Flora of the Canadian Arctic Archipelago
English: Marsh fireweed,
French: Épilobe palustre.
Onagraceae, Fireweed family.
Published in Sp. Pl. 348. 1753.
Type: Described from Greenland, Novaya Zemlya, Vaigach Island, and arctic Siberia.
Vegetative morphology. Plants (10–)15–25(–40) cm high; perennial herbs. Only fibrous roots present. Ground level or underground stems horizontal; rhizomatous; elongate (and filiform, often not present on herbarium specimens). Ground level or underground stems scales present (in terminal buds on the rhizomes). Caudex absent. Aerial stems erect; not filiform. Aerial stem trichomes appressed, or retrorse (so that they lie appressed). Leaves present; distributed along the stems; opposite (near the roots and in smaller plants), or alternate (near the inflorescence in taller plants); dying annually and non-persistent. Petioles present, or absent (leaves sub-sessile); 0.5–2 mm long; hairy, or glabrescent; puberulent (if applicable). Petiole hairs appressed; wavy (sparse). Leaf blades simple. Leaf blade bases attenuate. Leaves not grass-like. Blades 10–30(–40) mm long, (2–)3–5(–9) mm wide, spreading, linear or lanceolate, flat, appearing single-veined. Blade adaxial surface glabrous. Blade abaxial surface glabrous (mostly, sometimes with a few hairs on the midvein). Blade margins entire, glabrous; apices acuminate (usually), or acute.
Reproductive morphology. Flowering stems with leaves. Flowering stems hairy. Flowering stems pubescent. Flowering stem hairs simple; shorter than the diameter of the flowering stem; white or translucent. Inflorescences racemose (flowers in the axils of well-developed leaves); diffuse; elongating as the fruit matures. Pedicels with non-glandular hairs. Flowers per inflorescence (1–)2–6; small, or medium-sized, or large. Sepals conventional; 4; free (valvate in bud and appearing fused at that stage, gradually splitting to the base as the flower opens); 1.1–1.3 mm long; 3.5–5 mm wide; green. Calyx glabrous. Petals conventional; free; 4; white, or pink (fading bluish); lanceolate; slightly lobed or undulating (with a distinct notch, approximately 25% of the length of the petal); 4.5–6 mm long; 1–1.5 mm wide. Stamens 8; stamen filaments glabrous. Anthers 0.4–0.6 mm long. Nectaries present (rudimentary). Ovary inferior; carpels 4; syncarpous. Ovaries hairy; villous. Ovary hairs very dense; white. Styles 1; 2–4 mm long; straight. Stigmas per ovary 4. Placentation axile. Ovules per ovary numerous. Fruit stalked; stalk (15–)20–30 mm long; dry; a capsule; elongate-cylindrical; purple (when young), or brown (drab); (25–)30–50(–60) mm long; 1.2–1.5 mm wide; hairy; surface appearing veinless; not distinctly flattened; dehiscent; splitting to the base into separate segments; teeth 4. Seeds numerous; 1–1.2 mm long; black (with plumose tufts 7–8 mm long); surfaces smooth.
Chromosome information. 2n = 36.
2n = 36. Böcher (1938a, northern Europe); Löve and Löve (1948, Iceland; 1956, Iceland; 1966, northeastern USA; 1982a, central Canada); Lövkvist in Weimarck (1963, Sweden); Löve and Ritchie (1966, central Canada); Johnson and Packer (1968, northwestern Alaska); Zhukova and Petrovsky (1976, western Chukotka); Zhukova et al. (1977, northeastern Asia); Krogulevich (1976a, northern Siberia); Seavey and Raven (1977); Zhukova (1982, northeastern Asia); Krasnikov and Schaulo (1990, Siberia). Several more southern counts.
Ploidy levels recorded 4x.
Ecology and habitat. Substrates: wet meadows, along streams, lakeshores; imperfectly drained moist areas; rocks, gravel, sand, moss (muskeg); with high organic content (submerged organic over sandy loam (CAN 483132)); acidic. Rocky lake shore near sand dunes (CAN 200186); Carex aquatilis var. minor meadow (CAN 535486); closed depression in poorly drained organic soil (CAN 483133); Carex aquatilis - Comarum palustre marsh (CAN 483135); raised dry gravel mounds with Arctophila fulva and Cardamine pratensis (CAN 583987).
North American distribution. Alaska, Yukon, continental Northwest Territories, Nunavut Islands, continental Nunavut, northern Quebec, Labrador. Range in the Canadian Arctic Archipelago limited. Rare. Low Arctic. Arctic islands: Southampton (single record from the Archipelago (CAN 583987)).
Northern hemisphere distribution. Circumpolar, or circumboreal. Northern Iceland, Northern Fennoscandian, KaninPechora, Polar Ural Novaya Zemlya, YamalGydan, Taimyr Severnaya Zemlya, Kharaulakh, West Chukotka, South Chukotka, East Chukotka, West Alaska, North Alaska Yukon, Central Canada, Labrador Hudson Bay, West Greenland, East Greenland.
General notes. Bednara (1977, 1978) described the development of the monosporic, tetranucleate embryo sac of E. palustre, and the embryology of the macrospore tetrad.
A CAN specimen from Coral Harbour was examined by Elven (May 2005) and confirmed to be this species.
Illustrations. • Habitat. Small white dots behind the markers are flowers of this dwarf species that were conspicuous against the green of a sedge meadow. The larger white dots are Eriophorum. Nunavut, Southampton Island, Coral Harbour. Aiken and Brysting 01–088. CAN 583987. • Habitat. Small white dots between the markers are flowers of this dwarf species in a wet sedge meadow beside a Salix shrub. Nunavut, Rankin Inlet. Aiken and Brysting 01–056. CAN 583958. • Close-up of plants. Small flowers with four white petals in a wet sedge meadow beside a Salix shrub. Side view of buds show pinkish green sepals on top of a swollen inferior ovary. Nunavut, Rankin Inlet. Aiken and Brysting 01–056. CAN. • Close-up of plant. Dwarf species with a racemose inflorescence that has three flowers borne on pedicels that arise in the axils of leaves. Note the long, swollen, inferior ovary, the pinkish brown sepals and the white petals. Aiken and Brysting 01–088. CAN 583987. • Close-up of flower. Note four narrow sepals that are green on the inner surface, reddish on the outer surface, and alternate with the four white, notched petals. There are 4 dehisced anthers opposite the sepals and an inner whorl of 4 post-anthesis anthers opposite the petals and close to the swollen stigma. Nunavut, Coral Harbour, Southampton Island. 30 July, 2001. Aiken and Brysting 01–056. CAN 583987. • Side view of bud. Note the characteristically hairy inferior ovary, and the pinkish green lanceolate sepals. These are alternate with the petals. Only half a petal is seen in this view so that the notch is not visible. Nunavut, Rankin Inlet. 27 July, 2001. Aiken and Brysting 01–056. CAN 583958. • Herbarium specimen. Herbarium specimens showing elongate, filiform, leafy ground-level stems that are characteristic of this species. Aiken and Brysting 01–056. CAN 583958. • 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..