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Botanical descriptions Habitat and ecology Distribution
Diagnostic characters : | Bark slightly fissured, bark fibres penetrating into the wood. Flowers unisexual on the same plant, male in spike-like catkins, female, sessile, densely clustered on lateral spikes. Acorn sunked in cupule covering ½ of the acorn at maturity, nut smooth. |
Habit : | Evergreen tree up to 20 m tall, with 50 cm in diameter. Branches ascending to main trunk. |
Trunk & bark : | Trunk straight. Bark smooth, finely fissured, white or whitish grey, outer bark thin, inner bark red, fibrous. |
Branches and branchlets or twigs : | Twigs terete, densely lenticelled, glabrous in mature, puberulent yellowish when young. |
Exudates : | Exudate absent. |
Leaves : | Leaves simple alternate and spiral, 10-17 by 5.5-9 cm, coriaceous, oblong or elliptic-ovate to obovate, apex obtuse, base acute or attenuate, margin entire. Blade glabrous on both sides. Midrib flat above, primary vein single, secondary veins oblique to the midrib, widely parallel, tertiary veins undistinctly oblique. Petiole long, shortly hairy when young, blackening when mature. |
Inflorescences or flowers : | Flowers unisexual on the same plant, male flowers in spike-like catkins, female sessile on lateral spikes. |
Fruits : | Fruits acorn, united by 3 to 5 at 3/4 of the cupule, the later enveloping almost the whole acorn when young but only the half when mature, 3.2-3.4 by 3.0-3.2 cm sized. Acorn subovoid or obovoid, sometimes slightly trigonal, smooth. |
Seeds : | Seed 1. |