 The bark is smooth and pale grey on young trees, becoming square-cracked and knobbly on old trees.The buds are pale brown, which readily distinguishes it from the related "Fraxinus excelsior" (black buds) even in winter.The leaves are in opposite pairs or whorls of three, pinnate, 15–25 cm long, with 3–13 leaflets; the leaflets being distinctively slender, 3–8 cm long and 1–1.5 cm broad.