Carex bigelowii Torr. ex Schwein subsp. bigelowii
In Ann. Lyc. N. Y. 1: 67. 1824.
Nomenclatural section used by Flora of North America project subgenus Carex, sect. Phacocystis Dumortier
Carex bigelowii subsp. hyperborea (Drej.) Bocher
Carex consimilis Holm
Carex rigida Good.
Carex anguillata Drej.
Carex bigelowii forma anguillata (Drej.) Fern.
Carex bigelowii subsp. hyperborea (Drej.) Böcher
Carex consimilis Holm
Carex rigida Good 1794, not Schrank, 1789.
Carex concolor of authors not R.Br.
Carex vulgaris of authors
Carex hyperborea Drej.
Carex ensifolia Turcz.
Carex rigidioides Gorodk.
Plants less than 15 cm high, or more than 15 cm high (usually, coarse); 3–20(–30) cm high. Roots pallid-brown. Ground level or underground stems horizontal; rhizomatous, or stoloniferous; elongate. Scales present. Aerial stems erect; triangular in cross section; glabrous. Leaves mostly basal. Sheaths greyish brown, or brown. Ligules present. Blades straight; linear; flat, or revolute; not septate nodulose (distinguishes this species from C. aquatilis); glabrous (strongly ribbed). Blades adaxial surface glabrous.
Flowering stems conspicuously taller than the leaves. Leaf or reduced bract closely associated with the base of the inflorescence present; conspicuous and leaf-like; similar in length to the inflorescence, or shorter than the apex of the inflorescence; 2.5–3.5 cm long; sheathless (the base of the blade may enclose the stem at the node, but there is no sheath covering any part of the internode). Inflorescence spicate; (1.5–)3–6(–8) cm long; (5–)10–15 mm wide. Pedicels smooth. Inflorescence multispicate; 2–3(–4) spikes; lateral spikes borne on pedicels (usually pistillate, but occasionally with a few staminate flowers). Individual spike(s) ascending. Terminal spike wholly staminate (usually). Cladoprophyll present at the base of the peduncle of lateral spikes. Staminate flowers conspicuous. Floral scales shorter than the perigynium in fruit (green sides of the perigynia visible around the edges of the darker scales); black; with margins darker in colour than the midvein (midvien light brown or green); obtuse; 2.5–3.5 mm long; 1.2–2 mm wide; glabrous. Perianth absent. Anthers 3.3–3.7 mm long. Styles slender, not extending beyond the beak. Stigmas per style 2. Fruit surrounded by a perigynium. Perigynia fused to the apex except for a small aperture through which the style protrudes; broadly ovate; 2.3–3 mm long; 1.3–1.7 mm wide; contracted at the base into a stipe-like structure (0.15–0.45 mm long); erect or ascending; green (often with purple spots at the apex); surface dull; glabrous; papillose; appearing nerveless; with 2 keels; apices merely conical or rounded. Achenes filling the perigynia; lenticular.
Chromosome information. 2n = 68 and 70 (Faulkner, 1972).
Distribution. Circumpolar (some authors), or amphi-Atlantic (Porsild, 1957). Arctic. Range in the Canadian Arctic Archipelago wide-spread. Common. Arctic Islands: Baffin, Devon, Ellesmere, Southampton, and Banks (literature record).
Ecology and habitat. Substrate hummocks (mossy), along streams, tundra (often windswept), slopes, ridges (also raised sandy beaches), cliffs; dry, or imperfectly drained (less commonly); rock, gravel, sand; with low organic content. Typically found in high, dry ledges and ridges; also in sandy areas between boulders. Common associates in this habitat are Empetrum and Arctostaphylos. Carex bigelowii also occurs in meadows with other Carex and with Eriophorum. Somewhat less commonly found in moist tundra and along streams.
