Some Malayan hardwoods

Part One

T HE classification of Malayan I timbers falls broadly into the four following categories: (a) heavy hardwoods, (b) medium hardwoods, (c) light hardwoods, (d) softwoods. For the purposes of this article, we will be discussing the l0 primary heavy hardwoods that are listed in the official Malayan Grading Rules for Sawn Hardwood Timber (reprinted 1963) issued by The Forest Department.

The heavy hardwoods listed are:

(r) BALAU

Balau is made up of fairly uniform wood of several species of Shorea the more common of which are S. atrinervosa, S. foxworthyi, S. glauca, S laevis and S. macwelliana. It is a very hard, heavy, strong and durable wood superior in all respects to Sal /S. robusta) of India and is one of the best heavy constructional woods of Malaya. Similar timbers in North Borneo and the Philippines are marketed under the names Selangan Batu and Yakal respectively, but these names also include the heavy timbers of Hopea which are known separately in Malaya as Giam, see below.

The wood is not unduly difficult to work but care is necessary in seasoning small dimension stock because shrinkage is high and the wood is liable to split in drying. It is generally free of defects.

Story at a Glance

Part one of a two part look at ten species of heavy hardwood from the Southeast Asian nation of Malaya . included are general description, shrinkage, turn ing, etc.

General desciption of the wood:Sapwood is moderately well defined and lighter in colour than heartwood. The colour of freshly cut heartwood is yellow-brown, brown, or brown with a reddish tinge weathering ultimately to a deeper shade of brown or reddish dark brown. Planed surface is not particularly lustrous but is by no means dull. The grain is interlocked, often giving rise to faint stripe figure: texture is moderately fine and even. Resin canals usually with white contents, occur characteristically in concentric lines on the end surface but the wood is not resinous.

(2) RED BALAU

Red Balau is similar to Philipphe Guijol it is the product of a few species of Shorea, the most common of which are S. guiso and S. kunstlen. The timber is hard and heavy and sufficienfly strong and durable for all heavy construction but compared to Balau it is inferior in both strength and durability. It is comparatively easy to work but care is necessary in seasoning because shrinkage is high and it is therefore liable to split when drying.The wood generally has no serious defects.

General description of the wood:Sapwood well defined. Heartwood redbrown or purple brown in color when freshly cut weathering to a darkbrown. Surface is rather dull (without lustre). The grain is interlocked often giving rise to stripe figure. Texture rather coarse but even. Resin canals with white contents occur characteristically in concentric lines on the end surface but the wood is not resinous. (Only the darker colour and coarser texture differentiate this wood from Balau).

(3) BrTrS

Bitis, produced mainly by Maduca utilis, (some other species are known as Nyatoh batu) is a very hard, very heavy and durable wood. Though very hard to work it planes and turns to a very good finish. Its seasoning properties are not good: it dries slowly but as the shrinkage is high it is liable to surface checking and end splitting. It is generally free of defects.

General description of the wood:Sapwood is well defined. Heartwood is red-brown or chocolate brown in color. Surface is not lustrous. The grain is straight or only slightly interlocked and the texture is fine andeven. The wood lathers freely when rubbed with water. It has a bitter taste.

(4) CHENGAL

Chengal, the product of a single species Balanocarpus heimii is the most popular Malayan wood for heavy permanent structures and for other uses where durability is of prime concern. It is hard, heavy and strong and is one of the most durable woods of the world (except in sea water exposed to marine borers). It is one of the easiest Heavy Hardwoods to work. It seasons without degrade but is slow drying. The only flaw in this wood is the numerous "pin holes" which are the galleries of dead Ambrosia beetles that attack almost all living trees of Chengal. Except on aesthetic grounds this is not objectionable because the strength of the wood is never significantly affected by these pin holes.

General description of the wood:Sapwood is well defined. When freshly sawn the heartwood is yellow-green in color weathering ultimately to a dark tan brown. Wood is moderately lustrous and has very prominent ripple marks. The grain is interlocked giving rise to strip figure; texture is moderately fine and even. Resin canals with white contents occur characteristically in concentric lines on end surface but the wood is not resinous.

(Continued next month)