A rhizomatous perennial herb of base-poor, wet habitats, typically found in acid runnels, pools or semi-submerged Sphagnum lawns at pool edges. Formerly also lowland, its extant sites on Rannoch Moor are at c. 300 m (Mid Perth and Main Argyll).
All English sites for S. palustris were lost before 1900 due to drainage and eutrophication. The distribution in Scotland is stable; new sites have been found on Rannoch Moor recently due to detailed recording. It was discovered in Co. Offaly in 1951, but the original site was lost to peat extraction by 1960, and a nearby transplant did not survive.
Circumpolar Boreal-montane element, with a continental distribution in W. Europe.
Count of 10km squares in Great Britain: 14
Count of 10km squares in Ireland: 1
Count of 10km squares in the Channel Isles: 0
RDB Species Accounts
Scheuchzeria palustris L. (Scheuchzeriaceae)
Rannoch rush, Luachair Rainich, Brwynen Rannoch
Status in Britain: VULNERABLE.
Status in Europe: Not threatened.
S. palustris is now restricted to scattered localities on Rannoch Moor where it was first recorded in 1910 by Scarth. It occurs there in mid-Perth and Argyll but, oddly, has not been detected in the adjacent West Inverness part of the Moor. The altitude is about 300 metres. Its habitat is typically acid runnels, pools or very wet Sphagnum mire. It has few associates in runnels; the commonest associates elsewhere include Carex lasiocarpa, C. limosa, C. pauciflora, C. rostrata, Drosera rotundifolia, Eriophorum angustifolium, Menyanthes trifoliata, Molinia caerulea, Myrica gale, Narthecium ossifragum, Trichophorum cespitosum, Vaccinium oxycoccos and calcifugous Sphagnum species.
S. palustris is a perennial herb with scattered stems 10-20 cm tall spaced along a creeping rhizome. The leaves bear a conspicuous pore at the tip. Often the vast majority of stems are merely vegetative, and the lax 3-10 bisexual-flowered inflorescences are decidedly infrequent. Flowering occurs from June to August, and the species is wind-pollinated. However, there is perhaps little reproduction by seed, and propagation is likely to be mostly by its spreading rhizomes.
Many more sites for S. palustris have been found in recent years, and it is doubtful whether any have been lost this century. Although its sites on blanket mires are potentially threatened by afforestation, and to a lesser extent by burning in dry conditions and by agricultural improvement (drainage and fertilisation), virtually all sites lie within NNRs or SSSIs, and so are safeguarded to some degree. There are more than twenty locations for S. palustris known at present on the Moor or adjacent areas, some with several hundreds, if not thousands of plants or shoots. The shoots are grazed by red deer.
Last century, S. palustris is known to have occurred at four lowland sites in England, and at one site in the mid-Perth lowlands. The first record of the species in Britain was in 1807 from Leckby Carr, near Boroughbridge, and this was followed by discoveries in Shropshire, Cheshire and south-east Yorkshire, and at the White Myre, Methven, in mid-Perth. All sites were acidic mires. The loss of all the English sites before 1900 is attributed to drainage coupled with peat cutting. By contrast, the plant disappeared from Methven because of rapacious collecting, combined with the flooding of the mire, and nutrient enrichment from a gull colony there. In Ireland, it was discovered in Co. Offaly in 1951, but is no longer extant, despite attempts at transplantation to other sites (Curtis & McGough 1988). Further details of its distribution and ecology in Britain are to be found in Sledge (1949).
Elsewhere, S. palustris has a circumpolar distribution, mainly occurring between 40°N and 60°N, but is absent from Greenland, Iceland, much of continental North America, and a few parts of eastern Asia. The American plants are considered morphologically distinct, but are apparently similar ecologically. It seems to be in general decline over much of Europe, and is vulnerable in several countries.
R. A. H. Smith
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
1988. The Irish Red Data Book. 1. Vascular Plants.
1975. The history of the British Flora, edn 2.
1986. Atlas of north European vascular plants north of the Tropic of Cancer. 3 vols.
1965. Vergleichende Chorologie der zentraleuropäischen Flora. Volume 1. 2 vols.
1999. British Red Data Books. 1. Vascular plants, edn 3.