Flora of the Canadian Arctic Archipelago
English: Close-sheathed cotton-grass,
French: Linaigrette à anthères,
Inuktitut: Suputaujaq (Nunavik),
Cyperaceae, Sedge family.
Published in In Middendorff, Reise Nord. Ost. Sibir. 1(2) 3: 98, 1856.
Vegetative morphology. Plants 15–30(–45) cm high; perennial herbs; caespitose; loosely tufted in several tufts. Only fibrous roots present. Roots pallid-brown. Ground level or underground stems absent. Aerial stems erect; not filiform (0.6–1.0 mm in diameter). Leaves mainly basal; alternate; dying annually and non-persistent and marcescent. Petioles absent. Sheaths present; persisting; forming a conspicuous build-up at the base of the plant; brown (pallid); with the margins fused to the apex; glabrous; sheath collars absent. Ligules present; 0.5–1 mm long; membranous; glabrous. Ligule apices obtuse; entire. Leaves grass-like. Blades 60–200(–250) mm long, (0.4–)0.5–1(–1.2) mm wide, appressed to the stem or spreading, straight, linear (filiform, leaves bladeless sheaths), flat, veins parallel, midvein similar in size to other veins in the leaf. Blade adaxial surface glabrous (or minutely scaberulous seen at 40×). Blade abaxial surface glabrous. Blade margins glabrous; apices acuminate.
Reproductive morphology. Flowering stems solitary. Flowering stems triangular in cross section (in the upper half), or circular or oval in cross section (in the lower half). Flowering stems conspicuously taller than the leaves; with leaves; uppermost leaf arising above the middle of the stem (1–3 leafless sheaths distributed on culm). Leaf or reduced bract subtending the base of the inflorescence absent. Inflorescences spicate and head-like (a single spike); dense; ovate (broadly), or globose or sub-globose (erect, solitary spike); 1–2 cm long (2–3.5 cm long in fruit); 10–25(–40) mm wide. Pedicels absent. Inflorescence unispicate. Individual spike(s) erect. Bisexual spike(s) with empty bracts at the base (the lowest larger, opaque and 3-veined, 0.6–1 cm long). Terminal spike with both sexes in each floret. Floral scales black (ovate-lanceolate, 5–10 mm long, midrib not reaching the tip, usually 7 or more); with margins the same colour as the body of the scale; not reflexed (distinguishes this taxon from E. vaginatum s.l.); ovate, or lanceolate; 5–10 mm long; 1.5–4 mm wide; glabrous; apex acute. Perianth represented by bristles (the "cotton" of cotton grasses) (usually more than 8). Perianth bristles dull white (creamy white or tinged pale brown, about 20 mm long). Sepals modified (but not a pappus). Petals modified as bristles or perigynia. Stamens 3. Anthers splitting longitudinally. Anthers (0.5–)1–1.5(–2) mm long (narrowly elliptical). Ovary carpels 3; syncarpous. Styles 3. Stigmas per ovary 3. Placentation basal. Ovules per ovary 1. Fruit sessile; surrounded by a perianth persisting as bristles; dry; an achene; obovate; brown; 1.8–2.2(–2.7) mm long (0.5–1.2 mm wide); 0.9–1.1 mm wide; indehiscent. Achenes trigonous (apex minutely apiculate). Seeds 1.
Chromosome information. 2n = 58.
2n = 58. Löve and Löve (1944b, northern Europe); Löve and Ritchie (1966, northern Canada); Zhukova (1968, northeastern Asia); Krogulevich (1971, southern and northern Siberia; 1976, northern Siberia); Yurtsev and Zhukova (1978, eastern Chukotka); Löve (1981d, central Canada).
Ecology and habitat. Substrates: wet meadows, river terraces, tundra; imperfectly drained moist areas, seepage slopes; rocks, silt; with high organic content, peat; calcareous. A muskeg species that rarely extends far beyond tree line.
