KEDONDONG

INTRODUCTION

The Standard Malaysian Name for the timbers of the family Burseraceae. Vernacular names applied include kedondong (Peninsular Malaysia and Sabah), with various epithets, kembayu (Sabah), kerantai (Peninsular Malaysia and Sabah), pamatadon (Sabah), seladah (Sarawak) and senggeh (Peninsular Malaysia). Major species include Canarium apertum, C. littorale, C. pseudosumatranum; Dacroydes costata, D. incurvata; Santiria apiculata, S. conferta, S. tomentosa; Scutinanthe brunnea; and Triomma malaccensis. The sapwood is usually lighter in colour than the heartwood and not well defined from the heartwood. However, in Santiria griffithii and S. rubiginosa, the sapwood is well defined. The heartwood varies in colour from light yellow in Canarium apertum to yellow-green-brown in S. griffithii and S. rubiginosa to the common light red-brown and deep red-brown of the other species.

Also known as Kedondong (Brunei); Talat (Cambodia); Kaunicina (Fiji); Karapu kongiliam and White dhup (India); Bayung, Bosi, Kembajau, Kenari, Kerantai, Merasam putih, Merdondong, Ranggarai, Resung and Unggit (Indonesia); Canarium and Galip (Papua New Guinea); Dao, Gisaun, Kamingi, Kalaua, Pagsahingin, Pili and Pilingliitan (Philippines); Ma´┐Żali (Samoa Islands); Kekuna (Sri Lanka); Ma Koem (Thailand); and Cham (Vietnam).

DENSITY

The timber is a Light Hardwood with a density of 495-980 kg/m3 air dry and average density of 705 kg/m3 air dry.

NATURAL DURABILITY

Jackson (1965) classified this timber as not durable if exposed to weather or in direct contact with the ground. The average service life for the species tested is 1.2 years. The sapwood of the timber is liable to heavy attack by powder-post beetles due to its high starch content. It was reported by Desch (1941) that the heartwood can be readily attacked by drywood termites.

PRESERVATIVE TREATMENT

The timber of kedondong has been found to be very difficult to treat with preservatives.

TEXTURE

Texture is fairly fine and even, with shallowly or deeply interlocked grain.

STRENGTH PROPERTIES

The timber falls into Strength Group C (Engku, 1988b) or SG 5 (MS 544:Part 2:2001).

Strength Properties of Kedondong
Timber Species Test Condition Modulus of Rupture (MPa) Modulus of Elasticity (MPa) Compression parallel to grain (MPa) Compression perpendicular to grain (MPa) hear strength(MPa)
C. littorale f. rufum Green - - 29.6 2.94 7.2
Air dry - - - - -
C. megalanthum Green 65 11,700 35.0 4.62 9.3
Air dry 81 12,900 43.7 6.41 11.8
S. laevigata Green 64 11,200 31.8 - 8.0
Air dry 81 12,100 43.1 - 10.9

MACHINING PROPERTIES

The working quality of the timber is variable, ranging from easy to very difficult to work, due to the presence of silica and deeply interlocked grain. Planing is easy to slightly difficult and a smooth surface is often obtained although in some cases, severe picking-up of the grain has been noted.

Machining Properties of Kedondong
Species Test Condition Sawing Planing Boring Turning
Re-sawing Cross Cutting Ease of planing Quality of finish Ease of boring Quality of finish Ease of turning Quality of finish
C. littorale, f. rufum Green easy easy easy smooth easy slightly rough - -
Air dry slightly difficult slightly difficult moderately easy moderately smooth easy slightly rough difficult smooth
P. stellata Green difficult very difficult easy moderately smooth easy smooth - -
Air dry very difficult very difficult slightly difficult rough very difficult rough difficult moderately smooth
S. laevigata Green difficult difficult slightly difficult moderately smooth difficult smooth to slightly rough - -
Air dry very difficult very difficult slightly difficult moderately smooth difficult slightly rough slightly difficult moderately smooth

NAILING PROPERTY

Nailing property is good.

AIR DRYING

Seasoning properties for some species are summarised below:

Species Time to air dry (months) Remarks
13 mm thick boards 38 mm thick boards
Canarium littorale, f. rufum 3.5 4 Fairly slow drying; powder-post beetle attacks; slight cupping, bowing, splitting and staining.
S. laevigata 2 6 Fairly slow drying; powder-post beetle attacks; slight cupping, end-checking and surface-checking.
S. tomentosa 3 5 Fairly slow drying; powder post-beetle and sapstain fungi attacks.

KILN-DRYING

Kiln Schedule J is recommended for Canarium spp. 25 mm thick boards take 6 days to dry.

Kiln Schedule C
Moisture Content (%) Temperature (Dry Bulb) Temperature (Wet Bulb) Relative Humidity (%) (approx.)
°F °C °F °C
Green 135 57.0 123 50.5 70
50 135 57.0 119 48.0 60
40 140 60.0 118 47.5 50
30 150 65.5 121 49.0 40
20 170 76.5 127 53.0 30

SHRINKAGE

The shrinkage characteristics for some species are summarised below:

Species Shrinkage (%) (Green to air dry) Remarks
Radial Tangential
C.littorale, f. rufum 2.4 4.1 Very high shrinkage
S. laevigata 1.8 3.2 High shrinkage
S. tomentosa 2.4 3.5 High shrinkage

MOVEMENT IN SERVICE

The movement of seasoned timber is classified under Type II.

DEFECTS

The defects that are associated with the timbers of kedondong are the presence of knots and pin-holes on the surface. The timber of several species appears to be very liable to attack by blue-stain fungi soon after felling (Desch, 1941).

USES

The timber is suitable as a general utility timber for posts, beams, joists, rafters, medium heavy structures, railway sleepers, vehicle bodies (framework and floor boards), planking, cladding, plywood, tool handles (non-impact), particleboard, flooring, furniture, packing boxes and crates as well as pallets (expendable and permanent light duty types).

REFERENCES

  1. Ahmad Shakri Mat Seman. 1983. Malaysian Timbers - Kedondong. Timber Trade Leaflet No. 73. The Malaysian Timber Industry Board and Forest Research Institute Malaysia, Kuala Lumpur. 9 pp.
  2. Desch, H. E. 1941. Manual of Malayan Timbers. Malay. For. Rec. No. 15.
  3. Engku Abdul Rahman Chik. 1998b. Basic and Grade Stresses for Strength Groups of Malaysian Timbers. Malayan Forest Service Trade Leaflet No. 38. The Malaysian Timber Industry Board and Forest Research Institute Malaysia, Kuala Lumpur. 13 pp.
  4. Jackson, W. F. 1965. Durability of Malayan Timbers. Malay. For. Ser. Trade Leaflet No. 28.
  5. Menon, P. K. B. 1986. Uses of Some Malaysian Timbers. Revised by Lim, S. C. Timber Trade Leaflet No. 31. The Malaysian Timber Industry Board and Forest Research Institute Malaysia, Kuala Lumpur. 48 pp.
  6. MS 544:Part 2:2001. Code of Practice for the Structural Use of Timber: Permissible Stress Design of Solid Timber.
  7. ong, T. M. 1982. A Dictionary of Malaysian Timbers. Revised by Lim, S. C. & Chung, R. C. K. Malayan Forest Records No. 30. Forest Research Institute Malaysia, Kuala Lumpur. 201 pp.