Melicope knudsenii, a member of the Rutaceae (rue) family, is a tree 3 to 10 m (10 to 33 ft) tall with smooth gray bank and yellowish brown to olive-brown hairs on the tips of the branches. Leaves are variable, ranging from oblong to elliptic, 9 to 25 cm (3.5 to 9.8 in) long and 4.5 to 10 cm (1.8 to 3.9 in) wide. The lower surface of the leaves is uniformly covered with olive-brown hairs, but the upper surface is only sparsely hairy along the midrib. The densely hairy flowers are bisexual or may be unisexual. There are usually 20 to 200 flowers per cluster in the leaf axils. The sepals and petals are covered with silky gray hairs and the sepals persist in fruit. The fruits are 18 to 30 mm (0.7 to 1.2 in) wide and are comprised of distinct follicles 8 to 14 mm (0.3 to 0.6 in) long. The hairless exocarp is dotted with minute glands. The endocarp also lacks hairs. Seeds number one or two per carpel (ovule-bearing structure) and are about 5 to 6 mm (0.2 in) long.