Dipterocarpus grandiflorus Blanco

Very large hardly buttressed tree. Leaf bud, outside of stipule, parts of petals exposed in bud, ovary apex and sometimes twig densely evenly pale buff pubescent, parts otherwise glabrous. Twigs to 12 mm ø, stout, becoming grey-brown; internodes short, the leaves clustered around the twig endings. Buds to 2 by 1 cm, ovoid, acute; stipule to 18 by 5 cm, oblong-lanceolate, subacute. Leaves 10-18 by 5-12 cm, ovate, coriaceous, ± applanate; base obtuse or subcordate; acumen to 1 cm long, short, nerves 15-17 pairs, prominent beneath, spreading; tertiary nerves remotely scalariform, barely elevated; petioles 3-9 cm long, very long, slender. Inflorescences to 18 cm long, very long, slender, axillary, borne in dense groups behind the leaves, unbranched, bearing to 3 remote distichous flowers. Flower buds to 35 by 13 mm, fusiform. Stamens 30, exceeding style at anthesis; filaments broad, compressed, tapering, c. 1/3 the length of the relatively short broadly linear-lanceolate tapering anthers; appendages acicular, c. 2/3 length of anthers. Ovary tapering into the short stoutly columnar style; ovary and style puberulent in the basal half. Fruit pedicel to 2 by 4 mm, stout. Calyx tube to 7 by 3.5 cm, ellipsoid, with 5 pruinose, to 1.5 cm wide, prominent coriaceous wings continuous from base to apex; 2 longer lobes to 22 by 3 cm, oblanceolate-spa-tulate, obtuse, tapering abruptly to c. 1.3 cm wide at base; 3 shorter lobes to 2 by 1.5 cm, elliptic, subrevolute.

Often common, becoming semi-gregarious, in more seasonal climates in Semi-evergreen Dipterocarp forests; on small islands and on coastal hills in less seasonal areas, and in Malaya occurring frequently with Shorea curtisii on inland ridges to 700 m.

Can be grown by seedlings.