View source for Agarwood

{{Short description|Fragrant wood of some Thymelaeoideae}}
{{redirect|Aloes||aloe (disambiguation)}}
{{Use dmy dates|date=August 2019}}
{{Use British English|date=March 2012}}
[[File:Agarwood.JPG|thumb|Cultivated aloes/agar wood]]

'''Agarwood''', '''aloeswood''', '''eaglewood''', '''gharuwood''', commonly referred to as '''oud''' or '''oudh''' (from {{langx|ar|عود|translit=ʿūd}}, {{IPA|ar|ʕuːd|pron}}), is a fragrant, dark and [[resin]]ous [[wood]] used in [[incense]], perfume, and small [[Woodworking|hand carvings]].

It forms in the [[heartwood]] of ''[[Aquilaria]]'' trees after they become infected with a type of ''[[Phaeoacremonium]]'' mold, ''P. parasitica''. The tree defensively secretes a resin to combat the fungal infestation. Prior to becoming infected, the heartwood mostly lacks scent, and is relatively light and pale in colouration. However, as the infection advances and the tree produces its fragrant resin as a final option of defense, the heartwood becomes very dense, dark, and saturated with resin. This product is harvested, and most famously referred to in [[cosmetics]] under the scent names of ''oud'', ''oodh'' or ''aguru''; however, it is also called ''aloes'' (not to be confused with the [[succulent plant]] [[genus]] ''[[Aloe]]''), ''agar'' (this name, as well, is not to be confused with the edible, [[algae]]-derived thickening agent [[agar agar]]), as well as ''gaharu'' or ''jinko''. With thousands of years of known use, and valued across [[Hinduism|Hindu]], [[Buddhism|Buddhist]], [[Islam|Muslim]] and [[Chinese people|Chinese]] cultures, oud is prized in Middle Eastern and South Asian cultures for its distinctive fragrance, utilized in [[colognes]], [[incense]] and [[perfumes]].

[[File:Agarwood.jpg|thumb|Uninfected aquilaria wood lacking the dark resin]]

One of the main reasons for the relative rarity and high cost of agarwood is the depletion of wild sources.<ref name="Broad">Broad, S. (1995) "Agarwood harvesting in Vietnam" ''TRAFFIC Bulletin'' 15:96</ref> Since 1995, the [[CITES|Convention on International Trade in Endangered Species of Wild Fauna and Flora]] has listed ''[[Aquilaria malaccensis]]'' (the primary source) in its [[Appendix II|Appendix II (potentially threatened species)]].<ref name="CITES1">[http://www.cites.org/eng/notif/2005/025.pdf CITES (25 April 2005) "Notification to the Parties" No. 2005/0025] {{Webarchive|url= https://web.archive.org/web/20070930014501/http://www.cites.org/eng/notif/2005/025.pdf |date= 30 September 2007 }}. (PDF) . Retrieved on 22 July 2013.</ref> In 2004, all ''Aquilaria'' species were listed in Appendix II; however, a number of countries have outstanding reservations regarding that listing.<ref name="CITES1"/>

The varying aromatic qualities of agarwood are influenced by the species, geographic location, its branch, trunk and root origin, length of time since infection, and methods of harvesting and processing.<ref name=":0">{{Cite journal|last1= López-Sampson|first1= Arlene|last2= Page|first2= Tony|date= 20 March 2018|title= History of Use and Trade of Agarwood|journal= Economic Botany|volume= 72|issue= 1|language=en|pages= 107–129|doi= 10.1007/s12231-018-9408-4|bibcode= 2018EcBot..72..107L|s2cid= 49875414|issn= 0013-0001 |url= https://researchonline.jcu.edu.au/58720/1/58720_L%C3%B3pez-Sampson%20and%20Page_2018.pdf}}</ref> Agarwood is one of the most expensive woods in the world, along with [[Dalbergia melanoxylon|African blackwood]], [[sandalwood]], [[pink ivory]] and [[ebony]].<ref>{{cite web | title= Top 10 Most Expensive Woods in the World | website= Salpoente Boutique | date= 18 November 2016 | url= http://renesabino.com/luxury-blog/top-10-expensive-woods-world/ | access-date= 19 September 2020 | archive-date= 27 July 2020 | archive-url= https://web.archive.org/web/20200727065034/http://renesabino.com/luxury-blog/top-10-expensive-woods-world/ | url-status= dead }}</ref> First-grade agarwood is one of the most expensive natural raw materials in the world,<ref>{{cite web |title= First-grade agarwood can cost as much as $100,000 per kilogram. Why is it so expensive? |author= Andy Ash |url= https://www.businessinsider.com/why-agarwood-is-so-expensive-oud-vietnam-2020-8 |publisher=[[Business Insider]] |date= August 27, 2020 |access-date= September 17, 2020}}</ref> with 2010 prices for superior pure material as high as US$100,000/kg, although in practice adulteration of the wood and oil is common, allowing for prices as low as US$100/kg.<ref name="chem-rev">{{cite journal|last1= Naef|first1= Regula|title= The volatile and semi-volatile constituents of agarwood, the infected heartwood of Aquilaria species: a review|journal=Flavour and Fragrance Journal|date=March 2010 |volume= 26|issue= 2|pages= 73–87|doi= 10.1002/ffj.2034}}</ref> A wide range of qualities and products come to market, varying in quality with geographical location, botanical species, the age of the specific tree, cultural deposition and the section of the tree where the piece of agarwood stems from.<ref name="archiv.ub.uni-heidelberg.de">Dinah Jung, [http://archiv.ub.uni-heidelberg.de/volltextserver/12039/ ''The Value of Agarwood: Reflections upon its use and history in South Yemen''], Universitätsbibliothel, Universität Heidelberg, 30 May 2011, (PDF) p. 4.</ref>

