Polygonaceae A.L. de Jussieu
Buckwheat family.
Polygonaceae, buckwheat family.
Vegetative morphology. Plants dwarf shrubs, or mid shrubs; 1–80 cm high. Caudex present, or absent. Aerial stems erect, or ascending, or prostrate; circular or oval in cross-section; glabrous. Leaves distributed along the stems, or in a basal tuft; alternate; marcescent. Stipules present; scale-like; 0.5–15 mm long; 0.5–8 mm wide; sheathing; brown, or white, or colorless. Stipules glabrous. Stipules apex acute, or truncate. Petioles 0.5–50 mm long; glandular dots at the base of the leaf absent; glabrous, or hairy; pubescent (when present); hairs less than the diameter of the petiole. Petioles hairs spreading, or erect; curved, or wavy. Sheaths persisting, or breaking down into fibres; forming a conspicuous build up at the base of the plant, or not forming a conspicuous build up at the base of the plant; greyish brown, or brown, or straw pale yellow; with the margins fused to the apex, or with the margins fused only in the lower part; glabrous. Leaf blade bases cordate, or truncate, or obtuse, or acute, or cuneate, or attenuate. Blades 1.2–50 mm long; 0.5–20 mm wide. Blades appressed to the stem, or spreading, or divaricate; herbaceous, or leathery, or succulent; oblong, or elliptic, or lanceolate, or ovate, or oblanceolate, or reniform. Blades adaxial surface glabrous. Blades abaxial surface glabrous, or hairy. Leaf apices acute, or obtuse, or rounded.
Reproductive morphology. Flowering stems present. Flowering stems with leaves, or without leaves; glabrous. Leaf or reduced bract closely associated with the base of the inflorescence present, or absent. Inflorescence racemose, or paniculate, or cymose (Koenigia); dense, or diffuse; linear, or lanceolate, or ovate, or ellipsoid, or cylindrical; 0.5–15 cm long; 0.5–10 mm wide; main axis glabrous. Pedicels present, or absent. Pedicels bract leaves 0.3–3.5 mm long; 0.2–2 mm wide. Flowers per inflorescence 3–300; small, less than 5 mm in diameter or length. Calyx sepals 3–5; free, or fused; 1–5 mm long; 0.5–2 mm wide. Calyx purple, or red, or black, or pink, or white or translucent; glabrous. Petals absent. Stamens present and probably functional. Stamens 3–6; filaments glabrous. Anthers 0.5–1.2 mm long. Gynoecia superior. Carpels syncarpous; 3. Styles 0.03–1.8 mm long. Styles basal portion smooth. Placentation basal. Ovules 1. Fruit dry; an achene; ovoid, or obovate; distinctly flattened, or not distinctly flattened; indehiscent. Fruit 1–4 mm long; 0.5–2.5 mm wide; black, or brown.
Chromosome information. Supposed basic chromosome number of family 7/10/11/12.
Distribution. Northern hemisphere distribution: circumpolar; Greenland, Canada, United States, Eurasia.
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).