Eriophorum angustifolium subsp. triste (T. Fries) Hultén
Eriophorum triste (Th. Fr.) Hadac & Löve
Eriophorum angustifolium var. triste T. Fries
Plants with single unbranched stems, or with stems in loose clusters; less than 15 cm high, or more than 15 cm high; 8–20(–30) cm high. Roots pallid-brown. Ground level or underground stems horizontal; rhizomatous (rhizomes often missing from herbarium specimens); elongate. Scales present (on rhizomes). Aerial stems erect; not filiform; circular or oval in cross section, or triangular in cross section (at the apex); glabrous. Leaves distributed along the stems (in the lower half). Sheaths greyish brown, or brown; with the margins fused to the apex; glabrous. Ligules present; 0.5–1 mm long; transversely oblong; apices obtuse; entire. Blades straight; linear; flat, or caniculate; glabrous, or scabrous (minutely scaberulous along the margins).
Flowering stems conspicuously taller than the leaves; uppermost leaf arising above the middle of the stem (sheath funnel-shaped); glabrous. Leaf or reduced bract closely associated with the base of the inflorescence present; conspicuous and leaf-like, or reduced, or scale-like; shorter than the apex of the inflorescence; 1–3(–5) cm long; with sheath shorter than the blade. Inflorescence spicate; dense; 3–5 cm long; 20–40 mm wide. Pedicels scabrous (up to 2 cm long). Inflorescence multispicate; 2–4(–5) spikes (bell-shaped or narrowly bell-shaped at maturity); lateral spikes borne on pedicels (subtended by 1–3 bracts). Individual spike(s) erect, or pendent (at maturity). Bisexual spike(s) with empty bracts at the base. Terminal spike with both sexes in each floret. Floral scales black, or pale grey (translucent); with margins paler than body of scale; acute; 5–7 mm long; 2–3 mm wide; glabrous. Perianth represented by bristles; bristles dull white or yellowish (40–50 mm long). Anthers (1.7–)2.5–2.8(–3.5) mm long. Stigmas per style 3. Fruit not surrounded by a perigynium; an achene (widely obovoid); 2–2.5 mm long; black, or brown. Achenes trigonous.
Chromosome information. 2n = 60.
Distribution. Amphi-Atlantic. High arctic. Range in the Canadian Arctic Archipelago wide-spread. Common. Arctic Islands: Baffin, Devon, Ellesmere, Axel Heiberg, Parry Islands, Cornwallis, Banks, Victoria, Somerset, King William, and Southampton.
Ecology and habitat. Substrate wet meadows, marshes, along streams, slopes (wet, sometimes mossy); aquatic (occasionally found in stream beds), or imperfectly drained, or on seepage slopes, or dry (rarely); calcareous; rock (occasionally), sand, clay, moss; with high organic content, or peat. Most often reported along streams. It can be found in wet meadows with Carex misandra and Arctogrostis; it is also reported in moist ridged fens with Dryas and Cassiope.
Notes. A study of the effects of variable soil oxygen and nutrient availability of E. angustifolium and E. vaginatum was done by Gebauer et al. (1995) near Toolik Lake, Alaska. It was shown that growth in E. angustifolium was improved by soil anoxia, and that biomass allocation among plant parts was not significantly affected, indicating that the species is well adapted to flooded, wet habitat.
In a study of scale-dependent correlation's of Arctic vegetation and snow cover in southeastern Victoria Island, Schaefer and Messier (1995) found that E. angustifolium 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 during the winter season.
Polunin (1940) recognized this taxon and commented that he had long thought of it as a mere high-arctic phase, but was assured by Dr. Thorv. Sorensen that it is a well marked variety in East Greenland. He further commented that "neither of the named varieties recognizable in our area is considered fully separable or worth citing individually under "occurrence". While we have mapped specimens as either subsp. angustifolia of subsp. triste we are aware of intermediate specimens with merely a few sparse trichomes on the petioles. These we initially mapped as subsp. angustifolium but later, and without much conviction, revised to subsp. triste.
Jermy (1980) noted that in Eriophorum angustifolium, several arctic and alpine variants have been described, of which the most distinctive is this taxon that differs from subspecies angustifolium by having narrower leaves, capitate inflorescences and blackish scales. These characters were not found to reliably distinguish between the two taxa in the Canadian Arctic Islands.
Illustrations. • Plants in habitat. Plants growing in a river flood plain on calcareous silt and gravel. Nunavut, Ellesmere Island, Scoresby Bay 79°53'N, 71°33'W. S.G. Aiken 98–006. Photograph by Mollie MacCormac. • Plants in habitat. Isolated plants growing in the moist shelter of a boulder in glacial moraine. Nunavut, Ellesmere Island, near John Richardson Bay 80°21'N, 71°20'W. S.G. Aiken 98–050. Photograph by Mollie MacCormac. • Close-up of leaf sheath. Close-up of side view of leaf sheath showing funnel shape of the junction between the blade and the sheath. Collected Southampton Island, Bear's Cove Point, D.K. Brown, 815, 20 July, 1951. CAN 258630. • Close-up of leaf sheath. Close-up of front view of leaf sheath showing funnel shape of the junction between the blade and the sheath. Collected Nunavut, Devon Island, Truelove Inlet, Katherine Mackenzie, 26, 16 July, 1974, CAN 397516. • Close-up of inflorescence. Inflorescence at anthesis. Anthers shed pollen before the perianth bristles ("cotton") develop. CAN 220113. • Close-up of inflorescence. Inflorescence post-anthesis with perianth developing. CAN 566171. • Close-up of inflorescence. Mature spikes with fine brown spent anthers and white silky perianth bristles. • 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).