==History==
The odour of agarwood is complex and pleasing,<ref>International Journal of Pharmaceutical and Life Sciences, ISSN 2305-0330, Volume 2, Issue 1: January 2013)</ref> with few or no similar natural analogues. In the perfume state, the scent is mainly distinguished by a combination of "oriental-woody" and "very soft fruity-floral" notes. The incense smoke is also characterised by a "sweet-balsamic" note and "shades of vanilla and musk" and amber.<ref name="archiv.ub.uni-heidelberg.de"/> As a result, agarwood and its [[essential oil]] gained great cultural and religious significance in ancient civilizations around the world. Over 3,000 years ago, the [[ancient Egyptians]] used agarwood incense in their funeral rites.<ref>{{Cite book |last1=Snelder |first1=Denyse J. |url=https://books.google.com/books?id=LmA_5zxDSRkC&dq=agarwood+ancient+Egypt&pg=PA248 |title=Smallholder Tree Growing for Rural Development and Environmental Services: Lessons from Asia |last2=Lasco |first2=Rodel D. |date=2008-07-19 |publisher=Springer Science & Business Media |isbn=978-1-4020-8261-0 |language=en}}</ref> It was described as a fragrant product as early as 1400 BCE in the [[Vedas]] of [[India]].<ref>{{Cite journal |last1=López-Sampson |first1=Arlene |last2=Page |first2=Tony |date=2018-03-01 |title=History of Use and Trade of Agarwood |journal=Economic Botany |language=en |volume=72 |issue=1 |pages=107–129 |doi=10.1007/s12231-018-9408-4 |bibcode=2018EcBot..72..107L |s2cid=255560778 |issn=1874-9364|doi-access=free }}</ref>

In the [[Hebrew Bible]], "trees of lign aloes" are mentioned in [[The Book of Numbers]] 24:6<ref>Numbers 24:6, KJV</ref> and a perfume compounded of aloeswood, [[myrrh]], and [[Cassia bark|cassia]] is described in Psalms 45.<ref name=Psalms>Psalms 45: "All thy garments smell of myrrh, and aloes, and cassia, out of the ivory palaces, whereby they have made thee glad."</ref>

In the [[Gospel of John]], [[Jesus]]’s body is prepared for burial by binding it in linen wrappings with seventy-five pounds of aloes and [[myrrh]] (John 19:39).

[[File:Qing-Agarwood-Rosary.jpg|thumb|Antique agarwood beads with inlaid gold, late Qing dynasty, China. Adilnor Collection, Sweden.]]

[[Dioscorides]] in his book ''[[De materia medica]]'' (50 to 70 CE) described several medical qualities of agarwood (Áγαλλοχου) and mentioned its use as an incense. Even though Dioscorides describes agarwood as having an astringent and bitter taste, it was used to freshen the breath when chewed or as a decoction held in the mouth. He also writes that a root extract was used to treat stomach complaints and dysentery as well as pains of the lungs and liver.<ref name=":0" /> Agarwood's use as a medicinal product was also recorded in the [[Sahih Muslim]], which dates back to approximately the ninth century, and in the [[Ayurvedic]] medicinal text the [[Susruta Samhita]].<ref>{{Cite book|last1=Barden |first1=Angela |last2=Anak |first2=Noorainie Awang |last3=Mulliken |first3=Teresa |last4=Song |first4=Michael |year=2000 |title=Heart of the Matter: Agarwood Use and Trade and CITES Implementation for ''Aquilaria malaccensis'' |location=Cambridge, England |publisher=Traffic International |page=7 |isbn=978-1-85850-177-2 |url=http://www.traffic.org/forestry-reports/traffic_pub_forestry7.pdf |archive-url=https://web.archive.org/web/20081123123800/http://www.traffic.org/forestry-reports/traffic_pub_forestry7.pdf |archive-date=23 November 2008 |url-status=live }}</ref>

