Large deciduous tree up to 30 m. tall; bole up to 2 m. in diam., not buttressed; bark grey or grey-brown, exfoliating in large irregular scales up to 12·5 cm. in diam., leaving buff patches and producing a mottled appearance. Leaves paripinnate; petiole and rhachis up to 25 cm. long, puberulous; leaflets up to 11 × 3·5 cm., usually opposite, sometimes alternate, (5) 6–7 (8)-jugate, ovate to lanceolate, tapering gradually from near the base to a narrowly acuminate apex with a filiform tip, base of distal leaflets very asymmetric, of the proximal less so, upper surface dull, lower surface glabrous except for the pubescent midrib and a few hairs on the secondary nerves; petiolules 1–2·5 cm. long. Flowers pale green, in contracted panicles up to 20 × 2 cm., borne in leaf-axils and towards the base of the current year’s growth; peduncles up to 14 cm. long; pedicels 2–4 mm. long, densely puberulous. Calyx 1·1–2 mm. long, tomentellous, lobed almost to the base. Petals 5–6 mm. long, densely puberulous outside. Staminal tube 3–4 mm. long, densely puberulous inside, glabrous outside. Capsule 15–21 × 5–5·5 cm., clavate, apex rounded; valves pale brown, closely lenticellate, apex thickened and recurved, dehiscing from the apex and ultimately breaking away from the base of the capsule; points of attachment of seeds to columella small and inconspicuous. Seeds (including wing) 9–10 × 2·5 cm.