Gnaphalium norvegicum

Gnaphalium norvegicum Gunnerus (Asteraceae)

Highland cudweed, Cnàmh-lus Gàidhealach

Status in Britain: LOWER RISK - Nationally Scarce.               

Status in Europe: Not threatened.

G. norvegicum is a plant of gullies and stream gorges in the glens and corries of the central and western Highlands of Scotland. Colonies occur on sunlit slopes and ledges, almost invariably with an aspect between east and south and at an altitude over 700 metres. Plants grow on well-drained, enriched but acidic soils with an incomplete cover of vascular plants. Frequently, its sites are dominated visually by 'yellow composites'. Common associates are Alchemilla alpina, Anthoxanthum odoratum, Deschampsia cespitosa, Hieracium species (usually Sect. Alpina), Nardus stricta, Thymus polytrichus and Vaccinium myrtillus, although, in these open and enriched areas, a great range of ferns, herbs and grasses can occur. The great majority of colonies, and certainly all the small ones, are inaccessible to sheep and red deer and their extent appears to be restricted by grazing. It is intriguing, though, that two of the largest colonies are on open grazeable hillsides.

It is a perennial herb with a short woody rootstock, and plants can live for several years. Regeneration and spread of colonies is by seed, and the presence of small rosettes in most colonies confirms that this is happening. Colonies are mainly small and isolated, and G. norvegicum is very much a 'relict species' in Scotland. Immediately following glaciation it was presumably much more widespread (as it is in Norway today) but there is no evidence for this in the fossil record. Climatic warming, together with pressure from grazing animals, has led to the plant surviving now in just a few mountain areas. G. norvegicum is present in about 30 discrete colonies on about twelve mountains, and there are old records from a further four sites. Most colonies appear to consist of fewer than 100 individuals, but three hold hundreds of plants and one, thousands. However, counting plants is problematical in that most are sterile rosettes, which are difficult to spot. Confusion in the past with mountain forms of G. sylvaticum has meant that several old records have had to be rejected (for example, those from Perthshire and Caithness).

Sites of G. norvegicum are prone to snow avalanches and landslides, destabilising processes which maintain and enrich the open ground which the plant requires. Most colonies must be considered vulnerable because of their small size and unstable situation. One colony on Lochnagar consisted of 15-25 large plants and several small ones for many years, but one winter an avalanche swept most of the site away and in the following summer only six small rosettes could be found. Isolation of colonies and the distinct possibility of small colonies being extinguished by natural dynamic processes suggest that the range of the plant in Scotland is likely to be suffering steady attrition. However, the same processes may provide fresh ground for colonisation. Collecting has been heavy at only one site, Lochnagar. On that mountain the plant is now difficult to find, and the plants seen there pale into insignificance compared with the lush, multi-stemmed specimens residing in herbaria.

Colonies are under no threat from recreational pressures, other than from the occasional adventurous hill-walker or botanist scrambling in gullies. A significant reduction in grazing levels in the hills would benefit the plant, but other changes in land use are unlikely to have any impact. 

G. norvegicum occurs in the mountains of central Europe, arctic and sub-arctic Europe, Balkans, Caucasus, Greenland and north-eastern Canada. In Europe, it grows in meadows, heaths, open woods, rocky places and early-exposed grassy snow beds up to an altitude of 2,800 metres (Clapham, et al. 1962; Huxley 1967). In Norway it colonises bare stony ground beside roads and paths in the mountains, and its abundance comes as a pleasant surprise to visiting botanists from Britain.

A. G. Payne