Eriophorum scheuchzeri Hoppe
Bot. Taschenb. 1800: 104. 1800.
Eriophorum capitatum Torr.
Plants not caespitose (sometimes stems loosely clustered). Plants more than 15 cm high (usually); (10–)15–25(–40) cm high. Roots pallid-brown. Ground level or underground stems horizontal (that are thin); rhizomatous, or stoloniferous (not always present on herbarium specimens); elongate. Scales present (on stolons). Aerial stems erect; not filiform (1.0–2.0 mm in diameter); circular or oval in cross section; glabrous. Leaves mostly basal. Sheaths greyish brown (pallid, or yellowish brown); with the margins fused to the apex; glabrous. Ligules present; 0.5–1 mm long; transversely oblong; apices obtuse; entire. Blades herbaceous; straight; linear (caniculate at the base, triangular towards the tip); flat, or folded; glabrous. Blades adaxial surface glabrous.
Flowering stems conspicuously taller than the leaves; glabrous. Leaf or reduced bract closely associated with the base of the inflorescence absent. Inflorescence spicate; dense; oblong, or ovate (wider than higher); 1.5–3 cm long; 20–50 mm wide; a single spike. Individual spike(s) erect. Bisexual spike(s) with empty bracts at the base (2–6, sometimes enlarged with 3 veins, 0.4–1.2 cm long). Terminal spike with both sexes in each floret. Flowers sessile or subsessile. Floral scales black, or pale grey (ovate-lanceolate); with margins paler than body of scale; acute; 4–10(–14) mm long; 1–2 mm wide (empty bracts up to 6 mm wide); glabrous. Perianth represented by bristles; bristles silky white, or translucent (up to 30 mm long, often at right angles or deflexed). Anthers 0.5–1 mm long. Stigmas per style 3. Fruit 1.9–2.1 mm long; golden brown. Achenes trigonous.
Chromosome information. 2n = 60.
Distribution. Circumpolar. Arctic. Range in the Canadian Arctic Archipelago wide-spread. Common. Arctic Islands: Baffin, Ellesmere, Axel Heiberg, and Parry Islands (Melville), Banks, Victoria, Prince of Wales, Somerset, King William, and Southampton (and Ellef Ringnes).
Ecology and habitat. Substrate wet meadows, around the margins of ponds, depressions of low centre polygons, marshes, along streams (on raised terraces above braided channels), river terraces, lake shores; aquatic, or imperfectly drained; calcareous; sand, silt; with low organic content (bare sand), or with high organic content. Can form dense stands, almost monocultures. Also found in wet meadows with Carex, or in marshes as emergents with Pleuropogon sabinei. Commonly grazed by musk oxen.
Notes. Polunin (1940) commented that this species varies so much in the length of the anthers and the width of the white margin to the involucral scales that it is sometimes difficult to distinguish from specimens of the generally more slender E. chamissonis f. albidum. The shape of the head is apt to be misleading for it, and indeed the whole appearance of the pappus, may become changed after some days of exposure to wind, rain, and snow. Fernald (1905, p.82) gives the length of the anther as 1 mm in E. scheuchzeri and 1.5–3 mm in E. chamissonis and this allow us to separate the vast majority of specimens; but still there remain some that are intermediate, having anthers 1.2–1.5 mm long and seeming to unit the species or to indicate that they hybridize in the Canadian Arctic.
Illustrations. • Plants in habitat. Plants growing beside a pond. N.W.T., Banks Island, Sachs River delta, near Sachs Harbour, July 28, 1981. J.M. Gillett 18906, CAN. • Plants in habitat. Cotton-grass meadow. Nunavut, Baffin Island, Apex, CAN. • Plants in habitat. Dominant species in a small area of a sedge meadow. N.W.T., Banks Island, Aulavik National Park. 11 July, 1999. Susan Aiken 99–061, CAN. • Plants with inflorescences. Plants showing spaced inflorescences that are arising from rhizomes. N.W.T., Banks Island, Aulavik National Park. 11 July, 1999. Susan Aiken 99–061, CAN. • Close-up of inflorescence. Close-up of a single plant showing solitary spike. N.W.T., Banks Island, Sachs River delta, near Sachs Harbour, July 28, 1981. J.M. Gillett 18906, CAN. • Close-up of inflorescence. Close-up of a single spike approximately 2 cm high. N.W.T., Banks Island, Aulavik National Park. 11 July, 1999. Susan Aiken 99–061, CAN. • Close-up of inflorescence. Close-up of a single spike approximately 2 cm high with anthers less than 1 mm long caught in the bristles. N.W.T., Banks Island, Aulavik National Park. 11 July, 1999. Susan Aiken 99–061, CAN. • Close-up of plant. Note well developed rhizomes, peduncle with no leaves in the upper half, and a single inflorescence spike. Drawing by Mrs S. Bergh and Mrs L. Barstad based on a Svalvard: Oscar II Land: Kapp Boheman ved Pleuropogon, near Signalet J. Lid, 27 Aug. 1924. O. With permission of the Botanical Museum Univeristy of Oslo, Norway. • Arctic Island distribution.
Cite this publication as: Aiken, S.G., Boles, R.L., and Dallwitz, M.J. 1999 onwards. ‘Cyperaceae of the Canadian Arctic Archipelago: Descriptions, Illustrations, Identification, and Information Retrieval.’ Version: 6th November 2000. http://http://www.mun.ca/biology/delta/arcticf/. Dallwitz (1980) and Dallwitz, Paine and Zurcher (1993, 1995, 2000) should also be cited (see References).