As early as the third century CE in ancient Viet Nam, the Chinese [[chronicle]] ''Nan zhou yi wu zhi'' (Strange things from the South) written by Wa Zhen of the Eastern [[Wu (state)|Wu Dynasty]] mentioned agarwood produced in the Rinan commandery, now Central [[Vietnam]], and how people collected it in the mountains.
During the sixth century CE in Japan, in the recordings of the ''[[Nihon Shoki]]'' (The Chronicles of Japan) the second oldest book of classical Japanese history, mention is made of a large piece of fragrant wood identified as agarwood. The source for this piece of wood is claimed to be from [[Pursat Province|Pursat, Cambodia]] (based on the smell of the wood). The [[Ranjatai (wood)|famous piece of wood]] still remains in Japan today and is showcased less than 10 times per century at the [[Nara National Museum]].
[[File:RanJyaTai Shosoin.JPG|thumb|''[[Ranjatai]]'', 8th century, currently held by the [[Shōsōin]], [[Tōdai-ji]], [[Nara, Japan]]]]
Agarwood is highly revered in Hinduism, Buddhism, and [[Chinese folk religion]].<ref name=":0"/><ref>[[Monica Furlong|Furlong, Monica]] (1986). ''Zen Effects: the Life of Alan Watts''. Houghton Mifflin. p. 196. {{oclc|13821191}}. {{ISBN|9780395353448}}.</ref>

Starting in 1580 after [[Nguyễn Hoàng]] took control over the central provinces of modern Vietnam, he encouraged trade with other countries, specifically China and Japan. Agarwood was exported in three varieties: Calambac (kỳ nam in Vietnamese), trầm hương (very similar but slightly harder and slightly more abundant), and agarwood proper. A pound of Calambac bought in [[Hội An]] for 15 [[taels]] could be sold in [[Nagasaki, Nagasaki|Nagasaki]] for 600 taels. The [[Nguyễn Lords]] soon established a [[Legal monopoly|Royal Monopoly]] over the sale of Calambac. This monopoly helped fund the Nguyễn state finances during the early years of the Nguyen rule.<ref>Li, Tana (1998) ''Nguyễn Cochinchina: southern Vietnam in the seventeenth and eighteenth centuries'', Southeast Asia Program Publications, Ithaca, New York, p. 79, {{ISBN|0-87727-722-2}}</ref>
Accounts of international trade in agarwood date back as early as the thirteenth century, with India being one of the earliest sources of agarwood for foreign markets.<ref>{{Cite web|url=https://scroll.in/article/898749/facing-extinction-indias-scented-agarwood-is-finding-ways-to-grow-in-home-gardens-polluted-fields|title=Facing extinction, India's scented agarwood is finding ways to grow in home gardens, polluted fields|first=Sahana|last=Ghosh|website=scroll.in|date=25 October 2018 }}</ref>

[[Xuanzang]]'s travelogues and the ''[[Harshacharita]]'', written in seventh century AD in Northern India, mentions use of agarwood products such as 'Xasipat' (writing-material) and 'aloe-oil' in ancient [[Assam]] (Kamarupa). The tradition of making writing materials from its bark still exists in [[Assam]]. It is still used in traditional Chinese [[herbal medicine]] where it goes by the name of Chén Xiāng - 沉香 - Literally meaning 'sinking fragrance'. Its earliest recorded mention is from the Miscellaneous Records of Famous Physicians, 名医别录, Ming Yi Bie Lu,  ascribed to the author Táo Hǒng-Jǐng c.420-589.<ref>Chinese Herbal Medicine: Materia Medica Revised Edition
by Dan Bensky  (Author), Andrew Gamble (Compiler), {{ISBN|0939616157}}</ref>

