CRITERION A: The site hold significant populations of rare fungal species which are of European or UK conservation concern. A site should be considered if it includes at least five species from: the provisional UK Red Data List (1992), UK Biodiversity Action Plan and/or Schedule 8 or the European Red Data List (A & B) and/or soecies of European Concern (Bern Convention proposals)

CRITERION B: The site has an exceptionally rich and well-recorded mycota in a UK context. A site should be considered if it has at least 500 recorded species.

CRITERION C: A site which is an outstanding example of a habitat type of known mycological importance.

CRIERION D: A nominated site which is considered to be important but for which further information is needed.