C. norvegica is a perennial herb of wet, stony slopes, ledges and turf over basic rock and with base-rich run-off. All the sites have a mainly N.-facing aspect, and occur in places where snow lies late. Populations are usually quite small and of very limited extent. From 700 m at Corrie Fee (Angus) to 975 m on Beinn Heasgarnich (Mid Perth).
The distribution of C. norvegica is stable, but it has recently been discovered in a new locality in W. Perth.
Circumpolar Arctic-montane element.
Light (Ellenberg): 8
Moisture (Ellenberg): 7
Reaction (Ellenberg): 7
Nitrogen (Ellenberg): 2
Salt Tolerance (Ellenberg): 0
January Mean Temperature (Celsius): -0.8
July Mean Temperature (Celsius): 10.8
Annual Precipitation (mm): 1901
Count of 10km squares in Great Britain: 6
Count of 10km squares in Ireland: 0
Count of 10km squares in the Channel Isles: 0
RDB Species Accounts
Carex norvegica Retzius (Cyperaceae)
Close-headed alpine sedge, Seisg Lochlannach
Status in Britain: VULNERABLE.
Status in Europe: Not threatened.
C. norvegica is a sedge of wet rocky ledges, rocky slopes and grassy turf on, usually, the north or east faces of a very few mountains in Scotland, where snow lies late. It is confined to basic rock, often Dalradian mica-schist, at altitudes from 750 metres in Angus to 960 metres in mid-Perth. Its associated species are those typical of mica-schist; thus Alchemilla alpina, Festuca rubra, Persicaria vivipara, Saxifraga oppositifolia, Selaginella selaginoides and Thalictrum alpinum are constant associates, and Carex capillaris is usually present. In Angus it grows around rocks below montane willow scrub, and on rock ledges near Alopecurus borealis and Juncus castaneus. By contrast, in one of its mid-Perth sites it grows as a diminutive plant in a rich turf composed mainly of Armeria maritima, Minuartia sedoides, Saxifraga oppositifolia and Silene acaulis, and close to many other species including such local rarities as Carex atrofusca, C. saxatilis, Galium sterneri, Juncus biglumis, Poa alpina and Saxifraga nivalis.
C. norvegica is a shortly-rhizomatous perennial, flowering in June and July, and with ripe fruit in July and August.
It was first discovered in Angus in 1830 and is reliably known, for many years now, from two localities in mid-Perth, two in South Aberdeenshire and two neighbouring ones in Angus. Old records from Rum and the Uists are considered erroneous, though on northern Scandinavian coasts it does occur on blown shell-sand. Despite much hill botanising, there have been no recent confirmed additions. Some records in the last few years from the granite crags and summit plateaux of Lochnagar are undoubtedly misidentifications (perhaps chewed Carex bigelowii). A 1987 record from a mica-schist site near Ben Lui by an untraced recorder requires confirmation. A striking feature of the current populations is their restricted ground area; excluding the more spread-out Angus sites, areas are estimated at 25 and 200 square metres (South Aberdeenshire), and 20 and 120 square metres (mid-Perth). Monitoring of some populations has shown that numbers of flowering stems vary considerably from year to year, with typical maxima of 400 in Angus, 60 and 30 in south Aberdeenshire, and 150 in mid-Perth. Many plants are tiny. Whilst Angus specimens usually attain 10-20 cm in height, mid-Perth ones are usually under 5 cm, and a considerable proportion are merely 2-3 cm high. Notwithstanding, utricles always seem well developed.
The few sites, small area and stature and low flower numbers might suggest a very threatened species. However, there is no documented evidence of any overall decline. Current concerns centre more on the increasingly severe grazing by deer and sheep, and the disturbance of unstable or easily damaged habitats by visiting botanists.
Outside Scotland this arctic-alpine species occurs throughout the Scandinavian mountains and Iceland, in the central and eastern Alps, in arctic Siberia and North America, on the south coast of Greenland and ascending to 2,500 metres.
R. E. Thomas and J. Wright
PLANTATT - Attributes of British and Irish plants. (.zip 1455KB) This dataset was compiled and published in 2004, and last updated in November 2008. Download includes an Excel spreadsheet of the attributes, and a PDF explaining the background and nomenclature. Note that the PDF version is the booklet as published, whereas the Excel spreadsheet incorporates subsequent corrections. A hardcopy can be purchased from the Centre for Ecology and Hydrology.
Atlas text references
1986. Atlas of north European vascular plants north of the Tropic of Cancer. 3 vols.
1982. Sedges of the British Isles. Botanical Society of the British Isles Handbook no. 1, edn 2.
1965. Vergleichende Chorologie der zentraleuropäischen Flora. Volume 1. 2 vols.
1999. British Red Data Books. 1. Vascular plants, edn 3.