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

Scottish Natural Heritage Commissioned Report No. 090 (ROAME No. F02LD01)
mosses. The only common pleurocarpous moss in H18c is Hypnum jutlandicum. There is also a speckling
of lichens such as Cladonia portentosa and C. uncialis. H18c occurs on the south-facing slope of Sgurr a’
Bhuic and on a few north-facing slopes in the Grey Corries.
H19 Vaccinium myrtillus-Cladonia arbuscula heath
This montane heath is the Vaccinium-dominated counterpart of the Calluna-Cladonia heath H13. Like H13,
it is much more common in the eastern Highlands than it is in the west. It occurs in the Grey Corries on
Bein na Socaich and Stob Coire na Ceannain, on windswept ridges exposed to the south-west. Vaccinium
myrtillus, V. vitis-idaea, V. uliginosum and Empetrum nigrum ssp. hermaphroditum grow in a rich green,
prostrate mat less than 5cm high, dotted with the glaucous tufts of Carex bigelowii and with small species
such as Diphasiastrum alpinum, Huperzia selago, Deschampsia flexuosa, Festuca vivipara, Nardus stricta
and Galium saxatile. Over the ground is a pale carpet of lichens including Cladonia arbuscula, C. portentosa,
C. uncialis, C. furcata, C. rangiferina, Coelocaulon aculeatum, Ochrolechia frigida and Cetraria islandica.
There are also wisps and clumps of bryophytes such as Hypnum jutlandicum, Racomitrium lanuginosum,
Polytrichum alpinum and Ptilidium ciliare. Along with the other montane heaths, this is one of the habitats of
Loiselurea procumbens. On Beinn na Socaich H19 is home to Arctostaphylos alpinus in one of its few
stations south of the Great Glen. This vegetation does not fit clearly into any of the three sub-communities
of H19 described in the NVC.
H20a Vaccinium myrtillus-Racomitrium lanuginosum heath, Viola riviniana-Thymus polytrichus
sub-community
This is a montane form of Vaccinium heath, and is the sub-community most strongly associated with basic
soils. In the study area it is most widespread over the richer rocks of Meall Cumhann, Sgurr a’ Bhuic, the
upper west-facing slopes of Ben Nevis, the eastern side of Coire Guibhsachan and the Grey Corries. It has
a short, even sward of Vaccinium myrtillus and Empetrum nigrum ssp. hermaphroditum, dotted with V. vitisidaea,
V. uliginosum, Thymus polytrichus, Alchemilla alpina and, more locally, the uncommon montane shrub
Loiselurea procumbens. There is a sparse array of grasses such as Festuca vivipara, Deschampsia flexuosa
and Agrostis canina, and a freckling of small herbs such as Potentilla erecta, Galium saxatile and the more
montane Diphasiastrum alpinum and Carex bigelowii. These plants grow through a dense silvery weft of
Racomitrium lanuginosum, sprigged with R. fasciculare, Polytrichum alpinum and the lichen Cetraria islandica.
On the west-facing slopes of Ben Nevis, at about 1150m, the rare Veronica alpina and Cerastium cerastioides
grow near to the path in this type of vegetation.
H20b Vaccinium myrtillus-Racomitrium lanuginosum heath, Cetraria islandica sub-community
This is the most common form of mossy montane Vaccinium heath in the study area. It is extensive on the
steep, rocky upper slopes and on cols and ridges above about 750m. It is a community of bleak, windswept
and generally stony ground. The short, wind-pruned sward is made up of Vaccinium myrtillus, V. vitis-idaea,
V. uliginosum and Empetrum nigrum ssp. hermaphroditum, growing densely together through a silver-green
layer of Racomitrium lanuginosum. The sward is sprinkled with small montane plants such as Carex
bigelowii, Diphasiastrum alpinum, Loiselurea procumbens, Salix herbacea, Juncus trifidus, the moss
Polytrichum alpinum and the lichens Cetraria islandica and Ochrolechia frigida. There are also a few less
exacting species such as Festuca vivipara, Deschampsia flexuosa, Huperzia selago, Pleurozium schreberi
and Rhytidiadelphus loreus. The uncommon upland lichen Thamnolia vermicularis grows in this type of
vegetation on the Carn Dearg ridge.
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