Balau

Introduction

The hard, heavy timber species of shorea occurring in South East Asia are grouped under common trade names peculiar to the area. Thus selangan batu is the name used in Sabah, Brunei and Sarawak, while balau is used to describe the heavy Malaysian species.

Environmental

Many species of shorea appear on the IUCN Red List of Threatened Species and are classified as:

• CR – Critically Endangered: at very high risk of extinction in the wild
• EN – Endangered: at high risk of extinction in the wild
• VU – Vulnerable: at risk of extinction

[Information courtesy of Timbmet Ltd]

Distribution

Selangan batu is produced by several species, principally S. laevis and S seminis. Red selangan batu is principally S. guiso. Balau is generally separated into two types in Malaysia, ie, balau and red balau. Balau is produced mainly from shorea atrinervosa, S. elliptica, S. foxworthyi, S. glauca, S. laevis, S. maxwelliana and S. submontana. Red balau is produced mainly from S. guiso, S. kunstleri, S. collina, and S. ochrophloia.

The timber

Selangan batu is a yellowish-brown timber with interlocked grain, and a coarse, but even texture. According to species, durable to very durable. Balau is a yellowish-brown, brown, or reddish-brown timber vvith interlocked grain, and a moderately fine and even texture. It is classified in Malaysia as being very durable. Red balau is a purplish-red or dark red-brown timber, with an interlocked grain, and a coarse but even texture. It is classified in Malaysia as being less durable than balau, ie moderately durable. Red selangan batu (Sabah), and alan, or meraka alan (Saravvak and Brunei) are approximately equal in colour and characteristics to red balau.

Drying

Difficult to dry, slow drying with a tendency to end split, warping is variable.

Strength

All the species mentioned have hard, heavy and strong timbers with strength properties similar to those of greenheart.