Treen Cliff

Site of Special Scientific Interest · 50.0444, -5.6385

Condition (Natural England)

Unfavourable Recovering (1)
UnitFeatureConditionArea (ha)Assessed
SW396223 Unfavourable Recovering 48.56 2010-08-12

Climate exposure

This is about exposure to a nationwide pressure this habitat type carries — not a verdict on this site's own management.

Coastal

Coastal habitats are exposed to sea-level rise and storm erosion. Where hard sea defences sit behind them, there's nowhere landward to retreat to — a squeeze that keeps compressing the habitat no matter how well it's managed.

Geology & landscape

Rock Type: Granite

Landscape processes: Coastal, Volcanic / Igneous

Description

Treen Cliff SSSI Description Treen Cliff is located on the South Cornwall coast some 10 kilometres southwest of Penzance. The site extends for around 1.5 kilometres from Porthcurno Beach in the west to Penberth Cove in the east. Several rare plant species including one Red Data Book* plant species, the western clover Trifolium occidentale occur on Treen Cliff. The site is also of particular importance for its maritime heathland. The mainly acidic brown earth soils are underlain by coarsely crystalline Armorican granite. This is cut by a large felsite dyke, exposed on Treen Cliff. The granite has weathered along widely spaced joint planes producing columnar cliffs, with tors and boulders on the slopes above. The main habitats are maritime heathland and grassland, heathland, scrub, flushes and deciduous woodland. Maritime heathland is dominated by heather Calluna vulgaris, bell heather Erica cinerea, and western gorse Ulex gallii. Maritime grassland occurs on the steeper cliff slopes and is dominated by red fescue Festuca rubra, with spring squill Scilla verna, wild carrot Daucus carota, kidney vetch Anthyllis vulneraria and sea plantain Plantago maritima. The nationally rare hare’s foot clover Trifolium arvense and western clover Trifolium occidentale also grow here, as well as the hairy bird’s foot trefoil Lotus subbiflorus, which is largely confined in Britain to the south-west coasts and bird’s-foot fenugreek Trifolium ornithopodioides. Scrub, dominated by gorse Ulex europaeus and blackthorn Prunus spinosa, covers large areas providing an important habitat for invertebrate and bird species. The gorse is parasitized by common dodder Cuscuta epithymum. A small area of woodland has developed on abandoned horticultural plots, dominated by elm Ulmus glabra and sycamore Acer pseudoplatanus. A number of wet flushes occur along the coast dominated by common reed Phragmites australis. A nationally rare weevil Anthocomus rufus occurs on the cliffs. This species has been found in only one other Cornish site. * The British Red Data Book lists vulnerable and endangered species.

Species mentioned

English name
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Latin name
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IUCN / Red List Type Family
no common name Anthocomus rufus LC beetle flower malachiidae
red fescue Festuca rubra LC grass poaceae
common reed Phragmites australis LC grass poaceae
lady's fingers (kidney vetch) Anthyllis vulneraria NT herb fabaceae
common dodder Cuscuta epithymum LC herb convolvulaceae
wild carrot Daucus carota LC herb apiaceae
hairy bird's-foot trefoil Lotus subbiflorus LC herb fabaceae
sea plantain Plantago maritima LC herb plantaginaceae
spring squill Scilla verna LC herb liliaceae
hare's foot clover Trifolium arvense VU herb fabaceae
western clover Trifolium occidentale LC herb fabaceae
bird's-foot clover Trifolium ornithopodioides LC herb fabaceae
blackthorn Prunus spinosa LC shrub rosaceae
gorse Ulex europaeus LC shrub leguminosae
western gorse Ulex gallii LC shrub leguminosae
bell heather or ling Calluna vulgaris NT shrub dwarf ericaceae
bell heather Erica cinerea NT shrub dwarf ericaceae
sycamore Acer pseudoplatanus Not listed in GB list tree aceraceae
wych elm Ulmus glabra LC tree ulmaceae

