Botanical Name: Dipterocarpus kerrii
Species: D. kerrii
*Dipterocarpus cuneatus Foxw.
*Dipterocarpus obconicus Foxw.
*Dipterocarpus perturbinatus Foxw.
Common Names:Kerr’s Keruing
Habitat:Dipterocarpus kerrii is native to Southeast Asia – Myanmar, Thailand, Malaysia, Indonesia, Philippines. Frequently gregarious in semi-evergreen and evergreen coastal dipterocarp forests in periodically or seasonally dry climates, on red lateritic soils, on undulating land and hills at elevations below 400 metres.
Dipterocarpus kerrii is a medium-sized to fairly large tree of up to 40 m tall, bole tall, branchless for up to 25 m, up to 150 cm in diameter, buttresses blunt, bark surface non-fissured, dark grey to yellowish-grey, flaky, outer bark thin, grey, inner bark pinkish-brown, brittle, sapwood pale ochre; buds lanceolate-falcate, glabrous.
Leaves broadly elliptical, 8-13 cm × 3.3-7 cm, base cuneate, acumen up to 5 mm long, secondary veins (7-)9-11 pairs, ascending, glabrous, petiole 2-3 cm long, stipules linear-lanceolate, subacute, inside silky tomentose.
Stamens about 30.
Fruit calyx tube globose to subturbinate, smooth, 2 larger fruit calyx lobes up to 14 cm × 3 cm, 3 shorter ones up to 1 cm × 1 cm.
The tree is harvested from the wild as a source of keruing timber, which is used locally and also traded. It is also often tapped by local people for its oleo-resin, and there is commercial interest in the essential oil that can be obtained from this resin.
Although still locally common in some areas, the tree has been classified as ‘Critically endangered’ in the IUCN Red List of Threatened Species.
Young trees grow best in the shade of the forest, but become increasingly light-demanding as they grow larger.
Members of this genus generally only regenerate naturally in the shade of the forest. Seedlings and saplings can persist in dense forest shade for many years. In their first 2 years the young plants cannot tolerate major openings in the canopy, but after they are well established (about 120cm tall) the canopy can be opened up around them to speed up their growth.
Propagation: Through seeds:
Edible Uses: Not known to us.
The oleo-resins obtained from the tree are used in analgesic liniments. Dipterocarpus species showed Anti-AIDS, cytotoxic, anti-inflammatory, anti-bacterial, anti-fungal and anti-oxidant activities.
An oleoresin is obtained by tapping the tree. It is commonly used by local people for caulking boats; making torches, coating wood as a protection against weather; etc. The resin is obtained by cutting a hole in the trunk near the base (about 90 – 150cm from the ground) and then dipping out the resin with a spoon as it collects there. To prolong the flow, a fire made from dead leaves or brushwood is made in the hole at intervals – this burns off the dried resinous film and allows the resin to flow again.
An essential oil can be distilled from the resin. It is used as a fixative in perfumery and for scenting soaps.
The tree is a source of keruing timber. We have no specific information on the wood, but the general description of keruing timber is as follows:-
The heartwood is light red to red brown or purplish red brown; it is clearly demarcated from the 5 – 7cm wide band of sapwood. The texture is coarse; the grain straight or interlocked. The wood is moderately heavy to heavy; moderately hard; somewhat durable, being resistant to dry wood borers, fairly resistant to fungi but susceptible to termites. It seasons slowly, with a high risk of checking and distortion; once dry it is poorly stable to moderately stable in service. It has a high blunting effect on tools due to the presence of silica, stellite-tipped and tungsten carbide tools are recommended; some species are very resinous and can clog tools; there is occasional tearing on quartersawn wood; nailing and screwing are good, but require pre-boring; gluing is correct, but care is required because of the resin. A general construction timber, it is used in carpentry, panelling, joinery, floors, timber frame houses, boxes and crates, veneer etc
Disclaimer : The information presented herein is intended for educational purposes only. Individual results may vary, and before using any supplement, it is always advisable to consult with your own health care provider.