Notes. Polunin (1940) considered this a widespread and very variable species indicating that it may be strongly stoloniferous and 10–40 cm high or closely tufted and only 4–5 cm high. There is a form with narrow perigynia and long and stiff peduncles to the lower spikes which is sometimes separated as C. anguillata. Polunin (1940) concluded it was best to include this and all other forms in the eastern Arctic under the same name and this has generally been done. McLaren (1964) indicated that C. anguillata was an addition to the flora of the Arctic Archipelago. Two specimens that he collected on Baffin Island at Ogac Lake are at CAN. They are relatively delicate plants but within the concept of C. bigelowii. CAN 204794, collected from the head of Clyde Inlet, Baffin Island, was annotated by Porsild (1958) as ?C. anguillata (Drej.) Fern; "a peculiar form in which the terminal spikes are female at most with 1–2 male flowers near the summit".
Holub (1964) noted that the C. bigelowii complex is distributed over the whole Arctic but the plants from Central Europe, the British Isles and Fennoscandianvia differ from plants described from the type locality in the White Mountains of eastern USA He described the European taxon as C. bigelowii Torr. ex Schweinitz subsp. nardeticola Holub.
In moist areas, the plants become taller and occasionally have longer and more lax-flowered pistillate spikes (Porsild and Cody, 1980).
Chater (1980) noted that this is an extremely variable species whose infraspecific taxonomy is confused by its apparent similarity to small variants of Carex aquatilis in the arctic, by the occurrence of numerous hybrids, and by the fact that published work on it has never taken full account of the variation over the full range.
Carex bigelowii is self compatible, but protandry limits pollination within flowering shoots (Jonsson et al., 1996). A study of genetic diversity using allozyme electrophoresis revealed extensive genetic diversity, and indicates high levels of outbreeding in the past. Today, the species produces many seeds and has a large, long lived seed bank; yet very little seedling recruitment has been observed. In Iceland seedling recruitment has been observed only in disturbed sites. Reproduction is mainly by clonal growth (also observed in Swedish Lapland by Wikberg et al., 1994). The long internodes of the rhizomes break down over time resulting in a large number of independent fragments with the same genetic composition (Jonsson et al., 1996)
Demographic aspects in populations of the species were studied in Swedish Lapland by Wikberg et al. (1994) at three altitudes. Tiller densities from the highest altitudes increased significantly during the study period (10–20 years) while those from intermediate and lower altitudes stayed constant.
Experimental control of flowering was investigated by Heide (1992).
In a study of scale-dependent correlation's of Arctic vegetation and snow cover in southeastern Victoria Island, Schaefer and Messier (1995) found that C. bigelowii exhibited positive associations with various measures of snow cover. It is thought that snow cover may reduce the rate of desiccation, protect plants from abrasion, and insulate from low temperatures.
The impact of anticipated climate changes on the population growth and vegetative spread of Carex bigelowii was investigated by Carlsson and Callaghan (1994). They show that increases in nutrients, carbon dioxide and temperature (expected consequences of climate change in the Arctic) will lead to increased growth of the species, and that young "guerilla" type tillers will contribute significantly to vegetative spread.
Illustrations. • Close-up of plants. Loosely tufted plant. Leaf associated with the inflorescence equal to or shorter than it. Scale bar in cm. Nunavut, Baffin Island, Iqaluit. Susan Aiken 97–002, CAN. • Close-up of inflorescence. Inflorescence with a terminal male spike and two female spikes. Green sides of the perigynia visible around the darker scales. Nunavut, Baffin Island, Iqaluit. Susan Aiken 97–025, CAN. • Close-up of inflorescence. Male terminal spike, post-anthesis. Lower female spike has scales shorter than the perigynia. Nunavut, Baffin Island, Iquluit. Susan Aiken, 97–025, CAN. • Arctic Island distribution.
Cite this publication as: Aiken, S.G., Boles, R.L., and Dallwitz, M.J. 1999 onwards. ‘Cyperaceae of the Canadian Arctic Archipelago: Descriptions, Illustrations, Identification, and Information Retrieval.’ Version: 6th November 2000. http://http://www.mun.ca/biology/delta/arcticf/. Dallwitz (1980) and Dallwitz, Paine and Zurcher (1993, 1995, 2000) should also be cited (see References).
