Tarn Moss

General site character

• Bogs, Marshes, Water fringed vegetation, Fens (95%)
  
• Humid grassland, Mesophile grassland (5%)
  

Annex I habitats that are a primary reason for selection of this site

• 7140 Transition mires and quaking bogs

  This basin mire has developed in a shallow, elongated hollow in acidic glacial drift. The mire communities are of special interest comprising areas of typical acid bog within a matrix of poor-fen. In comparison to other Cumbrian basin mires, Tarn Moss is remarkable in being almost entirely devoid of tree or scrub cover, as well as being little disturbed with no obvious signs of past peat-cutting.

  The poor-fen is the most extensive and best developed community at Tarn Moss. It is characterised by the dominance of Sphagnum bog-mosses and sedges Carex species, the latter including C. curta, C. echinata, C. rostrata and the very local northern species, C. magellanica. Other species include Hydrocotyle vulgaris, marsh cinquefoil Potentilla palustris, water horsetail Equisetum fluviatile, lesser bladderwort Utricularia minor, marsh violet Viola palustris, common marsh-bedstraw Galium palustre, lesser spearwort Ranunculus flammula, bog asphodel Narthecium ossifragum and cranberry Vaccinium oxycoccos. Small nuclei of more acid vegetation occur throughout the surface and in places merge to form larger patches of acid mire, dominated by heather Calluna vulgaris and cross-leaved heath Erica tetralix over bog mosses. Other species include bog-rosemary Andromeda polifolia and crowberry Empetrum nigrum.

Annex I habitats present as a qualifying feature, but not a primary reason for selection of this site

• Not Applicable

Annex II species that are a primary reason for selection of this site

• Not Applicable

Annex II species present as a qualifying feature, but not a primary reason for site selection

• Not Applicable