Gaharu (Malay word for agar wood) is the most expensive
wood in the world. It is valued in many cultures for its
distinctive fragrance, and used extensively in incense
and perfumes. Gaharu is the occasional product of two to
four genera in the family Thymelaeaceae, with Aquilaria
agallocha, Aquilaria crassna and Aquilaria malaccensis
being the three best known species. The name of the
species is derived from the latin word “aquila” meaning
eagle. Gaharu is known throughout many Asian countries
and at least 15 species of Aquilaria trees are known to
produce the much sought-after agar wood. The valuable
wood has been traded for thousands of years throughout
Asia. It used to be commonly found in many tropical
countries, from India to Indonesia (Angela Barden et. al.,
A. malaccensis has been trial planted by the Sabah
Forestry Department in experimental plots at Sook,
Keningau, Segaluid Lokan and Sungai Daling, Sandakan
and thus, this report shall focus on A. malaccensis. The
earliest planting is at Sook which was planted in 1990 with
seeds collected locally from various forest reserves.
Aquilaria malaccensis Lamk
Aquilaria malaccensis, also known as Agallochum (trade
name), belongs to the Thymelaeaceae family. It occurs
from north-eastern India through Myanmar to Peninsular
The Potential of Gaharu as a Plantation Species
Malaysia, Sumatra, Bangka, Borneo and the Philippines.
The tree can grow up to 40 meters in height and reach a
diameter of 60 cm. The tree usually grows straight, but is
sometimes fluted or with thick (10 cm) buttresses up to 2
meters high. A. malaccensis is commonly found in primary
and secondary forests, mainly in plains but also on hillsides
and ridges up to 750 meters altitude. A. malaccensis yields
a soft, lightweight hardwood with a density of about 400
kg/m3 air dry (Chakrabarty et. al., 1994)
A. malaccensis grows best in undulating terrain from
200-700 meters, with an annual rainfall of 1500-6500
mm, a mean annual maximum temperature of 22-280C
and a mean annual minimum temperature of 14-21oC. A.
malaccensis prefers heavy soils developed from gneiss
and other metamorphic rocks, but it also grows well on
sandy loams developed from sandstone. A. malaccensis
is propagated by seed. Fruits harvested for seeds should
be collected when mature but still green. Fruits are
dried in the shade for about 2 days. They then burst and
release the seed. Seeds should be sown immediately,
as it remains viable for only about 1 month. Germination
starts after 10-12 days and is normally complete after 1
month. Seedlings are pricked out into polythene bags 40-
45 days after germination when they are 3-5 cm tall, and
are kept under shade. They are ready for transplanting
when 30-35 cm tall and 10-12 months old (Mabberley, D J,
1997). Transplanting bare rooted seedlings has been tried
successfully in Malaysia.
Field Performance of Locally Grown A. malaccensis
A. malaccensis planted at plot no. 90A Sook reveals a
mean diameter of 19.94 cm and a mean total height of
13.58 meters at the age of 17 years old, representing an
MAI diameter of 1.25 cm per year and an MAI total height
of 0.85 meter per year.
Oyen L P A and Nguyen X D (1999) reported that, in a
plantation in Malaysia, 67 year old trees of A. malaccensis
reached an average height of 27 meters and a diameter of
38 cm. However it was not reported where in Malaysia the
trees were planted!
Formation of Gaharu
Gaharu or agar wood formation is a pathological process
taking place in the stem or main branches where an injury
has occurred. Fungi are involved in the process, but the
process itself is not yet fully understood. Damage by
boring insects is often associated with the infection. It is
believed that the tree is first attacked by a pathogenic
fungus, which causes it to weaken. Infection by a second
fungus causes the formation of agar wood, but it is unclear
whether it is a product of the fungus or the tree. The fungus
implicated in the formation of agar wood in A. malaccensis
is Cytosphaera mangiferae, while Melantos flavolives is
assumed to play a similar role in A. sinensis. A. malaccensis
forms an association with endotrophic mycorrhizal fungi.
In natural forests, only 7-10% of the trees are infected by
the fungus (Ng. et al, 1997). A common method in artificial
forestry is to inoculate the trees with the fungus.
A 17-year old Aquilaria malaccensis at Sook with a DBH of
31.1 cm and height of 19 meters. Photo by Julius Kodoh.
