Botanical names: Shorea spp. Principally S. glauca, S. laevis, S.
albida, S. seminis, S. maxwelliana, S. astylosa.
Family name: Dipterocarpaceae
Local names: Selangan batu No.1, alan batu (mature wood), alan
bunga (juvenile wood), meraka, empenit, sengawan, alan (Sabah and Sarawak),
yakal, gisok (Philippines), belangeran (Borneo), empenit thitya (Burma),
chan, teng (Thailand), bangkirai (Indonesia), sen, ca-chac (Vietnam), yellow
Note: The name balau is also used for some species of Hopea
Tree description and natural occurrence
Medium to large hardwoods, often buttressed, with a straight cylindrical
bole between 30 and 50 m long. These Shorea spp. grow across a diversity of
site types in Indonesia, Malaysia, Thailand and the Philippines.
Yellowish brown heartwood, sapwood distinctly paler.
Varies from straight to interlocked. Interlocking grain
produces striped figure on quarter-sawn material. Texture moderately coarse
900 kg/m3 at 12 % moisture content; approximately 1.1 m3 of
seasoned, sawn timber per tonne.
. S3 unseasoned, (SD3) seasoned.
F8, F11, F14, F17 (unseasoned); F14, F17, F22, F27
(seasoned) when visually stress-graded in accordance with AS2082-2000,
'Visually stress-graded hardwood for structural purposes'.
Joint groups. J2 unseasoned; JD2 seasoned.
Shrinkage to 12% MC.
Shrinkage rates varies considerably between
Class 1 - life expectancy less than 40 years.
Class 2 - life expectancy 15 to 25 years.
Untreated sapwood is susceptible to lyctine
Sapwood readily accepts preservative impregnation.
Care required when drying to avoid splits, checks, and
Hard (rated 2 on a 6 class scale) in relation to resistance
and ease of working with hand tools.
Resinous material gums up cutting edges, otherwise
relatively easy to machine and turn.
Pre-boring recommended when nailing.
As with most high-density species machining and surface
preparation should be done immediately before gluing.
Satisfactory in relation to painting, staining and
Framing, flooring, decking, linings, joinery,
Boat building, vats, casks.
Well-defined and paler than heartwood.
Yellow brown, brown, reddish brown
Moderately coarse, even, grain interlocked, hard to cut
across end grain; end cut generally shiny; both species show a degree of
lustre on a dressed surface.
Mostly solitary with a few radial or oblique groups, medium
size, even and diffuse distribution. Tyloses numerous. Vessel lines
Apotracheal - consisting mainly of irregular spaced bands
and occasional short tangential lines or diffuse strands. Paratracheal -
often as incomplete vasicentric strands around the vessels, barely visible
by hand lens, scant to well-defined aliform.
Fine, generally inconspicuous on the radial surface.
Burning splinter test.
A match size splinter burns to an ash.
Generally filled with white resin, smaller than
the vessels, arranged in concentric formation.
For information on technical terms consult Timber Species note No.1.