Area: 28.9 hectares.
Description and Reasons for Notification:
Southmoor Farm contains outstanding examples of several herb-rich grassland communities with a restricted distribution in Britain, together with scrub and woodland habitats.
The site, lying at an altitude of 125m, consists of 11 shallowly-sloping fields in a compact cluster on the Carboniferous slates and shales of the Culm Measures. The soils are clayey, acidic to neutral, and are poorly drained.
Most of the fields have acidic soils, supporting plant communities typical of the Culm Measures. These contain abundant purple moor-grassMolinia caerulea, meadow thistle Cirsium dissectum and devil’s-bit scabious Succisa pratensis, together with frequent glaucous, carnation,tawny and flea sedges Carex flacca, C. panicea, C. hostiana and C. pulicaris among many other species. A particularly notable and attractive feature of these fields is the occurrence of numerous heath spotted-orchids Dactylorhiza maculata and lesser butterfly-orchids Platanthera bifolia, the latter being nationally scarce. On better drained ground the sward contains much heather Calluna vulgaris, cross-leaved heath Erica tetralix and creeping willow Salix repens, while where it is wetter and most acidic, patches of bog mosses Sphagnum spp. occur with bog asphodel Narthecium ossifragum and common cotton-grass Eriophorum angustifolium.
The site in part has been traditionally managed for hay and supports a mesotrophic plant community not known elsewhere in Devon. It is characterised by abundant great burnet Sanguisorba officinalis, itself a local species in Devon, yellow rattle Rhinanthus minor and rushes Juncus spp. Other plant species present include oval sedge Carex ovalis, southern marsh-orchid Dactylorhiza praetermissa and ragged-robin Lychnis flos-cuculi.
At the lowest part of the site where the ground is waterlogged a marsh community has developed, with abundant hemlock water-dropwort Oenanthe crocata, wildaAngelica Angelica sylvestris and meadowsweet Filipendula ulmaria as well as rushes. On the edges of this marsh a good population of the nationally rare wavy St John’s-wort Hypericum undulatum occurs.
The site is enhanced by the broad scrub and woodland strips that occur between fields, often grading down gently to the open sward. Species of shrub and tree present include Pedunculate oak Quercus robur, alder Alnus glutinosa and aspen Populus tremula and the shrubs hazel Corylus avellana, spindle Euonymus europeus and eared willow Salix aurita. The local broad-leaved helleborine Epipactis helleborine is among the woodland herbs present.
Butterflies present include the scarce marsh fritillary Eurodryas aurinia and silver- washed fritillary Argynnis paphia. Breeding birds include willow tit Parus montanus, lesser whitethroat Sylvia curruca and reed bunting Emberiza schoenicula, and mammals include harvest mouse Micromys minutus and noctule bat Nycatlus noctula, the latter feeding over the fields.