Flora of the Canadian Arctic Archipelago


S.G. Aiken, M.J. Dallwitz, L.L. Consaul, C.L. McJannet, R.L. Boles, G.W. Argus, J.M. Gillett, P.J. Scott, R. Elven, M.C. LeBlanc, L.J. Gillespie, A.K. Brysting, H. Solstad, and J.G. Harris

Carex subspathacea Wormskjold, in Hornem.

English: Hoppner's sedge,

French: Carex subspathacé,

Inuktitut: Iviit, ivisuka, ivitsuskaka.

Cyperaceae, Sedge family.

Published in Fl. Dan. 9, 26: 6, t. 1530. 1816.

Type: Described from Greenland.

Synonymy. Carex salina Boott var. subspathacea (Wormskjold) Tuckerm., Enum Meth. 12: 1843.

Carex hoppneri Boott, in Hooker, Fl. Bot. Am. 2: 219. 1840.

Vegetative morphology. Plants 2–15 cm high; perennial herbs; not caespitose. Only fibrous roots present. Roots pallid-brown. Ground level or underground stems horizontal; rhizomatous; elongate (usually). Ground level or underground stems scales present. Aerial stems erect. Leaves present; mainly basal; alternate; dying annually and non-persistent. Petioles absent. Sheaths present; persisting; not forming a conspicuous build-up at the base of the plant; greyish brown (fronts lacking spots and veins, apex U-shaped); sheath collars absent. Ligules present. Leaves grass-like. Blades (10–)20–70(–100) mm long, 0.6–2.4 mm wide, straight, linear, involute (strongly; epistomic), veins parallel. Blade adaxial surface glabrous. Blade abaxial surface glabrous. Blade margins scabrous (scaberulous at the tip of the leaf only) or glabrous.

Reproductive morphology. Plants monoecious. Flowering stems triangular in cross section (obtusely angled). Flowering stems shorter than the leaves, or about as high as the leaves; with leaves. Leaf or reduced bract subtending the base of the inflorescence present; conspicuous and leaf-like; exceeding the inflorescence (1–3 mm wide, spathe-like at the base and enclosing the spike); 10–35 mm long; persistent; sheathless (the base of the blade may enclose the stem at the node but there is no sheath covering any part of the internode). Inflorescences a spike of spikes; 2–4 cm long; 5–12 mm wide. Pedicels glabrous. Cladoprophylls present. Inflorescence multispicate. Inflorescence 2–3 spikes (often hidden among the leaves). Individual spike(s) erect, or ascending. Terminal spike completely staminate (sometimes a second staminate spike, the 1–3 pistillate spikes 5–14 × 2–4 mm, few flowered and somewhat remote). Floral scales as long as the perigynium in fruit; brown, or black (sometimes purple tinged); with margins the same colour as the body of the scale; ovate (sometimes extended into an awn on the proximal scales at least); (2–)2.8–3.2(–3.6) mm long; (0.9–)1–1.6(–2) mm wide (wider than the perigynium, midvein reaching to the apex, one fifth to one half of the scale); glabrous; apex acute (rarely acuminate, or mucronate). Flowers unisexual. Staminate flowers conspicuous. Perianth represented by a perigynium. Stamens present (staminate flowers), or absent (pistillate flowers); 3. Anthers 1.2–1.5 mm long. Ovary superior; carpels 3; syncarpous. Perigynia sessile. Stipes 0.1–0.3 mm long. Styles 2; partially fused; slender, not extending beyond the beak, or slender, extending beyond the beak. Stigmas per ovary 2. Placentation basal. Ovules per ovary 1. Fruit surrounded by a perigynium. Perigynia fused to the apex except for a small aperture through which the style protrudes; broadly ovate (or narrowly ovate, ascending); 2.5–3(–3.6) mm long; 1.2–1.5(–1.8) mm wide; erect or ascending; straw-coloured, or green (sometimes with purple-brown spots on the apical half); leathery; surface dull; glabrous; papillose (near the beak); appearing veinless; apices beaked with a short beak (widely conic, 0.1–0.3 × 0.3–0.5 mm). Fruit sessile; dry; an achene; indehiscent. Achenes lenticular (slightly constricted on the margins, apex truncate to retruse, dull); not filling the upper part of the perigynia. Seeds 1.

Chromosome information. 2n = 78–83.

2n = 78–83.

2n = 78. Jørgensen et al. (1958, Greenland); Löve (1970a, Iceland); Yurtsev and Zhukova (1978, eastern Chukotka); Löve (1981d, northern Canada);

2n = about 78. Johnson and Packer (1968, northwestern Alaska); Packer and McPherson (1974, northern Alaska);

2n = 80. Zhukova and Tikhonova (1971, Chukotka); Zhukova and Petrovsky (1980, western Chukotka); Tanaka (1948);

2n = about 83. Engelskjøn (1979, northern Norway; 2n = 82, Bear Island);

2n = about 78, 80, 81, 82, 83. Cayouette and Morisset (1985, 1986, eastern Canada).

Two comparatively low-ploidy chromosome counts of 2n = 40 and 42 by Löve and Löve (1956, Iceland) and by Sørensen and Westergaard in Löve and Löve (1956) should be discounted, as they were not included by Löve and Löve (1975). Some of the Beringian counts (by Russian botanists and those of Johnson and Packer (1968)) might belong to subsp. Ramenskii, which has been confused with subsp. subspathacea in that region.