Plant communities

W20 — Montane scrub

Salix lapponum-Luzula sylvatica scrub

Salix arbuscula, Salix cinerea, Salix lapponum, Salix myrsinites, Salix phylicifolia, Salix reticulata, Empetrum nigrum, Calluna vulgaris, Salix lanata, Vaccinium myrtillus, Vaccinium uliginosum, Carex atrata, Carex bigelowii, Carex binervis, Carex flacca, Luzula multiflora, Luzula sylvatica, Huperzia selago, Selaginella selaginoides, Aulacomnium palustre, Mnium hornum, Philonotis fontana, Plagiomnium undulatum, Rhizomnium punctatum, Dicranum bonjeanii, Dicranum majus, Dicranum scoparium, Fissidens adianthoides, Racomitrium lanuginosum, Calliergonell cuspidatum, Ctenidium molluscum, Hylocomium splendens, Hypnum callichroum, Hypnum cupressiforme, Palustriella commutatum, Plagiothecium denticulatum, Plagiothecium undulatum, Pleurozium schreberi, Ptilium crista-castrensis, Rhytidiadelphus loreus, Rhytidiadelphus squarrosus, Rhytidiadelphus triquetrus, Sanionia uncinata, Scorpidium revolvens, Thuidium tamariscinum, Atrichum undulatum, Polytrichastrum alpinum, Sphagnum capillifolium, Sphagnum fallax, Sphagnum girgensohnii, Sphagnum palustre, Sphagnum russowii, Sphagnum squarrosum, Sphagnum subnitens, Sphagnum teres, Barbilophozia barbata, Chiloscyphus polyanthos, Diplophyllum albicans, Lophocolea bidentata, Plagiochila porelloides, Ptilidium ciliare, Scapania undulata, Cladonia squamosa, Peltigera canina, Angelica sylvestris, Caltha palustris, Hieraclium spp., Saussurea alpina, Solidago virgaurea, Campanula rotundifolia, Succisa pratensis, Valeriana officinalis, Rhodiola rosea, Vaccinium vitis-idaea, Thymus praecox, Epilobium anagallidifolium, Dactylorhiza viridis, Euphrasia officinalis, Rhinanthus minor, Oxalis acetosella, Oxyria digyna, Polygonum viviparum, Rumex acetosa, Anemone nemorosa, Ranunculus acris, Thalictrum alpinum, Alchemilla alpina, Alchemilla glabra, Filipendula ulmaria, Geum rivale, Galium boreale, Galium saxatile, Saxifraga aizoides, Saxifraga hypnoides, Saxifraga oppositifolia, Saxifraga stellaris, Viola riviniana, Agrostis canina, Agrostis capillaris, Anthoxanthum odoratum, Deschampsia cespitosa, Deschampsia flexuosa, Festuca ovina, Festuca rubra, Nardus stricta, Dryopteris dilatata, Phegopteris connectilis

W21 — Hedgerow scrub, Mixed scrub

Crataegus monogyna-Hedera helix scrub

Hedera helix, Salix cinerea, Acer pseudoplatanus, Ilex aquifolium, Betula pendula, Corylus avellana, Fagus sylvatica, Quercus robur, Fraxinus excelsior, Malus sylvestris, Sorbus aria, Taxus baccata, Ulmus glabra, Ulmus procera, Sambucus nigra, Viburnum lantana, Euonymus europaeus, Cornus sanguinea, Juniperus communis, Ligustrum vulgare, Clematis vitalba, Rhamnus cathartica, Crataegus laevigata, Crataegus monogyna, Prunus spinosa, Juncus effusus, Plagiomnium undulatum, Brachythecium rutabulum, Kindbergia praelonga, Rhynchostegium confertum, Tamus communis, Heracleum sphondylium, Torilis japonica, Arum maculatum, Arctium minus, Cirsium arvense, Lonicera periclymenum, Moehringia trinervia, Silene dioica, Stellaria graminea, Stellaria holostea, Stellaria media agg., Calystegia sepium, Mercurialis perennis, Geranium robertianum, Iris foetidissima, Glechoma hederacea, Lamium purpureum, Origanum vulgare, Stachys sylvatica, Teucrium scorodonia, Allium ursinum, Hyacinthoides non-scripta, Circaea lutetiana, Rumex sanguineus, Anemone nemorosa, Ranunculus repens, Fragaria vesca, Geum urbanum, Potentilla sterilis, Poterium sanguisorba, Rosa arvensis, Rosa canina, Rubia peregrina, Rubus fruticosus agg., Galium aparine, Urtica dioica, Viola riviniana, Anisantha sterilis, Arrhenatherum elatius, Brachypodium pinnatum, Brachypodium sylvaticum, Bromopsis erecta, Dactylis glomerata, Elytrigia repens, Holcus lanatus, Holcus mollis, Poa trivialis, Asplenium scolopendrium, Pteridium aquilinum, Dryopteris filix-mas

W22 — Hedgerow scrub, Mixed scrub

Prunus spinosa-Rubus fruticosus scrub

Hedera helix, Acer campestre, Corylus avellana, Ulex europaeus, Prunus spinosa, Plagiomnium undulatum, Brachythecium rutabulum, Eurhynchium striatum, Kindbergia praelonga, Thuidium tamariscinum, Atrichum undulatum, Lophocolea bidentata, Achillea millefolium, Cardamine flexuosa, Lonicera periclymenum, Moehringia trinervia, Silene dioica, Silene uniflora, Stellaria media agg., Mercurialis perennis, Geranium robertianum, Stachys sylvatica, Teucrium scorodonia, Hyacinthoides non-scripta, Oxalis acetosella, Digitalis purpurea, Plantago lanceolata, Veronica chamaedrys, Armeria maritima, Rumex acetosa, Filipendula ulmaria, Geum urbanum, Rosa canina, Rubus fruticosus agg., Rubus idaeus, Galium aparine, Urtica dioica, Viola riviniana, Agrostis capillaris, Brachypodium sylvaticum, Dactylis glomerata, Festuca rubra, Holcus lanatus, Holcus mollis, Poa trivialis, Asplenium scolopendrium, Pteridium aquilinum, Dryopteris borreri, Dryopteris filix-mas