Flora of the Canadian Arctic Archipelago
English: Arctic wood rush,
French: Luzule arctique,
Inuktitut: Iviit, ivisuka, ivitsuskaka.
Juncaceae, Rush family.
Published in Syst. Veg. 2: 111. 1825.
Type: Sweden: "Tagen wid Fjellet Jegna-apo-Tolle", 1821, leg. L.L. Laestadius, selected by Kirschner, Taxon 50: 1196. 2001. Lectotype: S.
Synonymy. Luzula campestris (L.) DC. var. (b) nivalis Laest., Kongl. Vetensk. Acad. Handl. 1822: 334. 1822.
Luzula arctica Blytt in Blytt and A.Blytt, Norges Fl. 1: 299. 1861.
Luzula nivalis f. nana Scholander, Skrifter om Svalbard og Ishavet, 62: 56. 1934.
Vegetative morphology. Plants (2.5–)5–20(–25) cm high; perennial herbs; caespitose (densely). Only fibrous roots present. Ground level or underground stems vertical (seen on older and more complete specimens). Aerial stems erect. Leaves present; mainly basal; alternate; marcescent (persisting for many years). Petioles absent. Sheaths present; brown, or straw-coloured pale yellow. Ligules absent. Leaves grass-like. Blades 40–120(–150) mm long, 1.5–3(–4) mm wide, straight, linear, flat (or involute towards the tips), veins parallel. Blade adaxial surface glabrous. Blade abaxial surface glabrous. Blade margins with non-glandular hairs (white, sparse); apices acuminate (often with a blunt and calloused tip).
Reproductive morphology. Flowering stems circular or oval in cross section. Flowering stems with leaves. Leaf or reduced bract subtending the base of the inflorescence present; conspicuous and leaf-like, or reduced, or scale-like (not extending beyond the inflorescence); shorter than the apex of the inflorescence (leafy); with calloused tip. Inflorescences head-like, or a spike of spikes (flowers in 2–7 compact clusters); dense; 0.5–3 cm long; 0.5–1.5 mm wide. Pedicels absent. Individual spike(s) erect, or ascending. Floral bracts apices lacerate (dentate; bracteoles deep brown, margins dentate or lacerate). Flowers per inflorescence 5–60; small. Sepals conventional (brown tepals); 3; free; 1.7–2.1 mm wide; brown (a deep shade with narrow, clear margins and apex, ovate or lanceolate); scarious. Calyx glabrous. Petals conventional (brown tepals); free; same length as the calyx; 3; brown (scarious); ovate, or lanceolate; unlobed; (1.7–)1.8–2(–2.1) mm long. Stamens 6. Anthers 0.4–0.6 mm long. Ovary superior; carpels 3; syncarpous. Styles 3; free. Stigmas per ovary 3. Ovules per ovary 3. Fruit sessile; with calyx persisting; dry; a capsule; ovoid (dark reddish to blackish, shining, spherical); brown; 1.5–2 mm long; 0.9–1.1 mm wide (intact capsules); not distinctly flattened; dehiscent. Seeds 3; 0.9–1.2 mm long; brown (translucent to clear. brown, broadly elliptic, with few entrangled hairs); surfaces smooth.
Chromosome information. 2n (4x) = 24. Nordenskiöld (1949, 1951, 1953); Knaben (1950, southern Norway); Holmen (1952, Greenland); Jakobsen, in Jørgensen et al. (1958, Greenland); Mosquin and Hayley (1966, northern Canada); Knaben and Engelskjøn (1967, northern Norway); Hedberg (1967, northern Canada); Johnson and Packer (1968, northwestern Alaska); Zhukova (1968, northeastern Asia); Packer and McPherson (1974, northern Alaska); Zhukova and Petrovsky (1976, 1980, western Chukotka); Zhukova et al. (1977, northeastern Asia); Yurtsev and Zhukova (1978, Eastern Chukotka); Dalgaard (1989, western Greenland).
Ploidy levels recorded 4x.
Ecology and habitat. Substrates: wet meadows, snow patches, around the margins of ponds, marshes, along streams, river terraces (and deltas), lakeshores (lowlands or slopes), tundra, slopes, ridges (on shallow beach ridges or swales; also on drumlin ridges); imperfectly drained moist areas, seepage slopes, dry (sites occasionally); gravel, sand, silt, clay, till, moss (in damp places); with low organic content (over sand on beach ridges), with high organic content; acidic (granite and acidic sandstone), or calcareous. Often locally abundant. Luzula nivalis occurs at a wide range of altitudes from the third tier of coastal beaches to alpine meadows as high as 800 m (2500') above sea level. On the slopes of shallow beach ridges, it is found in wet Carex, Eriophorum, or grassy meadows. On damp slopes, it grows with Ledum, Dryas, Salix arctica, and Luzula confusa. When it occurs together with L. confusa, it usually occupies the moister areas. In snow-bed communities, a common associate is Cassiope tetragona. In floodplains, it has been reported in mostly gravelly meadows with Carex and Salix.
