Area: 31.99 hectares.
Description and Reasons for Notification:
Meddon Moor is a fragment of a formerly extensive moorland and mire system on the Carboniferous Culm Measures of North Cornwall. The unimproved “Culm grasslands” that occur here support a vegetation complex comprising grassland, heath, mire and fen communities, several of which are nationally restricted in distribution. The extent of such sites in Cornwall have decreased by at least 64% during the past six years and the remaining 137 hectares of unimproved Culm grassland represents a highly fragmented and decreasing resource.
Meddon Moor is the largest single fragment of remaining Culm grassland in Cornwall. This site is floristically diverse and supports a mosaic of characteristic Culm grassland community types.
Meddon Moor is the most northerly Culm grassland site in Cornwall, situated approximately 6 km north of Kilkhampton, on the Cornwall-Devon border, close to the watershed between the Rivers Tamar and Torridge. The site is underlain by sandstones of the Upper Carboniferous Culm Measures, which have weathered to produce cambic stagnohumic gley soils, often with a peaty surface horizon and impeded drainage.
The site supports examples of fen-meadow, rush pasture and mire that are typical of unimproved acidic grassland overlying the Culm Measures. Much of the site is dominated by purple moor-grass Molinia caerulea, with abundant meadow thistle Cirsium dissectum, devil’s- bit scabious Succisa pratensis, sharp-flowered rush Juncus acutiflorus and tormentil Potentilla erecta. Also occurring widely throughout the site are cross-leaved heath Erica tetralix, deergrass Trichophorum cespitosum, sedge species, in particular carnation sedge Carex panicea, bog asphodel Narthecium ossifragum, lousewort Pedicularis sylvatica and saw-wort Serratula tinctoria. Wetter hollows support a different association of species including marsh St John’s-wort Hypericum elodes, bog pimpernel Anagallis tenella, marsh pennywort Hydrocotyle vulgaris, lesser skullcap Scutellaria minor, and the nationally scarce wavy-leaved St. John’s-wort Hypericum undulatum. An additional species of interest which has a scattered distribution throughout the site is the petty whin Genista anglica.
The site supports a diverse bryophyte flora (mosses and liverworts) including Aulacomnium palustre, Campylium stellatum, Breutelia chrysocoma, Ordontoschisma sphagni, Hypnum jutlandicum and several Sphagnum species, such as Sphagnum tenellum. Also of interest is the presence of the moss Hookeria luscens amongst the bases of tussocks of purple moor-grass.
The site is bounded by streams to the north and east, with associated scrub, dominated by willow Salix sp. Habitat diversity is further increased by the presence of several small bog pools supporting species such as bog pondweed Potamogeton polygonifolius and common cottongrass Eriophorum angustifolium.