Flora of the Canadian Arctic Archipelago
| Flora of the Canadian Arctic Archipelago | |
English: Nuttall's alkali grass,
French: Puccinellie de Nuttall,
Inuktitut: Iviit, ivisuka, ivitsuskaka.
Poaceae, Grass family.
Published in In Jepson, Fl. Calif. 1: 162. 1912.
Type: Described from U.S.A.: North Dakota, Mandan, leg. Nuttall.
Synonymy. Poa nuttalliana Schult., Mant. 2: 303. 1824.
Puccinellia borealis Swallen, Journ. Wash. Acad. Sci. 34: 19. 1944.
Phippsia borealis ( Swallen ) Á. Löve and D. Löve, Bot. Notiser, 128: 498. 1976.
Puccinellia deschampsioides T.J.Sørensen, Meddel. Gronl. 126: 31. 1953.
Phippsia deschampsioides ( T.J.Sørensen) A. Löve and D. Löve, Bot. Not. 128: 499. [1975] 1976.
Vegetative morphology. Plants 18–40 cm high; perennial herbs; caespitose. Only fibrous roots present. Ground level or underground stems absent. Aerial stems erect. Leaves mainly basal; alternate; marcescent. Prophylls 10 mm long; with smooth veins; lacking pronounced keels. Petioles absent. Sheaths present; with the margins fused only in the lower part, or with the margins not fused; glabrous; sheath collars present. Ligules present; 1.5–3.5 mm long; glabrous, or hairy; ovate-oblong, or transversely oblong. Ligule apices obtuse, or truncate; erose. Leaf blades simple. Leaves grass-like. Blades 30–100 mm long, 0.4–0.7 mm wide (when rolled), appressed to the stem or spreading, rolled in bud, linear, flat or folded or involute, veins parallel, midvein similar in size to other veins in the leaf. Blade adaxial surface glabrous or scabrous. Blade abaxial surface glabrous.
Reproductive morphology. Flowering stems two or more per plant. Flowering stems circular or oval in cross section. Flowering stems culm nodes not exposed (on flowering culms), or becoming exposed (along stolons); number visible 0–1. Inflorescences paniculate; diffuse; lanceolate to ovate; 7–17 cm long; 15–75 mm wide. Inflorescences main axis glabrous to scabrous. Number of inflorescence branches at lowest node 2–5. Inflorescence primary branches 35–105 mm long; scabrous; with appressed secondary branches, or with spreading secondary branches. Spikelets oblong; 4–8 mm long; 1.4–2.5 mm wide. Florets per spikelet (3–)4–6(–8). Two glumes present. First glume 0.55–0.75 × the length of the second glume; 0.2–0.25 × spikelet length; 2–2.5 mm long; ovate; glabrous; margins scabrous (appearing minutely fringed under high magnification); veins 1 (faint); apex acuminate, or acute. Second glume 0.4 × as long as the spikelet or less; shorter than the lowest floret; 1.2–2.2 mm long. Second glume elliptic. Second glume with trichomes; margins scabrous; veins 3 (faint). Rachilla pronounced between the florets, or not pronounced between the florets; terminating in a vestigial floret; internode 0.5–0.7 mm long; internode 0.06–0.13 mm wide; internode glabrous. Callus differentiated; hairs 0–0.2 mm long; hairs shorter than the floret. Lemma oblong; 2.2–3 mm long; rounded on the back; surface shiny, or dull; surface glabrous, or hairy; surface with trichomes on veins only (long, sparse callus hairs); veins 5; apex rounded; apex entire, or erose; apex scabrous. Length of trichomes more than 25 um (evenly spaced). Lemma awnless. Palea well developed; 2–2.5 mm long; veins scabrous, or hairy. Flowers bilaterally symmetrical (zygomorphic). Perianth represented by lodicules. Stamens 3. Anthers 0.6–0.9 mm long. Ovary superior; carpels 3; syncarpous. Styles 2. Placentation basal. Ovules per ovary 1. Fruit sessile; dry; a caryopsis; 0.9–1.1 mm long; indehiscent. Seeds 1.
Chromosome information. 2n = 56.
2n (8x) = 56. Böcher and Larsen (1950, Greenland); Jørgensen et al. (1958, Greenland); Löve and Löve (1981a, northern Canada).
Ploidy levels recorded 8x.
Ecology and habitat. Substrates: river terraces, seashores; dry, moderately well-drained areas; gravel, sand, silt; halophytic, or circum-neutral.
