Lactuca triangulata var. sachalinensis Kitamura; Pterocypsela triangulata (Maximowicz) C. Shih.

Herbs to 1 m tall or more, biennial or perennial. Roots ramose. Stem solitary, usually purplish red, erect, branched in apical half or third, glabrous. Lower and middle stem leaves ± glabrous, margin with unequal and triangular teeth; basal portion winged petiole-like, 6-13 cm, base broadly auriculately to hastately clasping stem; apical portion triangular, broadly ovate, or broadly ovate-cordate, 8.5-13 × 9-16 cm. Upper stem leaves similar to middle stem leaves or basally shortly cuneate or winged petiole-like and auriculately or sagittately clasping and apically elliptic to rhombic. Uppermost leaves with semiamplexicaul base. Synflorescence rather narrowly paniculiform, with numerous capitula. Capitula with 10-16 florets. Involucre cylindric, 1-1.1 cm at anthesis, to 1.5 × 0.5-0.6 cm in fruit. Outer phyllaries narrowly triangular to lanceolate, longest ca. 7 × 1 mm, apex acute; inner phyllaries 8, usually purplish red, apex acute to obtuse. Florets yellow. Achene 4-6 mm; body blackish, reddish, or dark brown, ellipsoid, compressed, broadly winged, 2-2.5 mm wide, with 1(or 2) prominent rib on either side, apically contracted into an apically pale stout 0.1-0.5 mm beak. Pappus 6-8 mm, caducous. Fl. and fr. Jun-Sep. 2n = 18.

Grasslands on mountain slopes, mountain forests, forest margins, trailsides; 700-1900 m. Hebei, Heilongjiang, Jilin, Liaoning, Shanxi [Japan, Korea, SE Russia].