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

Scottish Natural Heritage Commissioned Report No. 090 (ROAME No. F02LD01)
species such as Narthecium ossifragum, Polygala serpyllifolia and Pedicularis sylvatica. Under the vascular
sward is a thin weft of bryophytes such as Calliergonella cuspidata, Hylocomium splendens, Sphagnum
fallax, Scleropodium purum and Lophocolea bidentata.
M27 Filipendula ulmaria-Angelica sylvestris tall-herb fen
This type of fen vegetation occurs around Achriabhach in Glen Nevis. It consists of tall, leafy swards of
Filipendula ulmaria, their stems topped in summer with the fragrant pale cream flowers, and an assemblage
of other species including Athyrium filix-femina, Cirsium palustre, Epilobium palustre, Juncus effusus, Galium
saxatile, Rumex acetosa, R. obtusifolius and Cardamine pratensis. There is little space for bryophytes under
the dense herbage. There are just a few wisps of Calliergonella cuspidata, Rhytidiadelphus squarrosus and
Lophocolea bidentata. This vegetation does not fit comfortably into any of the three sub-communities of M27.
Ecologically it is probably closest to the Urtica dioica-Vicia cracca sub-community M27b, a lowland
vegetation type of disturbed soils, as it occurs down-slope of the sheep fanks and farm track and is likely to
be flushed with nitrogen-rich water.
M31 Anthelia julacea-Sphagnum denticulatum spring
These small springs – generally though not always associated with snow-beds – are common at higher
altitudes in the survey area. Individually they are small, but on wet slopes where water seeps out diffusely
they can cover quite a lot of ground in total. They occur where the flow of water is slow or even intermittent,
and commonly fill the meltwater channels down-slope from places where snow lies late. They are very distinctive.
They consist of grey-green swollen mats and patches made up of dense masses of the tiny cylindrical shoots
of the liverwort Anthelia julacea. These mats are studded with the red-gold shoots of Sphagnum denticulatum,
the flat purplish shoots of Scapania undulata and with a variety of small plants such as Saxifraga stellaris,
Deschampsia cespitosa ssp. alpina, Gnaphalium supinum, Viola palustris, Huperzia selago, Carex bigelowii,
Epilobium anagallidifolium and Armeria maritima. Although usually found where the irrigating water is acid
as well as very cold, a few base-tolerant species can grow here, for example Cochlearia pyrenaica ssp.
alpina, Selaginella selaginoides, Carex saxatilis, Thalictrum alpinum and Persicaria vivipara. These springs
are also home to a number of scarce montane bryophytes such as Kiaeria starkei, Philonotis seriata,
Pohlia ludwigii, Polytrichum sexangulare, Pleurocladula albescens and Scapania uliginosa.
M32a Philonotis fontana-Saxifraga stellaris spring, Sphagnum denticulatum sub-community
This is the less species-rich and diverse of the two forms of this type of spring-head vegetation. It is the more
common of the two where the spring water emerges through acidic, peaty soil, but also occurs on richer
mineral soils where it forms mosaics with the Montia-Chrysosplenium sub-community (see below) as well as
with a range of other springs and mires. M32a consists of rich orange-gold spreads of the moss Sphagnum
denticulatum, patched with species such as Polytrichum commune, Philonotis fontana and Scapania undulata.
Rooted in the mats of mosses are plants such as Viola palustris, Saxifraga stellaris, Huperzia selago,
Juncus squarrosus and Eriophorum angustifolium, and grasses such as Deschampsia cespitosa, Agrostis canina
and Anthoxanthum odoratum. M32a springs are common throughout the study area. In the upper parts of
Coire a’ Mhadaidh and and Choire Lèitheith they form networks which make up a considerable proportion
of the total vegetation.
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