Area: 1,111.9 hectares, 2,747.5 acres.

Nature Conservation Review Site. Incorporates SSSIs notified under the National Parks and Access to the Countryside Act, 1949 as Aylesbeare and Harpford Commons, Bicton and East Budleigh Commons, Colaton Raleigh and Woodbury Commons and Venn Ottery Common plus other areas included at this revision. In East Devon Area of Outstanding Natural Beauty. Parts are managed as non-statutory nature reserves. Mostly common land.

Description and Reasons for Notification:

This is the largest block of lowland heath in Devon. It is a nationally important representative of the inland Atlantic-climate, lowland heathlands of Britain and north-west Europe. A significant feature of the site is the diversity of heathland- associated communities, related to its large area and the range of substrate and topography. It also supports a wide range of birds and invertebrates.

The site overlies Triassic Bunter Pebblebeds, with some New Red Sandstone and Permian Marls, within an altitude range of 70 m to 150 m. The higher and drier areas are covered with heath dominated by heather Calluna vulgaris, bell heather Erica cinerea, western gorse Ulex gallii, bristle bent-grass Agrostis curtisii and purple moor-grass Molinia caerulea. Grasses and bracken Pteridium aquilinum are prevalent in places as are bramble Rubus fruticosus agg., and scrub with scattered pines Pinus spp. and birches Betula spp . 

A series of shallow valleys gives rise to distinct changes of vegetation. The dry heath gives way to wet heath with flushes on the valley sides, and to valley mire with patches of willow Salix spp. scrub mainly on the valley floors. Bell heather is replaced by cross-leaved heath Erica tetralix and characteristic species are common sedge Carex nigra, meadow thistle Cirsium dissectum, lousewort Pedicularis sylvatica, bogbean Menyanthes trifoliata, heath spotted orchid Dactylorhiza maculata , lesser butterfly orchid Platanthera bifolia and sharp-flowered rush Juncus acutiflorus. Other species associated with the wetter areas are bog asphodel Narthecium ossifragum, sundews Drosera spp., pale butterwort Pinguicula lusitanica, bog pimpernel Anagallis tenella, common cottongrass Eriophorum angustifolium and the club-moss Lycopodiella inundata

Mineral-rich flushes support tawny sedge C. hostiana, carnation sedge C. panicea, bog rush Schoenus nigricans and devils-bit scabious Succisa pratensis together with the brown mosses Scorpidium scorpioidesCampylium stellatum and Scorpidium revolvens

Over 70 breeding bird species have been recorded notably nightjar Caprimulgus europaeus, hobby Accipiter nisus and in most years Dartford warbler Sylvia undata. Among the 21 breeding dragonfly species are the small red damselfly Ceriagrion tenellum, southern damselfly Coenagrion mercuriale and the downy emerald dragonfly Cordulea aenea. The bog bush cricket Metrioptera brachyptera has been recorded here.