North American distribution. This taxon (under the name P. borealis) was thought to be spreading east from Beringia into North America (Porsild and Cody 1980). It was abundantly weedy in disturbed areas of the gravel bar at the town site of Tuktoyaktuk in 1989, and may be expected to spread to similar sandy and gravelly sites, especially those disturbed by human activities. On the Canadian Arctic Islands, it has only been collected at Cambridge Bay, Victoria Island, where it is abundant and weedy (personal observations, Consaul and Gillespie, 1997). Alaska, Yukon, Northwest Territories Islands, continental Northwest Territories, Nunavut Islands, continental Nunavut. Range in the Canadian Arctic Archipelago limited. Uncommon (but abundant where present). Low Arctic. Arctic islands: Victoria.
Northern hemisphere distribution. Kharaulakh, Yana–Kolyma, West Chukotka, South Chukotka, West Alaska, North Alaska – Yukon, Central Canada, Labrador – Hudson Bay, West Greenland.
General notes. Puccinellia borealis has been synonymised under P. nuttalliana in the treatment for Flora of North America (Davis and Consaul 2007). Elven et al. (2003) included this name (P. borealis) as representing a distinct taxon in the Panarctic Flora Checklist. Davis and Soreng (2003) also treated P. borealis as a separate species, and commented "this might be better treated within P. nuttalliana."
Puccinellia nuttalliana (as P. borealis) was reported in the archipelago from Beechey Island by McJannet et al. (1993), but the voucher specimen at CAN was annotated to P. angustata by S.G. Aiken, April 1994. In 1997, Consaul and Gillespie (personal observations) reported this taxon under the name P. borealis as abundant and weedy on Victoria Island. It is a species that would be expected to spread to other locations in the southern islands of the Arctic Archipelago, helped by anthropogenic influences.
Puccinellia arctica and P. borealis were added to the flora of the Canadian Arctic Archipelago (Porsild 1957), in the supplement Porsild (1964),
The characters given as separating these species were as follows:
Plants littoral, panicle 6–9 cm long, anthers 1.5 mm long…. P. arctica,
Plants non-littoral, common to weedy on disturbed subarctic riverbanks and lakeshores; panicle 10–25 cm long, anthers 0.6–0.7 mm long …P. borealis.
Kartesz (1999) placed P. borealis into synonymy under P. arctica, but gave no reason for doing so. It is conceivable that he was influenced by Porsild's (1951) statement that P. borealis of the sea-coast probably should be referred to P. arctica, or, alternatively, by Welsh's (1974) description of the distribution of P. arctica as Alaska "eastward to the Labrador (P. borealis Swallen)" (Consaul and Gillespie 2001). No support for the synonymy in Kartesz (1999) was found by Consaul and Gillespie (2001). These authors found that, as well as the anther lengths being different, the structure of the lemma apex margin differs between the two taxa.
Lemma margin with trichomes greater than 25 micrometres long and evenly spaced…. P. borealis
Lemma margin with trichomes less than 25 micrometres long, unevenly spaced … P. arctica.
Specimens of P. borealis are close morphologically to western plants of P. vaginata with intermediate-sized lemmas and anthers. They may be investigated as potential hybrids.
Ovenden (1986) found P. nuttalliana (P. borealis) and Arctagrostis latifolia were common on the lake bed of Illisarvik, the site of a thermokarst lake that was artificially drained in August 1978. By 1985, the lake bed was dry in most areas and wind erosion was extensive.
Illustrations. • Plant habitat. Plants growing on dry mud of drained lake bed. N.W.T., Illisarvik, Richards Island, Mackenzie Delta, 69�28.8'N, 134�35.14'W. 12 August, 1997. L.J. Gillespie 6433 and L.L. Consaul. CAN. • Pressed specimen. Plant approximately 30 cm tall. Nunavut, Cambridge Bay. Gillespie and Consaul 6327. CAN 584072. • Type specimen. Isotype of Puccinellia deschampsioides Greenland, Arfersiorfik Fiord, 68�20'N, 51�5'W. 20 July, 1924. M.P. Porsild. CAN 315848. • Herbarium specimen. Herbarium specimen of Puccinellia borealis. Nunavut, Victoria Island, Cambridge Bay. 19 July, 1962. Stephens 1074. CAN. • Close-up of spikelet. Characteristic small florets about 2 mm long, frequently clustered at the ends of long branches. Arrow points to a cluster of three spikelets crowded at the end of an inflorescence branch. Nunavut, Cambridge Bay. Gillespie 6327 and Consaul. CAN. 584072. • Close-up of lemma apex. Apex of lemma as seen under 100x, showing large, spinulose trichomes greater than 25 micrometers long forming a regularly scabrous margin. Alaska, along Yukon River. E. Lepage 23329. 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.
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