Holborn Moss

Holburn Moss is an example of a raised mire at the dry end of the range of variation, with its raised dome remaining in a semi-natural condition. 

Holburn Moss extends across 1,600 metres and the visible raised dome to the west of the site has peat depths exceeding 10 metres. Peat formation was estimated to have begun 7,000 - 7,500 years ago in an area that was previously open water and fen vegetation.

The moss itself is in a rain shadow created by the nearby Cheviot Hills and Southern Uplands of Scotland, meaning it is relatively dry. This is reflected in the vegetation, with heather Calluna vulgaris, hare's-tail cottongrass Eriophorum vaginatum and common cottongrass E. angustifolium dominating. Sphagnum cover is patchy.

The catchment slopes around the peat body include dry heathland, grassland with bracken and occasional scrub. Large numbers of greylag geese roost n Holburn Lake (2% of NW European population), leading to its designation as an SPA.