance in that they yield the oldest fossils apart from trails etc in this region. These are small shelly fossils and include brachiopods, hyolithellids and various, as yet, unclassified phosphatic forms. These provide the only links between the classic Lower Cambrian succession in Shropshire used as the British standard of reference and the equivalent strata in the English Midlands, the Malvern Hills, Scandinavia and Asia. Both units contain new and unusual assemblages of fossil traces. The site is of great importance in the interpretation of Lower Cambrian stratigraphy in Britain.

Species mentioned

English name
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Latin name
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IUCN / Red List Type Family
sparrowhawk Accipiter nisus NT (Breeding) bird-hawk falconidae
redstart Phoenicurus phoenicurus LC (Breeding) bird-robin muscicapidae
woodcock Scolopax rusticola LC (NonBreeding), VU (Breeding) bird-woodcock scolopacidae
early hair grass Aira praecox VU grass poaceae
wavy hair grass Deschampsia flexuosa Not listed in GB list grass poaceae
creeping soft grass Holcus mollis LC grass poaceae
ramson Allium ursinum LC herb liliaceae
corydalis Corydalis claviculata Not listed in GB list herb fumariaceae
woodruff Galium odoratum LC herb rubiaceae
heath bedstraw Galium saxatile LC herb rubiaceae
yellow archangel Lamiastrum galeobdolon LC herb lamiaceae
dog's mercury Mercurialis perennis LC herb euphorbiaceae
sheep's sorrel Rumex acetosella NT herb polygonaceae
sanicle Sanicula europaea LC herb apiaceae
billberry Vaccinium myrtillus LC shrub ericaceae
bell heather or ling Calluna vulgaris NT shrub dwarf ericaceae
alder Alnus glutinosa LC tree salicaceae
downy birch Betula pubescens LC tree betulaceae
hazel Corylus avellana LC tree corylaceae
ash Fraxinus excelsior LC tree oleaceae
holly Ilex aquifolium LC tree aquifoliaceae
sessile or durmast oak Quercus petraea LC tree fagaceae
rowan Sorbus aucuparia LC tree rosaceae
wych elm Ulmus glabra LC tree ulmaceae

Insects to look out for

These moths, butterflies and beetles are known to feed on plants recorded at this site, and carry a notable UK conservation status — but a host-plant being present doesn't mean the insect has actually been recorded here. Treat this as "worth watching for," not a confirmed sighting.

SpeciesStatusVia host-plant
Speckled footman
Coscinia cribraria
Critically Endangered Vaccinium myrtillus
Oak lutestring
Cymatophorina diluta
Endangered Quercus petraea
Shoulder-striped clover
Heliothis maritima
Endangered Calluna vulgaris
Scarce vapourer
Orgyia recens
Endangered Alnus glutinosa, Betula spp., Corylus avellana, Quercus spp., Ulmus spp.
Fiery clearwing
Pyropteron chrysidiformis
Endangered Rumex acetosella
White-letter hairstreak
Satyrium w-album
Endangered Ulmus glabra, Ulmus spp.
The sprawler
Asteroscopus sphinx
Vulnerable Betula spp., Corylus avellana, Fraxinus excelsior, Quercus spp., Ulmus spp.
Broom moth
Ceramica pisi
Vulnerable Betula spp., Calluna vulgaris, Rumex spp., Ulmus spp., Vaccinium myrtillus
Mottled umber
Erannis defoliaria
Vulnerable Betula spp., Corylus avellana, Quercus spp., Sorbus aucuparia, Ulmus spp., Vaccinium myrtillus
Satyr pug
Eupithecia satyrata
Vulnerable Calluna vulgaris, Galium spp.
Garden dart
Euxoa nigricans
Vulnerable Rumex spp.
Grayling
Hipparchia semele
Vulnerable Aira praecox
Bedstraw hawk-moth
Hyles gallii
Vulnerable Galium spp.
True lover's knot
Lycophotia porphyrea
Vulnerable Calluna vulgaris
The lackey
Malacosoma neustria
Vulnerable Corylus avellana, Quercus spp., Ulmus spp.
Pale brindled
Phigalia pilosaria
Vulnerable Alnus glutinosa, Betula pubescens, Corylus avellana, Fraxinus excelsior, Quercus spp., Ulmus glabra
Silver studded blue
Plebejus argus
Vulnerable Calluna vulgaris
Early moth
Theria primaria
Vulnerable Quercus spp., Vaccinium myrtillus
Pale eggar
Trichiura crataegi
Vulnerable Betula spp., Calluna vulgaris, Corylus avellana, Quercus spp., Vaccinium myrtillus
Oak hook-tip
Watsonalla binaria
Vulnerable Quercus petraea
Flounced chestnut
Agrochola helvola
Near Threatened Betula spp., Calluna vulgaris, Quercus spp., Ulmus spp., Vaccinium myrtillus
Beaded chestnut
Agrochola lychnidis
Near Threatened Rumex spp., Vaccinium myrtillus
Grey chi
Antitype chi
Near Threatened Rumex spp.
Garden tiger
Arctia caja
Near Threatened Rumex spp., Sorbus aucuparia
Dusky-lemon sallow
Cirrhia gilvago
Near Threatened Ulmus glabra
The sallow
Cirrhia icteritia
Near Threatened Rumex spp., Ulmus glabra
Rosy marsh moth
Coenophila subrosea
Near Threatened Vaccinium myrtillus
Dingy mocha
Cyclophora pendularia
Near Threatened Alnus glutinosa
Grey scalloped
Dyscia fagaria
Near Threatened Calluna vulgaris
Kentish glory
Endromis versicolora
Near Threatened Alnus glutinosa, Betula pubescens
Large thorn
Ennomos autumnaria
Near Threatened Alnus glutinosa, Betula spp., Corylus avellana, Quercus spp., Ulmus spp.
September thorn
Ennomos erosaria
Near Threatened Betula spp., Quercus spp.
Dusky thorn
Ennomos fuscantaria
Near Threatened Fraxinus excelsior
The Silurian
Eriopygodes imbecilla
Near Threatened Galium saxatile, Vaccinium myrtillus
Autumnal rustic
Eugnorisma glareosa
Near Threatened Betula spp., Calluna vulgaris, Galium spp., Rumex spp.
Double dart
Graphiphora augur
Near Threatened Betula spp., Quercus spp., Ulmus spp.
Weaver's wave
Idaea contiguaria
Near Threatened Calluna vulgaris
Clay fan-foot
Paracolax tristalis
Near Threatened Quercus spp.
Frosted green
Polyploca ridens
Near Threatened Quercus petraea
Dark-barred twin-spot carpet
Xanthorhoe ferrugata
Near Threatened Galium spp., Rumex spp.
Scotch burnet
Zygaena exulans
Near Threatened Vaccinium myrtillus
White prominent
Leucodonta bicoloria
Regionally Extinct Betula spp.

Host-plant data: Cook et al. (2025), Traits data for the butterflies and macro-moths of Great Britain and Ireland, 2024, UK Centre for Ecology & Hydrology / Butterfly Conservation; and Padovani et al. (2020), Database of Insects and their Food Plants (DBIF), UK Centre for Ecology & Hydrology (both Open Government Licence). Contains data supplied by UK Centre for Ecology & Hydrology.