Shorea laevis Ridl., Fl. Mal. Pen. 1 (1922)

Synonyms
Hopea laevifolia Parijs
Shorea laevifolia Endert
Shorea rogersiana Raizada & Smithinand

Diagnostics
Emergent tree up to 75 m tall and 148 cm dbh. Stem with resin. Stipules up to ca. 8 mm long. Leaves alternate, simple, penni-veined, glabrous and shiny. Flowers ca. 5 mm in diameter, greenish-yellow, placed in panicles. Fruits ca. 10 mm long, green, with three ca. 30 mm long wings, wind dispersed.

Description
Vast, prominently buttressed tree. All vegetative parts epilose. Twig c. 1 mm diameter apically, much branched, slender, terete, smooth; stipule scars small, obscure. Bud c. 3.5 by 1.5 mm, narrowly ovoid. Stipule to 8 by 2 mm, narrowly lanceolate, acute, fugaceous. Leaves 6.5-10 by 2.5-4 cm. narrowly ovate-lanceolate; falcate, thinly coriaceous, cream lepidote beneath in mature trees; base subequal, broadly cuneate; acumen to 2 cm long, slender; nerves 11-14 pairs, slender, coriaceous, dense, curved, at c. 50-60 degrees. unraised on either surface as also the midrib; tertiary nerves slender, densely scalariform, diagonal to nerves; petiole 1-1.5 cm long, slender, geniculate. Panicle to 12 cm long, terminal or axillary, slender, terete, shortly persistently pale cream grey pubescent, +/- glabrescent; singly or doubly branched, branchlets to 3 cm long, bearing to 9 distichous flowers; bracteoles to 2 mm long, linear, pubescent, fugaceous. Flower bud to 2 mm long, globose. Calyx shortly pale cream-brown tomentose outside, glabrous within; 3 outer lobes ovate-deltoid, subacute; 2 inner lobes smaller, suborbicular. Petals small, oblong, shortly pubescent on parts exposed in bud. Stamens c. 50; filaments slender, tapering, sparsely barbate towards the apex; anther oblong, the longer, outer, sacs barbate at base and apex; appendage to connective small, barbate. Ovary and stylopodium small, conical, densely buff tomentose, crowned by a short glabrous style. Fruit calyx shortly buff pubescent on both surface; 3 longer lobes to 6.5 by 1 cm, oblong, chartaceous, slightly broader at the obtuse apex, untapering but saccate and adpressed to the nut at the base; 2 shorter lobes to 4 by 0.5 cm. subacute, otherwise similar. Nut to 1.5 by 0.9 cm, ovoid, shortly densely evenly buff pubescent; style remnant to 4 mm long, tapering, frequently bent over. [from Flora Malesiana]

Ecology
In undisturbed mixed dipterocarp forests up to ca. 600(-1000) m altitude. Mostly on hillsides and ridges on skeletal or dry soils, but also on alluvial sites. On clay to sandy soils.

Uses
The timber is used.

Distribution
Peninsular Burma and Thailand, Peninsular Malaysia, Sumatra, Borneo.

Local names
Borneo: Bangkirai, Bangkirai lampong, Bangkirai tanduk, Banuas, Banuas layang, Cengal, Damar kapala tupai, Gelam, Merenting, Mikai, Penjau, Selangan batu, Selangan batu bukit, Selangan batu kumus, Tengelan menpelan.
Malaysia: Kumas, Kumas merah, Kumas hitam, Selimbar, Damar laut kuning.