Key to Korean Bistorta
(modified from Park, Chong-wook et al. (2018) 82. Polygonaceae in Flora of Korea Vol. 3, Caryophyllidae Flora of Korea Editorial Committee and National Institute of Biological Resources.)
1. Rhizomes not contorted, usually moniliform, often branched; inflorescences terminal and axillary
1. Rhizomes contorted, not moniliform; inflorescences terminal
2. Inflorescences bearing bulbils in lower part; petiole not winged
2. Inflorescences without bulbils, petiole winged at least in upper part.
3. Basal leaves ovate to broadly ovate, base deeply cordate
3. Basal leaves linear, oblong, narrowly to broadly lanceolate, or narrowly triangllkar, base truncate, rounded or weakly cuneate, rarely shallowly cordate.
4. Abasxial surface of leaves moderately to densely pubescent with simple hairs
5. Plants usually 0.8-1 m tall
5. Plants 20-45 cm tall
6. Secondary inflorescences globose or broadly ellipsoid
6. Secondary inflorescences cylindrical
4. Abaxial surface of leaves glabrous
7. Basal leaves lanceolate oto broadly lanceolate or narrowly triangluar, 3.3-9.8(-11.5) cm wide
B. officinalis
7.1 Basal leaves broadly lanceolate to triangluar 5.6-9.8(-11.5) cm wide, blade length/maximum width ratio 1.8-3.2, base shallowly cordate, rarely truncate; petiole wings more or less narrow
subsp. offcinalis (承篮蕾裹部府)
7.1 Basal leaves lanceolate, 3.3-5.5 cm wide, blade length/maximum width ration 4-6.5(-8.5), base truncate to cuneate; petiole wings rather broad
7. Basal leaves linear or narrowly lanceolate or oblong-lanceolate, 0.6-3 cm wide