Garu and Chandan
H.N. Ridley, Government Botanist for the Straits Settlements, published this article in 1901 to resolve persistent taxonomic confusion surrounding the two most important incense woods of the Malay Peninsula—Garu (Aquilaria malaccensis) and Chandan (a new species he described as Aquilaria hirta). The article combines formal botanical description with a survey of the historical, etymological, and commercial literature on these woods, arguing that the Malaccan Garu is distinct from the Indian A. agallocha and that the name “Chandan” is applied to at least two unrelated plants.
Summary
Ridley opens by noting that despite the long commercial history of incense woods in the East, the trees producing them remain poorly known to botanists. He provides a full morphological description of Aquilaria malaccensis, the source of Garu (also called Calambac, Tuikaras, and Karas), a 70–80-foot tree found in dense forests from Penang through Johor to Sumatra and Borneo. A significant portion of the article is devoted to disentangling the taxonomic confusion between this species and the Indian A. agallocha, which had been conflated in earlier literature. Ridley argues on the basis of floral structure—particularly the number and arrangement of scales at the mouth of the corolla tube, the shape of the pistil, and the panicled versus solitary arrangement of umbels—that the Malaccan plant is clearly distinct (pp. 73–75).
The second major contribution is the description of Aquilaria hirta, a new species Ridley identified from specimens collected at Bukit Pengaram in Johor (nearly 1,000 feet altitude) and Kranji in Singapore. The tree is much smaller than Garu (about 30 feet, four inches in diameter) and is distinguished by the persistent silky hairiness of its leaves, flowers, and fruit—features absent in all previously described Aquilaria species. The aromatic heartwood is a dusky blackish-grey, contrasting with the white sapwood (pp. 78–79).
The article closes with a discussion of “Pahang Chandan,” which Ridley identifies not as an Aquilaria at all but as Wikstroemia Candolleana, a small mountain tree of the same order (Thymeleaceae) growing at 4,000–5,000 feet. This finding underscores the broader problem of nomenclatural confusion: the Malay term “Chandan” is applied to at least two botanically unrelated plants, and the trade in incense woods is further complicated by widespread adulteration, including the practice of scenting decayed wood with Calambac shavings to pass it off as genuine (pp. 80–82).
Key Findings
- Aquilaria malaccensis (Garu) is a 70–80-foot tree; the aromatic resinous wood is found only in the hollow centres of certain old, apparently injured specimens, while the ordinary wood is soft, white, and commercially worthless (p. 74).
- The new species Aquilaria hirta (Chandan) is a slender tree of about 30 feet and four inches diameter, distinguished from all other Aquilaria by the persistent silky pubescence on leaves, flowers, and fruit; it occurs in dense forest at Kranji, Singapore, and Bukit Pengaram, Johor (pp. 78–79).
- Good Garu commanded a price of four hundred dollars per picul at the time of writing (p. 77).
- Garcia de Orta, who visited Malacca around 1534, provided the first good European account of the wood, naming it “Garo” with the best grade “Calambac,” and noted that the Chinese brought it from Malacca and Sumatra (p. 75).
- Wikstroemia Candolleana, the true source of “Pahang Chandan,” is a small tree of 6–10 feet growing at 4,000–5,000 feet altitude in the Gunong Benom range and elsewhere; its aromatic heartwood is greyish-black and resembles that of A. hirta (pp. 80–81).
- Ridley lists eight known Aquilaria species with their distributions, and excludes three previously included names (A. bancana, A. macrophyllus, A. pentandra) as misapplied (p. 80).
Conclusion
Ridley’s definitive takeaway is that the incense woods of the Malay Peninsula are far more taxonomically diverse and nomenclaturally confused than the trade literature suggests. The name “Chandan” alone covers at least two unrelated genera, the Garu trade is riddled with adulteration, and several species remain undescribed or unrecovered from their original localities—particularly in Cochin China and Siam, where no botanist has yet collected an Aquilaria since Loureiro’s fragmentary specimens of the eighteenth century.
Context
- Ridley held the position of Government Botanist for the Straits Settlements; the article reflects the colonial scientific infrastructure of botanical surveys and specimen collection that underpinned his work, with material drawn from his own herbarium and from collectors operating under colonial administrative auspices.
- The article draws on a range of primary and secondary sources including Rumphius’s Herbarium Amboinense, Garcia de Orta’s Coloquios, Pomet’s Histoire des Drogues, and earlier MBRAS publications by Bland and Skeat, situating itself within the Straits Branch’s ongoing programme of documenting the natural history of the Peninsula.