Agar wood is the rare and famous, resin containing
heartwood produced from old and diseased trees of several
Aquilaria species of which A. malaccensis, A. crassna and
A. sinensis are most important. 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. The
wood is only partly saturated with resin but still fragrant,
and occasionally, 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,
which is used in luxury perfumery. The incense is also
used as an insect repellent and for medicines. The timber
of undiseased trees, known as ‘karas’, is very light and is
only suitable for making boxes, light indoor construction
and veneer [Angela Barden et al (2000)].
Agar wood has become a precious commodity. According
to Angela Burden et al (2000), based on available trade
data, Indonesia and Malaysia appear to be the main
sources of agarwood (from all species) in international
trade. CITES reported that exports of A. malaccensis from
Indonesia topped 920 t from 1995 to 1997, although CITES
argue that it might include other species of Aquilaria. Over
340 t of A. malaccensis were reported as exported from
Peninsular Malaysia during the same period. Angela
Burden et al (2000) also reported that according to
Sarawak’s CITES Management Authority, nearly 530 t
of A malaccensis were exported from Sarawak alone in
1998. Although overall trade volume may appear small in
“timber trade” terms, but they are not small in monetary
terms. Most of agarwood in international trade is destined
for consumers in the Far and Middle East, with key final
export destinations from 1995 to 1997 being Saudi Arabia,
the United Arab Emirates, Hong Kong and Taiwan.
Chakrabarty et al (1994) stated that the lowest grade
of Malaysian agarwood (not necessarily A. malaccensis)
could be obtained for USD19/kg in the Middle East. The
high grades, normally reserved for exclusive buyers, can
cost up to USD9589/kg. More expensive grades are also
available and can sell for as much as USD27400/kg.
The A. malaccensis tree is comparative to gold and is
becoming very rare in the wild due to illegal extraction.
Thus, the species has been CITES listed in Appendix II.
The listing subjects the species to limited commercial use
and stringent monitoring through a permit system. Under
CITES rules, the Management Authority will issue CITES
Export Permit to exporters of gaharu which originate from
Malaysia, CITES Import Permit to importers of gaharu,
and CITES Re-Export Certificate to traders of this species
which originate from other countries. The Importers are
requested to furnish the CITES Export Permit from the
exporting country before the Management Authority can
issue the CITES Import Permit.
The extremely high prices paid for high quality agar wood
and for the essential oil and the indiscriminate felling of
diseased and healthy trees threaten natural stands of
Aquilaria including A. malaccensis to extinction. Research
into possibilities of artificial induction and stimulation of
agar wood formation is therefore urgently required and
may offer high economic returns, especially as trials
indicate that management of plantations presents no
great difficulties. Unless such methods are developed, A.
malaccensis may soon be extinct.
Today, gaharu is becoming more popular in Malaysia.
Projects are currently underway in some countries in
Southeast Asia to infect cultivated Aquilaria trees artificially
to produce gaharu in a sustainable manner. In Malaysia,
various Research Institutions are conducting research and
development on Aquilatria trees. The Forest Research
Centre of the Sabah Forestry Department has recently
undertaken a collaborative project to artificially inoculate
gaharu trees to induce the formation of agarwood in one
of the planted Gaharu plots. What remains to be seen is
the success of this project, but if it proves to be successful,
it will be a breakthrough in terms of its socio-economic
potential as well as in protecting the remaining gaharu
trees available in the wild.
Angela Barden, Noorainie Awang Anak, Teresa Mulliken
and Michael Song (2000), Heart Of The Matter: Agarwood
Use And Trade And Cites Implementation For Aquilaria
Chakrabarty K, Kumar A and Menon V (1994), Trade in
Agarwood. Traffic India and WWF-India, New Delhi.
Mabberley D J (1997), The Plant Book, The Press
Syndicate of the University of Cambridge, UK, 858pp.
Ng L.T., Chang Y.S. and Kadir A.A. (1997), A Review on
Agar (gaharu) producing Aquilaria species, Journal of
Tropical Forest Products 2(2): 272-285.
Oyen L.P.A and Nguyen Xuan Dung (Editors), 1999. Plant
Resources of South-East Asia No 19. Essential-Oil Plants.
Backhuys Publishers, Leiden, the Netherland.