A survey of the vegetation of Ben Nevis - Scottish Natural Heritage

Scottish Natural Heritage Commissioned Report No. 090 (ROAME No. F02LD01)
H12bR Calluna vulgaris-Vaccinium myrtillus heath, Vaccinium vitis-idaea-Cladonia portentosa
sub-community, form with much Racomitrium lanuginosum
This is a more montane form of Calluna-Vaccinium heath. It has a mixed sward of C. vulgaris and Vaccinium
myrtillus with much V. vitis-idaea, Empetrum nigrum ssp. nigrum, Potentilla erecta, Galium saxatile and the
sedges Carex binervis and C. pilulifera. However, in this form of heath the characteristic mixed carpet of
pleurocarpous mosses is replaced by a grey-green sheet of Racomitrium lanuginosum, in which other species
such as Pleurozium schreberi, Hypnum jutlandicum and Rhytidiadelphus loreus grow as sparse shoots. It is
the counterpart of the Racomitrium sub-community of Calluna-Erica heath H10b, but with Vaccinium myrtillus
instead of Erica cinerea. The dwarf shrubs are pruned into a short and tight canopy by wind and exposure,
but do not grow prostrate as they do in the true montane heaths. There are patches of H12bR among H10b
and Trichophorum-Erica wet heath M15c on gentle slopes facing south-west and exposed to the prevailing
winds near the lower lip of Coire Eoghainn, at an altitude of 550–650m. It also occurs on the east-facing
side of the Carn Dearg ridge at 550–650m and in Coire na Ceannain at about 700m. This type of
vegetation has also been recorded on Beinn Eighe in Wester Ross (Averis & Averis 1998).
H12c Calluna vulgaris-Vaccinium myrtillus heath, Galium saxatile-Festuca ovina sub-community
We recorded this grassy type of Calluna-Vaccinium heath on cliff ledges on the eastern side of
Coire Giubhsachan and on the Bealach Cumhann. It has a pale, grassy sward in which Calluna vulgaris
and Vaccinium myrtillus grow with Festuca vivipara, Anthoxanthum odoratum, Nardus stricta, Deschampsia
flexuosa, Carex binervis and Juncus squarrosus. There is much Potentilla erecta and Galium saxatile.
Among the vascular plants is a mat of bryophytes such as Hypnum jutlandicum, Rhytidiadelphus squarrosus,
R. loreus, Hylocomium splendens and Pleurozium schreberi.
H13 Calluna vulgaris-Cladonia arbuscula heath
This type of montane heath is much more common in the colder and drier climate of the eastern and central
Highlands than it is in the west. We found it in several places in the Grey Corries part of the study area:
on Beinn na Socaich, in Coire Choimhlidh and on Beinn Bhàn and Stob Coire na Ceannain. It consists of
Calluna vulgaris, Vaccinium myrtillus, V. vitis-idaea, V. uliginosum and Empetrum nigrum ssp. hermaphroditum
growing in a tight mat less than 5cm deep, on gravelly, windswept moraines and ridges. The mat of shrubs
is spiked through by Carex bigelowii, C. pilulifera, Deschampsia flexuosa and Trichophorum cespitosum,
and dotted with a few herbs such as Potentilla erecta, Huperzia selago, Diphasiastrum alpinum and
Solidago virgaurea. Over the ground is a dense, grey-white carpet of lichens including Cladonia portentosa,
C. arbuscula, C. uncialis, C. rangiferina, C. furcata, C. coniocraea, Coelocaulon aculeatum, Cetraria islandica
and Ochrolechia frigida. This is patched with bryophytes such as Ptilidium ciliare, Hypnum jutlandicum,
Polytrichum alpinum and Racomitrium lanuginosum. The uncommon shrub Loiselurea procumbens grows in
this type of vegetation. The vegetation does not fit clearly into any of the three sub-communities of H13
described in the NVC.
H14 Calluna vulgaris-Racomitrium lanuginosum heath
This is the more western, oceanic form of montane Calluna heath. It is uncommon in the study area, but we
found small patches in Coire a’ Bhuic, on Tom na Sròine and in Coire Choille-rais. The sward is less than
5cm tall. Calluna vulgaris grows prostrate along the ground in a tight, red-grey mat through a dense
grey-green carpet of Racomitrium lanuginosum. A few small plants are able to grow in the sparse shelter
of the heather. The most common are Carex bigelowii, C. pilulifera, Empetrum nigrum ssp. hermaphroditum,
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