Aquilaria malaccensis Lamk., Encycl. 1 (1783)

Synonyms
Agallochum malaccense (Lamk.) O.K.
Agallochum malaicense Rumph.
Agallochum secundarium coinamense Rumph.
Aquilaria agallocha Roxb.
Aquilaria agallocha Roxb. ex DC.
Aloexylum agallochum Lour.
Aquilaria agallochum Roxb.
Aquilaria moluccensis Oken
Aquilaria ovata Cav.
Aquilaria secundaria DC
Aquilariella malaccensis (Lamk.) van Tiegh

Description
Tree, up to 20(-49) m tall, with bole up to 60 cm in diameter, usually straight, sometimes fluted or with thick (10 cm) buttresses up to 2 m high; bark smooth, whitish; branchlets slender, pale brown, pubescent, glabrescent. Leaves simple, alternate; petiole 4-6 mm long; blade elliptical-oblong to oblong-lanceolate, 7.5-12 cm x 2.5-5.5 cm, chartaceous to subcoriaceous, glabrous, sometimes pubescent and glabrescent beneath, shiny on both surfaces, base acute, attenuate or obtuse, apex acuminate, acumen up to 2 cm long; veins in 12-16 pairs, rather irregular, often branched, elevated and distinct beneath, curving upward to the margin, plane or obscure above. Inflorescence a terminal, axillary or supra-axillary, sometimes internodal umbel, usually branched into 2-3 umbels, each with about 10 flowers; peduncle 5-15 mm long; pedicel slender, 3-6 mm long; flowers 5-merous, campanulate, 5-6 mm long, green or dirty-yellow, scattered puberulous outside; floral tube nearly glabrous inside, distinctly 10-ribbed, persistent in fruit; calyx lobes 5, ovate-oblong, 2-3 mm long, almost as long as the tube, reflexed, densely puberulous within; petaloid appendages 10, inserted at the throat of the tube, oblong or slightly ovate-oblong, about 1 mm long, slightly incurved, densely pilose; stamens 10, free, emerging from the throat of the tube, filamentous, 1.2-2 mm long, episepalous ones longer than the others; anthers linear, obtuse; pistil included; ovary ovoid, 1-1.5 mm long, 2-celled, densely pubescent; style obscure, stigma capitate. Fruit a loculicidal capsule, obovoid or obovoid-cylindrical, 3-4 cm x 2.5 cm, usually compressed, pubescent, glabrescent, base cuneate, apex rounded; pericarp woody. Seed ovoid, 10 mm x 6 mm including a beak 4 mm long, densely red-haired, bearing from the base a twisted, tail-like, pubescent appendage as long as the seed. Seedling with epigeal germination. [From PROSEA]

Ecology
Commonly found in primary and secondary forest, mainly in plains but also on hillsides and ridges up to 1500 m altitude. It always occurs scattered, in Peninsular Malaysia and north-eastern India at a density of about 2.5 trees/ha. In north-eastern India it occurs up to 1000 m altitude, but grows best in undulating terrain from 200-700 m, with an annual rainfall of 1500-6500 mm, a mean annual maximum temperature of 22-28¡ãC and a mean annual minimum temperature of 14-21¡ãC. In north-eastern India it is found in wet-evergreen and evergreen forest and more rarely in semi-evergreen forest. Aquilaria malaccensis prefers heavy soils developed from gneiss and other metamorphic rocks, but it also grows well on sandy loams developed from sandstone. Mostly along rivers and streams and on ridges with sandy soils.

Uses
Agar wood is the rare and famous, resin-containing heartwood produced from old and diseased trees of several Aquilaria species of which Aquilaria malaccensis, Aquilaria crassna Pierre ex H. Lecomte from Indo-China and Thailand and Aquilaria sinensis (Lour.) Sprengel (synonym Aquilaria grandiflora Benth.) from southern China are most important. In trade a distinction between the wood from these species is rarely made. The fragrance produced by the burning agar wood has been highly valued for thousands of years, and its use as incense for ceremonial purposes in Buddhism, Confucianism and Hinduism is widespread throughout eastern and southern Asia. In Thailand it is put into funeral pyres, while in Japan, the incense is used in tea ceremonies. In the early 19th Century agar wood was part of the tribute paid by Vietnam to the imperial court in Beijing. Wood only partly saturated with resin but still fragrant, and occasionally also the wood remaining after distillation, is made into sticks called 'joss-sticks' or 'agarbattis' which are burnt as incense. Agar-wood oil is an essential oil obtained by water and steam distillation of agar wood. Agar-wood oil is used in luxury perfumery for application in e.g. oriental and woody-aldehydic bases, 'chypres' and 'fougeres'. It produces interesting odour notes with clove oil, e.g. in carnation bases. The oil is so rare and expensive that it is only produced on request. Attars of agar wood are used more widely in the Middle East and India. The silvery inner bark can be removed from the trunk in a single large sheet. It is highly valued for its strength and durability and is made into cloth and ropes. In Assam and Sumatra it is made into writing material, formerly only used for chronicles of important events and religious books. In western, Chinese and Indian medicines the incense is used against cancer, especially of the thyroid gland. In China it is applied as a sedative against abdominal complaints, asthma, colics and diarrhoea, and as an aphrodisiac and carminative. The incense is also used as an insect repellent. Grated wood enters into various preparations used especially during and after childbirth, and to treat rheumatism, smallpox and abdominal pains. Decoctions of the wood are said to have anti-microbial properties, e.g. against Mycobacterium tuberculosis and Shigella flexneri. The timber of undiseased trees, known as 'karas', is very light and is suitable for making boxes, light indoor construction and veneer.

Distribution
India, Burma, Thailand, Peninsular Malaysia, Sumatra, Borneo (Sabah, East-Kalimantan), Philippines.

Local names
Borneo: Alas, Calambac, Ching karas, Gaharu, Galoop, Garu, Gharu, Karas, Kayu gaharu, Kekaras, Kepang, Laroo, Mengkaras, Ngalas, Sigi-sigi, Tabak, Taras gharu, Tengkaras.
English: Agar wood, Malayan aloes-wood, Malayan eaglewood.
French: Bois d'aigle, calambac, calambour.
Indonesia: gaharu, ki karas (Sundanese), mengkaras (Sumatra).
Malaysia: gaharu, tengkaras, karas.
Burma (Myanmar): agar.
Vietnam: tr[aaf]m h[uw][ow]ng.