Flora of the Canadian Arctic Archipelago
English: Pendent grass,
French: Arctiphile fauve,
Inuktitut: Iviit, ivisuka, ivitsuskaka.
Poaceae, Grass family.
Published in Gram. Scand. 49. 1852. Incorrectly A. fulva (Trin.) Rupr. (Porsild 1964).
Type: U.S.A. Alaska: "Sinu Eschscholtz", leg. L.K.Chamisso. Holotype: LE-TRIN.
Synonymy. Poa fulva Trin., Mem. Acad. Imp. Sci. St. Petersburg Ser. 6, Sci. Math. 1: 378. 1830.
Colpodium fulvum (Trin.) Griseb., in Ledeb., Fl. Ross. 4: 385. 1852.
Colpodium fulvum var. effusum (Lange) Polunin, J. Bot. 76: 96. 1938.
Glyceria pendulina Laest. In Wahlenb. Fl. Suec., ed. 2: 1088. 1830.
Colpodium pendulinum (Laest.) Griseb. In Ledeb., Fl. Ross. 4: 386. 1852.
Colpodium fulvum f. aristatum Polunin, Bull. Natl. Mus. Canada 94 (Biol. Ser. 24): 78. 1940.
Colpodium fulvum var. effusum f. depauperatum (Nathorst) Polunin, Bull. Natl. Mus. Canada 94 (Biol. Ser. 24): 78. 1940.
Arctophila fulva subsp. pendulina (Laest.) A. and D. Löve, Bot. Not. (Lund.) 114: 49. 1961. Type described from northern Fennoscandia (Tzvelev 1976).
Arctophila fulva var. similis (Rupr.) Tzvelev, Zlaki SSSR, 2: 735. 1976.
Arctophila fulva subsp. similis (Rupr.) Tzvelev, Arkt. Fl. SSSR, 2: 169. 1974. Type: USSR, Insula Kolgujew interior 8 VII, Ruprecht, s.n.? (Holotype: LE, Tzvelev 1976).
Further synonymy in Tzvelev (1976).
Vegetative morphology. Plants 10–100(–150) cm high; perennial herbs. Only fibrous roots present. Ground level or underground stems horizontal, or vertical; rhizomatous (in some habitats, rhizomes grow vertically through very soft mud, producing numerous pale yellow roots at the nodes; when the plant grows in a colder climate or in a firm substrate, the rhizomes are shorter and oriented more towards the horizontal); elongate, or compact; 1–5 mm wide. Ground level or underground stems scales present; surfaces smooth; 10–40 mm long (disintegrating early); glabrous. Aerial stems erect (somewhat succulent). Leaves present; distributed along the stems; alternate; distinctly distichous (especially on non-flowering culms; the upper leaf blades conspicuously longer than the lower ones.); marcescent. Petioles absent. Sheaths present; with the margins fused only in the lower part; glabrous; sheath collars present. Ligules present; 1.2–5 mm long; membranous; glabrous; ovate-oblong. Ligule apices truncate; erose, or lacerate. Leaves grass-like. Blades 18–230 mm long, 2.5–6 mm wide, spreading, folded in bud, linear, flat, veins parallel, midvein conspicuously larger than the lateral veins or midvein similar in size to other veins in the leaf. Blade adaxial surface glabrous. Blade abaxial surface glabrous.
Reproductive morphology. Flowering stems circular or oval in cross section. Flowering stems with leaves; rooting at the lower nodes; culm nodes not exposed, or becoming exposed (rarely); culm nodes number visible 0–2. Inflorescences paniculate; diffuse; pyramidal; 4.5–16.5 cm long; 50–100 mm wide. Inflorescences main axis glabrous. Number of inflorescence branches at lowest node 1–5. Inflorescence primary branches 10–100 mm long; glabrous; with spreading secondary branches. Spikelets disarticulating above the glumes; ovate; 4–7.5 mm long; 1.5–5 mm wide. Florets per spikelet 3–5(–6). Two glumes present (glumes and lemmas rounded on the back.). First glume 0.95–1.1 × the length of the second glume; 0.6–0.65 × spikelet length; (1.8–)2.5–5 mm long; lanceolate; glabrous; margins glabrous; veins 1–3 (lateral veins faint); apex acute (or sub-obtuse). Second glume 0.4–0.9 × as long as the spikelet; almost as long as, or longer than, the lowest floret (but conspicuously shorter than the spikelet); 2.3–5.2 mm long. Second glume lanceolate. Second glume glabrous; veins 3. Rachilla not pronounced between the florets; extending beyond the uppermost floret; internode 0.9–1.1 mm long; internode glabrous. Callus differentiated (usually with 1–9 stiff hairs); hairs 0.2–0.5 mm long; hairs shorter than the floret. Lemma ovate, or lanceolate; 2.8–4.3 mm long; rounded on the back; surface dull; surface glabrous; veins 3 (sometimes with 2 faint, additional, lateral veins); apex rounded; apex entire, or erose and lacerate (with age); apex glabrous; awnless. Palea well developed; (1–)1.8–4 mm long; veins glabrous. Flowers bilaterally symmetrical (zygomorphic). Perianth represented by lodicules. Sepals modified (but not a pappus). Stamens 3. Anthers 1.4–2.5 mm long. Ovary superior; carpels 3; syncarpous. Ovaries glabrous. Styles 2. Placentation basal. Ovules per ovary 1. Fruit sessile; dry; a caryopsis; 1.8–2.2 mm long; indehiscent. Seeds 1.
