Rassal

General site character

• Bogs, Marshes, Water fringed vegetation, Fens (5%)
  
• Heath, Scrub, Maquis and Garrigue, Phygrana (25%)
  
• Alpine and sub-Alpine grassland (20%)
  
• Broad-leaved deciduous woodland (5%)
  
• Inland rocks, Screes, Sands, Permanent Snow and ice (45%)
  

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

• 7230 Alkaline fens

  Rassal in the north-west Highlands is representative of Alkaline fens developed from flushing through Durness limestone. The main type of fen are the more closed mires rich in Carices and other calcicolous small herbs (M10 Carex dioica – Pinguicula vulgaris mire). Open, stony flushes (M11 Carex demissa – Saxifraga aizoides mire) also occur, and are transitional in flora to 7240 Alpine pioneer formations of the Caricion bicoloris-atrofuscae. These are spring-fed mires and are numerous across the site. Black bog-rush Schoenus nigricans, broad-leaved cottongrass Eriophorum latifolium and the moss Scorpidium scorpioides are abundant locally in the fens.

• 8240 Limestone pavements  * Priority feature

  Rassal is one of four sites representing Limestone pavements on Cambro–Ordovician Durness limestone in north-west Scotland. In terms of the extent of the pavements, within Scotland Rassal is second only to Strath. Although the pavements are less well-developed structurally than on Strath, they occur up to a higher altitude (230-380 m) and have a more montane flora, similar to that at Inchnadamph. Notable northern and montane species occurring in the grikes include holly-fern Polystichum lonchitis (especially abundant), whortle-leaved willow Salix myrsinites, stone bramble Rubus saxatilis, green spleenwort Asplenium viride, globe-flower Trollius europaeus and rock sedge Carex rupestris. Stunted trees and shrubs, mostly downy birch Betula pubescens, rowan Sorbus aucuparia, ash Fraxinus excelsior and holly Ilex aquifolium are confined to rock crevices by browsing. Mountain avens Dryas octopetala occurs on thin soil on the clints and grades into 6170 Alpine and subalpine calcareous grasslands. Patches of S. myrsinites scrub are referable to 4080 Sub-Arctic Salix spp. scrub, while 9180 Tilio-Acerion forests of slopes, screes and ravines is also developed on part of the same exposure of limestone pavement. These are all Annex I habitats for which the site is also selected.

• 9180 Tilio-Acerion forests of slopes, screes and ravines  * Priority feature

  Rassal is unique in Scotland as the only large ash Fraxinus excelsior wood on limestone, and is important in representing Tilio-Acerion forest at the extreme north-western limit of its range. The site also encompasses the adjacent Allt Mór Gorge which contains further examples of the habitat. The wood is nationally important, particularly for its lichens, and the ground flora is species-rich with a number of plants of very restricted distribution, such as dark-red helleborine Epipactis atrorubens.

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

• 4080 Sub-Arctic Salix spp. scrub
• 6170 Alpine and subalpine calcareous grasslands
• 7220 Petrifying springs with tufa formation (Cratoneurion)  * Priority feature
• 8210 Calcareous rocky slopes with chasmophytic vegetation

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