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. Arctic islands: Baffin, Devon, Ellesmere, Axel Heiberg, Parry islands, Cornwallis, Banks, Victoria, Prince of Wales, Somerset, King William, Southampton, and Coats (and Prince Charles).
Northern hemisphere distribution. Circumpolar. KaninPechora, Svalbard Franz Joseph Land, 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, Ellesmere Land Peary Land, West Greenland, East Greenland.
General notes. Elven et al. (2003) discussed the use of the name L. arctica for this taxon. They noted that "a number of authors (Hultén 1968, Böcher et al. 1968, Porsild and Cody 1980, Novikov 1990) have considered L. nivalis to be conspecific with L. arctica, but some of them (Hultén 1968, Böcher et al. 1968) have used the name L. arctica, while the others (Porsild and Cody 1980...) [have used] the correct name L. nivalis." According to Chrtek and Krisa (1980), L. arctica and L. nivalis are not identical taxa. In 2005, Kirschner and Elven considered the taxa identical (Elven, personal communication) for the following reasons:
Elven et al. (2003) noted that Nordic and other European authors consider Læstadius' L. campestris var. nivalis as corresponding to current L. arctica. Elven et al (2003) stated "The type of Læstadius' var. nivalis ...clearly belongs to the same species as the type of L. arctica... and both belong to what we consider as L. arctica." According to Hylander (1945: 108–109; 1953: 186), and accepted by Swab (2000), Sprengel's application of the name 'nivalis' was different from the 'nivalis' of Læstadius and did not correspond to the Nordic and arctic plants; Sprengel's concept was of a central European plant and his description does not fit Læstadius' var. nivalis. Beurling (1853) also explicitly referred to the erroneous usage of Sprengel. If this is the case, Chrtek and Krisa (1980) are right in their comment, since the name 'nivalis' would have priority at varietal level but 'arctica' at species level. However, Sprengel's name is indeed based on L. campestris (L.) DC. var. nivalis Laest. Therefore, by priority, Luzula nivalis is considered the correct name, and a lectotypification is being published on a Laestadius collection in S (Kirschner, personal communication). Thus we use the name L. nivalis, although Brooks and Clemants (2000) use the name L. arctica.
Polunin (1940) noted that this is one of the most abundant, ubiquitous, and ecologically important of all arctic plants and that it varies considerably if sufficient material is examined. However, the extremes of variation of inflorescence form are linked by plentiful intermediate stages, and because of this and because they concern characters that are of little taxonomic importance elsewhere in the group, they seem hardly worth describing.
Polunin (1940) referenced specimens that appeared to him to be L. arctica × L. confusa hybrids. He noted that sheets labelled "L. hyperborea R. Br." frequently consist of a mixture of the two species, which is true of Robert Brown's type sheet in the British Museum, so that it seems best to discard this name altogether. Nobody else appears to have proposed a hybrid between these taxa that appear to be distantly related and without any hybridisation whatsoever.
Bell and Bliss (1978) estimated that the roots of L. nivalis (L. arctica) live 7–13 years.
Illustrations. • Calloused tip on leaf. Calloused tips of relatively flat leaves. This distinguishes this species from Luzula confusa. Aiken and LeBlanc 2004. No voucher. • Close-up of inflorescence. Inflorescence showing a dehisced capsule with few seeds (one per carpel). This distinguishes Luzula from Juncus which has many seeds per carpel. CAN 518286. • Close-up of plant. Basal leaves are relatively wide and rhizomes are absent. The inflorescence is tightly clustered. Drawing by Mrs. S. Bergh and Mrs. L. Barstad based on herbarium specimen. Svalvard, Weddel Jarlsberg Land, Recherche Bay, Ruby Point. 25 August, 1924. J. Lid. O-204032. With permission of the Botanical Museum, University of Oslo, Norway. • Close-up of inflorescences. Drawing by Mrs. S. Bergh and Mrs. L. Barstad based on herbarium specimen. Svalvard, Weddel Jarlsberg Land, Recherche Bay, Ruby Point. 25 August, 1924. J. Lid. O-204032. 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..