Chromosome information. 2n = 42, or 96.
2n (6x) = 42. Flovik (1938, 1940, Svalbard); Sokolovskaya and Strelkova (1941, northern Russia, Konguev, 1960); Nygren, in Löve and Löve (1948, northern Europe); Sokolovskaya (1955); Jørgensen et al. (1958, Greenland); Löve and Solbrig (1965); Löve and Ritchie (1966, northern Canada); Hedberg (1967, northern Canada); Zhukova (1967a, 1969, northern Asia; 1980, southern Chukotka); Johnson and Packer (1968, northwestern Alaska); Knaben (1968, Alaska, 2n = 42 + 2B); Mulligan and Cody (1968a, northwestern Canada); Sokolovskaya (1968, northeastern Asia, Koryak; 1970, northeastern Russia); Zhukova et al. (1973, 1977, north and northeastern Asia; Zhukova and Tikhonova (1973, Chukotka); Packer and McPherson (1974, northern Alaska); Krogulevich (1976a, northern Siberia); Zhukova and Petrovsky (1976, western Chukotka); Cayouette and Blondeau (1997, northern Canada).
2n (9x) = 63. Zhukova and Petrovsky (1972, northeastern Asia).
Ploidy levels recorded 6x and 9x.
Taxon as an environmental indicator. Plant height varies dramatically with different microhabitats. Plants 1–1.5 m tall have been observed in the Mackenzie River delta and in drained lake basins of the Tuktoyaktuk Peninsula, N.W.T. In the High Arctic, plants may be less than 20 cm high and rarely flower. They often occur in similar habitats to Pleuropogon where they can be distinguished from vegetative plants of that species by the upper culm leaves that are longer than the lower ones.
Ecology and habitat. Substrates: wet meadows (of grass sedge mixtures), around the margins of ponds (and emergent in ponds), marshes, along streams (and in sandy stream beds), river terraces, lakeshores, tundra (wet); aquatic, imperfectly drained moist areas, moderately well-drained areas; rocks (sometimes on the rocky bottom of shallow ponds), sand (sometimes stony), silt (often); acidic, or calcareous (and marine deposits over acidic bedrock), or circum-neutral. Growing in, or at, the edge of shallow clear, tundra ponds, lakes, slow moving streams, or wetlands close to sea level, in water bodies where ice disappears early in the summer. Otherwise suitable habitats may be eliminated by the onshore thrusting of lake ice.
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. Uncommon. Low Arctic. Arctic islands: Baffin, Parry islands (Eglington, Melville and Prince Patrick), Banks, Victoria, Somerset, King William, Southampton, Coats (Prince Charles and Boothia Peninsula).
Northern hemisphere distribution. Circumpolar, or circumboreal (gaps in the North Atlantic areas). Northern Fennoscandian, 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, West Greenland.
General notes. Tzvelev (1976) reported that A. fulva is one of the best fodder plants and recommended it for introduction into cultivation in the northernmost regions of the USSR, "as it maintains a high nutritive value even at the fruiting stage and can be used as a pasture plant for deer even during the winter. The species is also good fodder for water birds."
Tzvelev (1976) noted that in the USSR the High Arctic populations of this species, with smaller general dimensions (10–30 cm tall), narrower laminas, and fewer spikelets, are separated as subspecies similis (Rupr.) Tzvelev but are rather only a variety, var. similis (Rupr.) Tzvelev, to which not only the type of Poa similis but also the type of Poa remotiflora belong. No attempt to distinguish taxa within plants of the genus occurring in North America has been made, although considerable phenotypic plasticity, apparently often related to microclimate, has been observed.
Tzvelev (1976) noted that "the affinity of the genera Arctophila and Dupontia is confirmed by the existence of the sterile hybrid × Arctodupontia scleroclada (Rupr.) Tzvelev, 1973, Novosti Sist. Vyssh. Rast. 10: 91 (= Poa scleroclada Rupr...) described from the Malaya Zemlya tundra...but recently also found on the Chukotsk Peninsula". On the basis of spikelet structure, it occupies an intermediate position between the parental genera. The intergeneric hybrid has not been reported from North America, but there are places where the two genera occur together and where the possibility of hybrid plants should be investigated, for example, on the Tuktoyaktuk Peninsula and Richards Island at the mouth of the Mackenzie River. However, in Feb. 1999, in a survey of candidate specimens at LE, the only record of the hybrid was the type collection (LE) and it is a questionable specimen. All other specimens of Arctodupontia from the Chukotsk Peninsula were re-determined as Arctophila fulva (R. Elven, personal communication, 1999). However, hybrid populations between Arctophila and Dupontia have recently been confirmed (also by molecular means) from Svalbard, Brysting and Elven (2005).
