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

Scottish Natural Heritage Commissioned Report No. 090 (ROAME No. F02LD01)
CG11a Festuca ovina-Agrostis capillaris-Alchemilla alpina grassland, Typical sub-community
CG11a is a dry form of herb-rich grassland which occurs on well-drained soils on the south-facing slopes
of Ben Nevis. The frothy yellow-green flowers of Alchemilla alpina make these swards conspicuous in
summer. A. alpina grows in dense mats in a turf of Festuca vivipara, Agrostis canina, Anthoxanthum
odoratum and Thymus polytrichus, together with species such as Potentilla erecta, Achillea millefolium,
Alchemilla glabra, Euphrasia officinalis and Lotus corniculatus. There are thin silvery mats of bryophytes
made up of Racomitrium lanuginosum, Hylocomium splendens and Rhytidiadelphus squarrosus.
CG11b Festuca ovina-Agrostis capillaris-Alchemilla alpina
Carex panicea sub-community
grassland, Carex pulicaris-
This, the damper form of Festuca-Agrostis-Alchemilla grassland, is common on the higher slopes of the study
area, especially on Meall Cumhann and on the eastern side of Coire Giubhsachan where the rocks are
base-rich. It is also widespread on Beinn na Socaich, and occurs in small patches elsewhere on the higher
slopes of the Grey Corries. The attractive, pale yellow-green, flowery sward consists of Festuca vivipara,
Agrostis canina, Nardus stricta, Anthoxanthum odoratum, Alchemilla alpina, Thymus polytrichus, Carex
panicea, C. pulicaris and C. caryophyllea, growing with base-tolerant plants such as Thalictrum alpinum,
Ranunculus acris, Plantago lanceolata, Selaginella selaginoides, Saussurea alpina and Alchemilla glabra
and species of damp ground such as Pinguicula vulgaris, Trollius europaeus, Succisa pratensis, Filipendula
ulmaria and Viola palustris. There are green sprigs of Vaccinium myrtillus. The bryophyte carpet is
more varied than it is in the drier CG11a, and consists of species such as Hylocomium splendens,
Racomitrium lanuginosum, Breutelia chrysocoma, Dicranum scoparium, Rhytidiadelphus loreus, R. triquetrus
and Scleropodium purum. CG11 occurs at higher altitudes than most examples of the Festuca-Agrostis-
Thymus grassland CG10 and clothes thin, stony soils, generally on steep slopes. Though much of it is
likely to be maintained by grazing, it is possible that some examples of this type of grassland are natural
climax vegetation.
CG12 Festuca ovina-Alchemilla alpina-Silene acaulis community
This type of vegetation, which occurs on Meall Cumhann, on the eastern side of Coire Giubhsachan, on
the Agaidh Garbh, in Coire a’ Mhadaidh and on Beinn na Socaich, is one of the more interesting upland
plant communities in the study area. It consists of a dense, emerald green turf of small or cushion-forming
base-tolerant plants. The most common is Silene acaulis, which grows with Alchemilla alpina, A. glabra,
Armeria maritima, Ranunculus acris, Thalictrum alpinum, Trollius europaeus, Persicaria vivipara, Selaginella
selaginoides, Saxifraga stellaris, S. oppositifolia, S. hypnoides, Silene acaulis, Thymus polytrichus, Angelica
sylvestris, Orchis mascula, Linum catharticum, Rhinanthus minor, Antennaria dioica, Filipendula ulmaria and
Geum rivale. Grasses and sedges spike sparsely through. The most common of these are Festuca vivipara,
Anthoxanthum odoratum, Agrostis canina, Luzula spicata, Carex pulicaris, C. panicea, C. bigelowii,
C. viridula ssp. oedocarpa and C. flacca. There is also a rich assemblage of bryophytes such as Ctenidium
molluscum, Hylocomium splendens, Rhytidiadelphus triquetrus, Neckera crispa, Tortella tortuosa, Ditrichum
gracile, Calliergon sarmentosum, Campylium stellatum and Herbertus stramineus. The CG12 in the study
area is home to a number of scarce species, such as Botrychium lunaria, Saussurea alpina, Tofieldia pusilla,
Luzula spicata and, on Meall Cumhann and the Agaidh Garbh, Salix lapponum, Cerastium alpinum and
C. arcticum.
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