Hopea odorata Roxb.

Hopea species are evergreen trees. Bark gray or brown, smooth, at some length fissured or flaked, with white resin. Leaves simple, alternate, narrow oblong-lanceolate to oblanceolate-elliptic, base obtuse to oblique, margins entire, apex acute to acuminate, coriaceous, leathery, usually hairy with domatia in the axils of the lateral veins, midrib impressed above and prominent beneath, lateral veins pinnate, tertiary veins scalariform, petiole slender, stout, stipules linear, fugacious, caducous, scars inconspicuous. Inflorescence axillary or terminal, lax panicles or unilateral racemes. Flowers bisexual, pedicel short to sessile, bracts early caducous or ebracteate, calyx 5 lobed, tubular with very short, imbricate densely stellate tomentose lobes, adnate to receptacle, 2 outer longer, ovate, apex obtuse, thick, growing soon after anthesis, becoming much longer than others, 3 inner lobes short, suborbicular, thin near margins, apex usually mucronate, petals 5, imbricate, oblong, fleshy, pubescent in bud, glabrous inside, densely stellate outside. Stamens 10-15, base connate, adnate to petals, usually caducous along with the petals, filaments subulate, usually inner ones shorter and sterils, outer ones longer, anthers medifixed, short, connective thin near apex. Ovary tri-locular, ovoid, ovules in two rows, axile placentation, style filiform, short, cylindric, stigma thick. Fruit large, nutlike, globose-ovoid, enclosed in calyx tube with 2 accrescent lobes like wings. Seed 1, adnate at the base, cotyledons unequal.

Hopea species flowers are complete, bisexual, i.e., with functional male (androecium) and female (gynoecium), including stamens, carpels and ovary. Pollination is entomophilous i.e., by insects, or cleistogamy i.e., by self or allogamy i.e., by cross pollination. Flowering/Fruiting: February—April/May—June.

Seeds may be dispersed by autochory i.e., self dispersal, anemochory i.e., wind dispersal, zoochory i.e., dispersal by birds or animals, anthropochory i.e., dispersal by humans.

Evergreen trees, about 30-40 m tall, trunk girth about 4 m. Bark dark brown to grayish brown, smooth, reddish or yellow inside, furrowed longitudinally, with white resin, branches spreading, branchlets drooping, rugulose to smooth, puberulent, soon becoming glabrous, vegetative buds and inflorescences puberulent. Leaves simple, alternate, lanceolate-oblong to ovate-oblong, about 5-15 x 3.2-5 cm across, base acute, margins entire or undulate, apex obtusely acuminate, coriaceous, green glabrous above, paler beneath, usually hairy with domatia or gland-like swelling in the axils of the lateral veins, midrib impressed above and prominent, arched and porous beneath, lateral veins pinnate 9-12, tertiary veins parallel or perpendicular to the midrib, petiole slender, stout, about 1-2 cm long, stipules linear, scars inconspicuous. Inflorescence axillary, branched panicles up to 12 cm long, puberulent. Flowers bisexual, fragrant, pedicel short or subsessile, calyx 5 lobed, unequal, tubular with very short, imbricate, slightly puberulent, adnate to receptacle, 2 outer longer, ovate-deltoid, apex obtuse to subacuminate, thick, growing soon after anthesis, about 4 mm long, 3 inner lobes short, suborbicular, thin near margins, apex acute, petals 5, imbricate, falcate-oblong, fleshy, pubescent in bud, pale yellow, pubescent outside. Stamens 15, base connate, adnate to petals, usually caducous along with the petals, filaments subulate, base flattened and tapering above, anthers medifixed, short, connectives usually as long as anthers. Ovary tri-locular, ovoid, glabrous or punctate, ovules in two rows, axile placentation, stylopodium conical, style filiform, cylindric. Fruit large, nutlike, globose-ovoid, about 3-6 x 5-8 mm across, base saccate, apiculate, enclosed in calyx tube with 2 accrescent lobes like wings, oblong-broadly spathulate, about 3.8 cm long, longitudinal veins 7-11, joined by cross veins, smaller lobes ovate.

Hopea species are susceptible to various insect pests, virus and fungi, affecting leaves, fruits and roots.

Along streams of tropical evergreen forests.

Vulnerable (IUCN).

Wood used in making boats, building construction, bark and resin used in folk medicine and tannin obtained from bark, wood and leaves used in leather tanning.