Ovenden (1986) found Arctophila fulva was an early colonising species on the lake bed of Illisarvik, the site of a thermokarst lake that was artificially drained in August 1978.
Elven et al. (2003) indicated that the impressive infraspecific variation is probably too insufficiently known to allow for the recognition of any subspecific taxa.
Aiken and Buck (2002) described aquatic leaves and vegetative proliferation in this taxon (additional images in the image library). They observed re-growth from apparently dead, previous season's straw that had overwintered in the Arctic. Observations on transplanted material and field observations documented that new shoots grew from the apex, and nodes of the previous season's stems. Strong underground rhizomes, and roots developed, resulting in propagules able to develop into new plants. The previous season's straw that regenerates is probably detached by animals mid-season, before food reserved in the stems are withdrawn to the rhizomes and roots. Such regeneration of detached straw that has overwintered had not been reported previous for any other grass species.
Illustrations. • Habitat. Rosemary Buck making notes beside shallow tundra pool, in which Arctophila is the dominant plant. N.W.T., Banks Island, 74°12'N, 119°37'W. 1 August, 1999. • Habitat: aquatic leaves. Left, plants growing in water with floating aquatic leaves in the water and aerial stems beginning to emerge. Note the long pieces of detached straw from the previous season's growth on the shoreline. N.W.T., Aulavik National Park. Aiken 99–230. CAN. • Growing straw. A piece of stranded straw that had overwintered on the tundra beginning to grow. Aiken 99–230. CAN. • Experimental plants: Ottawa. Previous season's straw brought back from Banks Island to Ottawa and placed on moss. The green leaves shown here all developed from the straw. Aiken and Buck 2002. • Growth experiment plant. Green sprouts emerged from brown straw that was brought south to Ottawa. Aiken and Buck 2002. Scale bar in cm. • Straw with rhizome. A piece of previous season's straw (background) from which has sprouted a new rhizome with whorls of roots at the nodes (foreground). Aiken and Buck 2002. • Close-up of stem. Close-up of the terminal end of a piece of Arctophila straw stranded at the edge of the pond on sedge meadow. Note the straw-coloured distichous leaves of the previous season's growth and the new reddish leaves of current season's growth. N.W.T., Banks Island, Aulavik National Park, 73°46.0'N, 119°56.7'W. 10 July, 1999. Aiken 99–230. • Plantlet. Plant that developed from sprouts from previous season's straw, indicating the ability of this species to reproduce vegetatively. Banks Island, Sachs Harbour. Aiken and Buck 2002. Scale bar in cm. • Plants in habitat. Rosemary Buck holding a plant developing from previous season's straw. Note relatively little aerial growth and well-developed rhizomes and underground growth. N.W.T., Banks Island, Aulavik National Park, 74°12'N, 119°37'W. • Longitudinal section of straw. Below, a piece of previous season's straw that has been cut longitudinally near a node. Above, the piece that was removed with new growth curving to the left. Note a partition at the node of the straw that is otherwise hollow. Aiken and Buck 2002. • Stand and habitat. Fertile stand in boreal river swamp. Norway, Finnmark, Kautokeino. August, 1988. Photograph by R. Elven. Voucher at TROM. • Close-up of plant. Arctic plant from shallow marsh. Note slightly developed panicle, not yet flowering in mid-August. Plant probably mainly reproducing vegetatively from rhizomes. Norway, Svalbard, Sassen. 15 August, 1986. Photograph by R. Elven. Voucher at 0. • Close-up of panicle. Panicle of boreal plant. Norway, Finnmark, Kautokeino saami church village. 26 July, 1980. Photograph by R. Elven. Voucher at TROM. • Herbarium specimen, tiny plants. Relatively tiny plants that resemble Dupontia when the rhizomes are not prominent. Plants flowering at a very short height are typical of areas where geese have been grazing. Nunavut, Victoria Island, Cambridge Bay. 1987. S. Edlund and G. Argus 12745. CAN. • Herbarium specimen, medium-sized plant with rhizomes. Medium-sized plants. Lower leaves are typically distinctly shorter than the upper leaves in this species. In the Mackenzie delta, plants attain 2 m in height. Nunavut, Southampton Island, Salmon Pond. 1970. G.R. Parker SP-70–169C. CAN. • Herbarium specimen, large plant. Note distichous leaves that are longer towards the top of the culm than at the base. Nunavut, Victoria Island, Cambridge Bay. 1962. Steve Stephens 1125. CAN. • Type specimen of a forma. Holotype specimen of forma aristatum. CAN. • 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..