Plants 45–100 cm. Stem terete, striped, subglabrous. Basal leaves long-petiolate, petioles 5–8 cm; blade broad-triangular, ca. 14 cm, ternate-2–3-pinnate; ultimate segments lanceolate, 1.5–4 × 0.8–1.5 cm, base subtruncate to cuneate, irregularly serrate, apex long-acuminate or caudate. Upper leaves smaller, pinnate, petioles wholly sheathing. Umbels 3.5–4 cm across; peduncles 6–20 cm; rays 8–18, 2.5–4.5 cm, roughened; umbellules ca. 1 cm across, many-flowered; pedicels ca. 4 mm, unequal. Petals white, obovate. Styles ca. 1 mm. Fruit oblong-ovoid or long-ovoid, 3–3.5 × 1.5–2 mm. Fl. and fr. Jun–Aug.