North American distribution. Alaska, Yukon, continental Northwest Territories, Nunavut Islands, continental Nunavut, northern Quebec, Labrador. Range in the Canadian Arctic Archipelago limited. Rare. Low Arctic. Arctic islands: Baffin (Clyde Inlet), Victoria, Southampton (Coral Harbour).
Northern hemisphere distribution. Circumboreal. Northern Fennoscandian, KaninPechora, Polar Ural Novaya Zemlya, YamalGydan, Taimyr Severnaya Zemlya, AnabarOlenyok, Kharaulakh, YanaKolyma, West Chukotka, Wrangel Island, South Chukotka, East Chukotka, West Alaska, North Alaska Yukon, Central Canada, Labrador Hudson Bay.
General notes. There is a new distribution record for this taxon occurring on Victoria Island since Porsild (1957).
Illustrations. • Herbarium specimen of delicate plant. Cespitose plants grow up to 70 cm high in continental North America. Rhizomes lacking. Note the bladeless leaf sheaths. Inflorescences are solitary spikes subtended by 7 or more blackish, empty scales. Perianth bristles are creamy white to pale brown. Inflorescences are conspicuously small in these specimens. Yukon. CAN 28205. • Scanned herbarium specimen (large plant). Inflorescences are solitary spikes subtended by 7 or more blackish, empty scales. Perianth bristles are creamy white to pale brown. Continental N.W.T., Great Bear Lake. CAN 199944. • Close-up of inflorescence from previous specimen. The inflorescences are solitary spikes subtended by 7 or more blackish, empty scales. Perianth bristles are creamy white to pale brown. Continental N.W.T., Great Bear Lake. CAN 199944. • Position of closed sheath. Plants with 1–3 bladeless sheaths distributed on the culm, the uppermost reaching above the middle. Nunavut, Baffin Island, Clyde River. CAN 204828. • Close-up of closed sheath. Apex of closed, bladeless, not inflated sheath responsible for the common name "Close-sheath cotton grass". Nunavut, Southampton Island. CAN 259365. • Close-up of inflorescence. Inflorescence empty scales 7 or more, ascending, blackish, ovate-lanceolate, 5–10 mm long, Nunavut, Baffin Island, Isortoq Fiord. CAN 295797. • Close-up of shedding inflorescence. Flowering head with empty grey scales at the base. The exposed rachis shows the position of attachment of each flower. There are unfertilised ovaries surrounded by perianth bristles towards the apex. N.W.T., Sitidgi Lake. CAN 535544. • Arctic Island Distribution.
This publication is available on the internet (posted May 2011) and on CD-ROM (published in 2007). These versions are identical in content, except that the errata page for CD-ROM is accessible on the main index page of the web version.
Recommended citation for the web-based version of this publication: Aiken, S.G., Dallwitz, M.J., Consaul, L.L., McJannet, C.L., Boles, R.L., Argus, G.W., Gillett, J.M., Scott, P.J., Elven, R., LeBlanc, M.C., Gillespie, L.J., Brysting, A.K., Solstad, H., and Harris, J.G. 2007. Flora of the Canadian Arctic Archipelago: Descriptions, Illustrations, Identification, and Information Retrieval. NRC Research Press, National Research Council of Canada, Ottawa. http://nature.ca/aaflora/data, accessed on DATE.
Recommended citation for the CD-ROM version of this publication: Aiken, S.G., Dallwitz, M.J., Consaul, L.L., McJannet, C.L., Boles, R.L., Argus, G.W., Gillett, J.M., Scott, P.J., Elven, R., LeBlanc, M.C., Gillespie, L.J., Brysting, A.K., Solstad, H., and Harris, J.G. 2007. Flora of the Canadian Arctic Archipelago: Descriptions, Illustrations, Identification, and Information Retrieval. [CD-ROM] NRC Research Press, National Research Council of Canada, Ottawa..