Area: 1758.3 hectares.
Description and Reasons for Notification:
This site contains extensive areas of heathland communities which are rare in Britain or confined largely to South West England and South Wales. The site is also important for the presence, range and transitions between habitats including upland heath, mires and grassland. At lower altitudes and in the coastal zone further important habitats occur including woodland and scrub, acidic and maritime grassland. Associated particularly with the coastal communities and woods are a wide range of nationally rare and scarce plants. A breeding colony of a nationally rare butterfly also occurs.
The site comprises four separate blocks (between Combe Martin and Minehead) centred on Trentishoe, Cosgate Hill, Countisbury and North Hill. The heaths all lie below 355 metres above sea level and the underlying rocks are mostly Hangman Grits which are hard sandstones of Devonian age.
Much of the site is vegetated by a dry type of western gorse – bristle bent Ulex gallii – Agrostis curtisii heathland which is very scarce elsewhere on Exmoor and nationally restricted to south-west England and Wales. It is dominated by mixtures of western gorse, bell heather Erica cinerea, heather Calluna vulgaris and bristle bent. The heath merges with grassland dominated by bristle bent on North Hill. The other major lowland heath type found here is the heather – western gorse community, which is also almost entirely restricted to Wales and south-west England. This community, dominated by heather, bell heather and western gorse often forms a mosaic, with a grassy turf of common bent Agrostis capillaris and sheep's fescue Festuca ovina. It also extends onto the exposed coastal slopes and cliff tops, where dwarf shrubs are severely wind-pruned and prosrtrate. The heath eventually grades into cliff-top grassland. Common dodder Cuscuta epithymum is abundant in places. Tall bushes of gorse Ulex europaeus form large stands mainly around the edges of the heathland. Bracken Pteridium aquilinum is common, but mainly restricted to combes and the lower slopes.
The coastal slopes have good examples of a community dominated by heather and bilberry Vaccinium myrtillus in which abundant bryophytes occur including Hypnum jutlandicum, Dicranum scoparium and Pleurozium schreberi. This typically upland community occurs here at altitudes as low as 250 metres because the slopes face North and are relatively cool. This community grades upslope and laterally to wet and lowland heath types, and also extends a long way down towards the shore where the cliff slopes are more gentle. In contrast, steep, dry south-facing slopes have heathland in which heather and bell heather are abundant, a community which is rare outside of Scotland and is very scarce on Exmoor.
In places damp western gorse – bristle bent heath merges with true wet heath, which occurs on flushed and ill-draining ground. A deergrass – cross leaved heath Trichophorum cespitosum – Erica tetralix community is widespread here and is dominated by mixtures of heather, cross-leaved heath and purple moor-grass Molinia caerulea. Also merging with this community are a few impoverished stands of wet heath with abundant cross-leaved heath and bog moss Sphagnum compactum. A few areas occur consisting of mosaics of a mire community dominated by purple moor-grass and tormentil Potentilla erecta, and areas dominated by rushes Juncus effusus/acutiflorus. Star sedge Carex echinata and bog moss Sphagnum fallax are common associated species in some areas and marsh bedstraw Galium palustre in others.
There are areas of semi-natural sessile oak Quercus petraea woodland, where downy birch Betula pubescens and silver birch B. pendula are also abundant. The shrub layer is sparse and the ground flora is dominated by Bracken, and on north facing slopes by great wood-rush Luzula sylvatica. Ash Fraxinus excelsior and alder Alnus glutinosa occur in narrow areas of woodland beside streams.
Around Hurlstone Point a very short seacliff grassland of the red fescue – thrift Festuca rubra – Armeria maritima type is found. It is dominated by red fescue, thrift and buck's-horn plantain Plantago coronopus with associated species including English stonecrop Sedum anglicum. Cliff top grassland of the red fescue – bluebell Hyacinthoides non-scripta type also occurs including species such as sea campion Silene maritima, lesser celandine Ranunculus ficaria, early purple orchid Orchis mascula and wild carrot Daucus carota.
There are two nationally rare, endemic whitebeam species which occur in the woodland areas namely Sorbus subcuneata and Sorbus vexans. Several nationally scarce plant species are found within this site; white mullein Verbascum lychnitis in its yellow form occurs in fields at the edge of the site, Cornish moneywort Sibthorpia europaea beside streams, rock stonecrop Sedum forsteranum on rocky seacliffs and sea storksbill Erodium maritinum, upright chickweed Moenchia erecta and bird's-foot clover Trifolium ornithopodioides all in areas of very short turf.
A nationally rare butterfly the high brown fritillary Argynnis adippe occurs on this site.
The coastal heaths support many of Exmoor's breeding wheatear Oenanthe oenanthe and strong populations of whinchat Saxicola rubetra and stonechat Saxicola torquata. Buzzard Buteo buteo and raven Corvus corax nest within the site and peregrine Falco peregrinus hunt over the cliffs. The mires provide nesting habitat for snipe and a few pairs of nightjar Caprimulgus europaeus nest on the woodland edges of North Hill.