Trichophorum cespitosum (L.) Hartm.
Cyperaceae, sedge family.
Handb. Skand. Fl., ed. 5, 259. 1849
Scirpus cespitosus L., Sp. Pl. 48. 1753.
Baeothryon
cespitosum (L.) A.Dietr., Sp. Pl. 2: 89. 1832.
Kreczetoviczia
cespitosa (L.) Tzvelev, Bot. Zhurn. 84, 7: 12. 1999
Baeothryon caespitosum (L.) Dietr.,
Scirpus caespitosus L.
Trichophorum austriacum Pall.
Scirpus caespitosus L.
subsp. austriacus (Pallas) Asch. & Graebn.
Scirpus
caespitosus var. callosus Bigel.
Vegetative morphology. Plants perennial herbs; 7–15 cm high; caespitose (densely); with wiry, smooth, erect ascending culms. Roots pallid-brown. Ground-level or under-ground stems not developed horizontally or vertically. Scales present. Aerial stems erect; filiform (wiry, 0.4–0.6 mm in diameter); circular or oval in cross-section; glabrous. Leaves in a basal tuft; alternate; existing for a single season or less, or marcescent. Petioles absent. Sheaths persisting; forming a conspicuous build up at the base of the plant (composed of sheaths and flat scales 2–3 mm wide); greyish brown; collars absent. Ligules present. Blades 5–30 mm long; 0.2–1 mm wide. Blades straight; linear; flat (or slightly folded, bract-like, callous tipped, and easily overlooked); veins parallel. Blades adaxial surface glabrous. Blades abaxial surface glabrous. Blade margins glabrous.
Reproductive morphology. Flowering stems present. Flowering stems conspicuously taller than the leaves; with leaves; hairy. Leaf or reduced bract closely associated with the base of the inflorescence present; reduced, or scale-like; similar in length to the inflorescence; 3–6 mm long; with sheath shorter than the blade; persistent. Inflorescence spicate; 0.3–0.6 cm long; 1.5–3 mm wide; a single spike. Individual spike(s) erect. Terminal spike with both sexes in each floret. Floral scales orange brown (often with empty scales between the reduced leaf and the florets); with margins paler than body of scale; ovate; 2–4 mm long; 1.8–2.2 mm wide; glabrous. Perianth represented by bristles; bristles inconspicuous. Stamens 3. Anthers 2–2.5 mm long. Carpels syncarpous. Stipes 3 mm long. Styles 1; base not enlarged, continuous with the achene (which distinguishes this species from Eleocharis). Placentation basal. Fruit not surrounded by a perigynium. Fruit surrounded by a perianth persisting as bristles (that are inconspicuous); an achene.
Chromosome information. 2n = 104. 104. - Löve and Löve (1956b Iceland, 1981c central Canada); Jørgensen et al. (1958 Greenland, 2n = c.104); Pojar (1973 western Canada, 2n = c.104); Zhukova and Petrovsky (1975 western Chukotka); Krogulevich (1976 northern Siberia, 2n = c.100); Zhukova (1980 S Chuk, 1982 north eastern Asia); Yurtsev and Zhulova (1982 northern Siberia). Several more southern counts.
Distribution. Northern hemisphere distribution: circumpolar; Greenland, Canada. Continental Northwest Territories, Nunavut Islands, Continental Nunavut, Northern Québec. Low arctic. Range in the Canadian Arctic Archipelago limited. Rare. Arctic Islands: Baffin (Beekman Peninsula (new since Porsild, 1957), Cormack Bay and Kimmirut).
Ecology and habitat. Substrates: hummocks (peaty), along streams, tundra (in damp hollows), slopes (in springy or grassy places); imperfectly drained moist areas, or on seepage slopes; calcareous; with high organic content, or peat. Habitats: in mucky, peaty sites; often on seepage slopes.
Notes. Polunin (1940) noted that all material in the eastern Canadian Eastern Arctic has the orifice of the upper sheath "short" and with a firm border, and the spikelets short and few-flowered, and thus belongs not to the European lowland head form (subsp. germanicum) but to the wide ranging "arctic-alpine" which is subsp. cespitosum.
Illustrations. • Plants in habitat. Tufted plant between the markers and at the edge of the water. Each stem topped with small unispicate inflorescence. Manitoba, Churchill. Aiken and Brysting 01–004. CAN. • Plants in habitat. Tufted "cespitose" plant with wiry stems topped with small unispicate inflorescences, and a fringe of dead leaves at the base. Hudson Bay lowlands, Manitoba, Churchill. Aiken and Brysting 01–004. CAN. • Close-up of plant. Plants approximately 15 cm high growing in a marshy area. Nunavut, Baffin Island, Soper River Valley. Aiken and Isles, 02–048. CAN. • Close-up of plant. Tufted plants with wiry stems, each topped with small unispicate inflorescences. Aiken and Brysting 01–004. CAN. • Close-up of plant in flower. Plants in flower with three white stigmas per flower exposed. Nunavut, Baffin Island, Soper River Valley. Aiken and Isles, 02–048. CAN. • Close-up of spikes. Flowering spikes with three white receptiive stigmas and three brown previously receptive stimas. Aiken and Isles, 02–048. CAN. • Close-up of spikes. Three wiry stems, each with a flowering spike with exposed anthers. • Close-up of inflorescence. Solitary spike at anthesis. Each flower is subtended by a scale-like browish-yellow bract. AIken and Brysting. 10–004. CAN. • Arctic Island distribution.
Cite this publication as: ‘S.G. Aiken, M.J. Dallwitz, L.L. Consaul, C.L. McJannet, L.J. Gillespie, R.L. Boles, G.W. Argus, J.M. Gillett, P.J. Scott, R. Elven, M.C. LeBlanc, A.K. Brysting and H. Solstad. 1999 onwards. Flora of the Canadian Arctic Archipelago: Descriptions, Illustrations, Identification, and Information Retrieval. Version: 29th April 2003. http://www.mun.ca/biology/delta/arcticf/’. Dallwitz (1980) and Dallwitz, Paine and Zurcher (1993, 1995, 2000) should also be cited (see References).
