Erect biennial or perennial. Stems up to 2 m high and 4 cm diam., woody and leafless in lower parts with distinct lf scars, with pith in centre and hollow in parts. Stem lvs with fine hairs on rachis and midribs, otherwise glabrous, 2-3-pinnate (seedling lvs 1-pinnate); ultimate segments ovate to lanceolate, pinnatisect or not lobed, serrate, 15-20 mm long, shortly petiolulate or sessile; lvs of infl.-branches much reduced; petiole sparsely to moderately hairy, striate. Umbels up to 20 cm diam.; rays numerous; bracts 10-12, narrowly ovate-lanceolate, sometimes serrate, up to 5 cm long; bracteoles 7-12, lanceolate. Fls numerous, white to purplish. Fr. dark brown, sparsely hairy, 12-18 mm long.