Perennial herb. Stems slender, erect, sparsely hairy at nodes, brittle, 30-90 cm tall, arising from a branched woody stock with persistent lf bases. Lvs pinnate; lamina 5-15 × 5-12 cm; lateral leaflets in 3-(5) pairs, ovate to elliptic, obtuse, bicrenately lobed, each usually with a basal proximal ± deflexed pinnule or lobe; midrib and petiolules narrowly winged; wing expanded at bases of petiolules; terminal leaflet ternate; petiole 1/4-1/2 length of, or rarely =, lamina. Peduncles 2-10 cm long; umbels 2-6-flowered; pedicels 1-5 cm long. Sepals c. 8 × 5 mm, obovate. Petals yellow, obovate, up to 1 cm long. Capsule linear, somewhat constricted between seeds, 20-50 × 1.5-2 mm.