Ecology and habitat. Substrates: wet meadows, around the margins of ponds (on mud flats), marshes, river terraces (near the coast), seashores (in coastal lagoons, on beach ridges, and strand flats); imperfectly drained moist areas (usually brackish); gravel (occasionally), sand, silt (often salt encrusted); with high organic content, peat; halophytic. Along the seashore, this species is typically found just above the high tide line with Puccinellia phryganodes turf. On river terraces, common associates are Carex maritima, C. ursina, and Dupontia fisheri. It never occurs away from the influence of salt water.

North American distribution. Alaska, Yukon, Northwest Territories Islands, continental Northwest Territories, Nunavut Islands, continental Nunavut, northern Quebec, Labrador. Range in the Canadian Arctic Archipelago widespread. Common. Arctic islands: Baffin and Devon (literature record), Banks, Victoria, Somerset, King William, Southampton, and Coats (and Prince Charles Islands and Boothia Peninsula).

Northern hemisphere distribution. Circumpolar. Northern Iceland, Northern Fennoscandian, Kanin–Pechora, Svalbard – Franz Joseph Land, Polar Ural – Novaya Zemlya, Yamal–Gydan, Taimyr – Severnaya Zemlya, Anabar–Olenyok, Kharaulakh, Yana–Kolyma, West Chukotka, Wrangel Island, South Chukotka, East Chukotka, West Alaska, North Alaska – Yukon, Central Canada, Labrador – Hudson Bay, Ellesmere Land – Peary Land, West Greenland, East Greenland.

General notes. Carex subspathacea is a preferred forage species for lesser snow geese (Anser caerulescens) along with Puccinellia phryganodes. Gadallah and Jefferies (1995) analysed the nutrient content of these two species at La Perouse Bay, Manitoba, and found them to be higher than those of other salt marsh graminoids.

Seed set in this taxon is variable. This is a species that requires open ground to flower and set seeds. In areas with such conditions, that is, areas of very low covering and with low companion species, C. subspathacea will flower heavily and the seed set is good to very good, the achenes are well formed, but not fertile. In other areas where individual plants are crowded, most of the population seems sterile and vegetative (J. Cayouette, personal communication, March 2002).

In more boreal areas C. subspathacea is mainly an opportunist occupying gaps and other disturbed sites.

On Arctic islands, C. subspathacea has its own established position on the arctic seashores where it occupies a zone between Puccinellia phryganodes, closer to the sea, and a grass zone on higher ground.

Standley et al. (2002), in the Flora of North America treatment, noted that C. subspathacea "is evidently, with C. rufina, the smallest species of sect. Phacocystis. Larger plants with one to two staminate spikes and some bisexual spikes frequently occur in Ungava Bay, Hudson Bay, Northwest Territories, and Alaska, but their perigynium and achene characteristics are typical of those in C. subspathacea." (p. 382).

Among the several hybrids recognised, the ones that should be looked for in the Canadian Arctic Archipelago are Carex ×flavicans F. Nylander (= C. subspathacea × C. aquatilis), C. ×arctophila F. Nylander (= C. subspathacea × C. bigelowii), and C. ×sorensenii E. Lepage (= C. subspathacea × C. rariflora).

Illustrations. • Habitat. Dominant green plants in saline meadow. Nunavut, Baffin Island, Iqaluit. Aiken 97–036. CAN. • Habitat. Plants near the markers in a saline meadow with dark multispicate inflorescences. Nunavut, Southampton Island, Coral Harbour. Aiken and Brysting 01–073. CAN. • Rhizome and young inflorescence. Plant about 5 cm high showing rhizome with brown cladoprophylls. Young inflorescence subtended by spathe-like bract. Nunavut, Baffin Island, Iqaluit. Aiken and LeBlanc 04–016. CAN. • Close-up of inflorescence. Multispicate inflorescence subtended by a long, spathe-like leaf. Terminal spike staminate, lateral spikes pistillate. Nunavut, Baffin Island, Iqaluit. Aiken 97–036. CAN. • Close-up of plant. Flowering plants forming mat in salt marsh. The plants on the small raised tussocks have reached flowering stage first, being in a drier and warmer micro-habitat. Note the exposed anthers in the terminal spikes. Norway, Svalbard, Gipsvika. 18 July, 1985. Photograph by R. Elven. Voucher at TROM. • Close-up of inflorescence. Inflorescence at anthesis, terminal spikes male. Note the yellow pre-anthesis and the pale brown post-anthesis anthers. Norway, Troms, Lyngen, Svensby. 10 June, 1983. Photograph by R. Elven. • Close-up of inflorescence. Multispicate inflorescence subtended by a long leaf-like bract. Terminal spike staminate, lateral spikes pistillate with two stigmas per style. Drawing by Mrs. S. Bergh and Mrs. L. Barstad based on herbarium specimen Svalbard, Oscar II Land, Kapp Bohenam, ytse neset på strandi. 30 August, 1920. J. Lid. O. With permission of the Botanical Museum, University of Oslo, Norway. • 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.