荞麦 qiao mai

Fagopyrum emarginatum (Roth) Meisner; ?F. emarginatum var. kunawarense Meisner; F. zuogongense Q. F. Chen; Polygonum emarginatum Roth; P. fagopyrum Linnaeus.

Herbs annual. Stems green or red when mature, erect, 30-90 cm tall, branched above, glabrous or papillate on one side. Petiole 1.5-5 cm; leaf blade triangular, 2.5-7 × 2-5 cm, both surfaces papillate along veins, base cordate or nearly truncate, apex acuminate; ocrea caducous, ca. 5 mm, membranous, oblique, not ciliate. Inflorescence axillary or terminal, racemose or corymbose; peduncles 2-4 cm, papillate along one side; bracts green, ovate, 2.5-3 mm, margin membranous, each 3- or 5-flowered. Pedicels longer than bracts, not articulate. Perianth pink or white; tepals elliptic, 3-4 mm. Anthers pinkish. Styles heterostylous. Achenes exceeding persistent perianth, dark brown, opaque, ovoid, sharply trigonous, 5-6 mm, surfaces flat. Fl. May-Sep, fr. Jun-Oct. 2n = 16*, 32*.

Probably native to China, but commonly cultivated and easily escaping [cultivated in Bhutan, Korea, Mongolia, Myanmar, Nepal, Russia, and Sikkim; also Australia, Europe, and North America].