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Area: 89.6 hectares. 

Other Information:

Amended at 1986 revision by extension and deletion. In Dartmoor National Park. Part owned by the National Trust. 

Description and Reasons for Notification:

The site is important for its ancient oak woodlands which support a rich lichen and moss flora including some rare and local species of lichen. 

Situated on the south-west of Dartmoor the site is subjected to a strong Atlantic climate. Within an altitude range of 250 to 800 metres, the woodlands cover the steep valley slopes around the confluence of the Rivers Meavy and Plym. The parent rocks are granite and other acid igneous types and are frequently exposed as clitter or faces. The soils are well drained and of a gritty, loamy nature with a humose surface horizon in places. 

The woodland canopy is dominated by pedunculate oak Quercus robur and is largely derived from former coppice. Sessile oak Q. petraea, beech Fagus sylvatica, ash Fraxinus excelsior and birch Betula spp. are present as co-dominants. Alder Alnus glutinosa occupies the banksides. The understorey is dominated by hazel Corylus avellana with holly Ilex aquifolium, rowan Sorbus aucuparia and hawthorn Crataegus monogyna being locally abundant; alder Buckthorn Frangula alnus is scattered throughout the woods. 

The ground flora, which is heavily grazed in places by sheep, has as its main constituents bilberry Vaccinium myrtillus, bramble Rubus fruticosus, creeping softgrass Holcus mollis and bent grasses Agrostis spp. honeysuckle Lonicera periclymenum, wood sorrel Oxalis acetosella, herb robert Geranium robertianum and heath bedstraw Galium saxatile are frequent, while patches of greater woodrush Luzula sylvatica occur along the river banks. Ferns are locally abundant, particularly on the moister, north facing slopes: typical species include male-fern Dryopteris filix-mas, broad buckler-fern D. dilatata, scaly male-fern D. affinis and hard fern Blechnum spicant. Bracken Pteridium aquilinum occurs throughout and forms dense stands along woodland edges. Tunbridge filmy-fern Hymenophyllum tunbridgense is well established, especially near the rivers. 

The rich lichen communities vary through the site according to the degree of exposure. Around the sheltered, lower valleys the community is characterised by lowland old forest species such as Arthonia didymaHaematomma elatinumPannaria pityreaSticta limbataParmelia reddenda and Thelotrema lepadinum. Locally rare species include Bryoria subcanaPorina coralloidea and Enterographa hutchinsiae. On higher ground a lichen flora occurs that is typical of exposed, upland oakwoods with a high rainfall. Parmelia laevigataP. taylorensisOchrolechia androgyna and Cladonia spp. are characteristically abundant, whilst Bryoria fuscescensSphaerophorus globosus and the rare, western Parmelia endochlora and Graphina ruiziana occur. 

There is a typical woodland breeding bird population, with such species as buzzard Buteo buteo, tawny owl Strix aluco, great spotted woodpecker Dendrocopus major and nuthatch Sitta europaea, whilst dipper Cinclus cinclus and grey wagtail Motacilla cinerea nest alongside the watercourses.