== Etymology ==
The word Agar ultimately comes from one of the [[Dravidian languages|Dravidian]] languages,<ref>{{cite book |last1=Burrow |first1=T. |last2=Emeneau |first2=M. B. |url=https://dsal.uchicago.edu/cgi-bin/app/burrow_query.py?page=4 |title=A Dravidian etymological dictionary |publisher=Oxford University Press |year=1984 |edition=2 |location=Oxfordshire |pages=4 |quote="Ta. akil (in cpds. akiṛ-) eagle-wood, Aquilaria agallocha; the drug agar obtained from the tree; akku eagle-wood. Ma. akil aloe wood, A. agallocha. Ka. agil the balsam tree which yields bdellium, Amyris agallocha; the dark species of Agallochum; fragrance. Tu. agilů a kind of tree; kari agilů Agallochum. / Cf. Skt. aguru-, agaru-; Pali akalu, akaḷu, agaru, agalu, agaḷu; Turner, CDIAL, no. 49. DED 14."}}</ref><ref>{{cite book |last1=Turner |first1=Ralph Lilley |author-link1=Ralph Lilley Turner |url=https://dsal.uchicago.edu/cgi-bin/app/soas_query.py?qs=agaru&searchhws=yes |title=A Comparative Dictionary of the Indo-Aryan Languages |publisher=Oxford University Press |year=1962–66 |location=London |pages=3 |quote="agaru m.n. ʻ fragrant Aloe -- tree and wood, Aquilaria agallocha ʼ lex., aguru -- R. [← Drav. Mayrhofer EWA i 17 with lit.] Pa. agalu --, aggalu -- m., akalu -- m. ʻ a partic. ointment ʼ; Pk. agaru --, agaluya --, agaru(a) -- m.n. ʻ Aloe -- tree and wood ʼ; K. agara -- kāth ʻ sandal -- wood ʼ; S. agaru m. ʻ aloe ʼ, P. N. agar m., A. B. agaru, Or. agarū, H. agar, agur m.; G. agar, agru n. ʻ aloe or sandal -- wood ʼ; M. agar m.n. ʻ aloe ʼ, Si. ayal (agil ← Tam. akil)."}}</ref> probably from Tamil அகில் (akil).<ref>{{cite book |author=Shulman, David |url= |title=Tamil: A biography |publisher=Harvard University Press |year=2016 |pages=19–20 |language=en |chapter= |quote=We have ''ahalim'' [in Hebrew], probably derived directly from Tamil ''akil'' rather than from Sanskrit ''aguru'', itself a loan from the Tamil (Numbers 24.8; Proverbs 7.17; Song of Songs 4.14; Psalms 45.9--the latter two instances with the feminine plural form ''ahalot''. Akil is, we think, native to South India, and it is thus not surprising that the word was borrowed by cultures that imported this plant. |authorlink=David Shulman}}</ref>

===Vernacular names===
[[File:Aquilaria crassna.jpg|thumb|right|Aquilaria tree showing darker agarwood. Poachers had scraped off the bark to allow the tree to become infected by the [[ascomycetous]] mould.]]

Agarwood is known under many names in different cultures:<ref>{{cite book |last=Warrier |first=P. K. |title=Indian Medicinal Plants: A Compendium of 500 Species |volume=1 |publisher=Orient Longman |year=1993 |pages=64–66 |isbn=978-0-86311-464-9}}</ref>
<ref>{{cite book |last=Nadkarni |first=K. M. |title=Indian Materia Medica |volume=1 |publisher=Popular Prakashan |year=2002 |pages=38–39 |isbn=978-8171548194}}</ref>

* Another name is ''Lignum aloes'' or Aloeswood, unrelated to the familiar genus, ''[[Aloe]]''. Also from ''akil'', via Hebrew and Greek.<ref name="Palmer">Palmer, A. Smythe (1882) ''Folk Etymology''</ref>
* In [[Assamese language|Assamese]] it is called ''xasi'' (সাঁচি).<ref name="Panda2009">{{cite book |last=Panda |first=H. |url=https://books.google.com/books?id=SSw_xxrBWFYC&pg=PA182 |title=Aromatic Plants Cultivation, Processing And Uses |date=1 January 2009 |publisher=National Institute of Industrial Re |isbn=978-81-7833-057-0 |page=182 |access-date=8 October 2010}}</ref>
* In [[Bengali language|Bengali]], it is commonly known by the same Sanskrit name as Aguru. The agarwood is known as ''agor gach (আগর গাছ)'' and the agarwood oil as  ''agor ator (আগর আতর)''.
* In [[Odia language|Odia]], it is called ''agara'' (ଅଗର).
* In [[Malayalam language|Malayalam]], it is called ''akil'' (അകിൽ).
* In Cambodia, it is called ''chann crassna''. The fragrance from this wood is called ''khloem chann'' (ខ្លឹមចាន់) or ''khloem chann crassna''. ''khloem'' is 'hard wood' and ''chann crassna'' is the tree species ''Aquilaria crassna'' in the Khmer language.
* In [[Hindustani language|Hindi]] it is known as ''agar'', which is derived originally from the [[Sanskrit]] ''aguru''.<ref>Pusey, Edward Bouverie (1885) ''Daniel the Prophet: Nine Lectures, Delivered in the Divinity School of the University of Oxford'' Funk & Wagnalls, New York, [[iarchive:danielprophetni00pusegoog/page/n518|p. 515]], {{OCLC|5577227}}</ref><ref>[http://vedabase.net/a/aguru "Aguru"] {{webarchive|url=https://web.archive.org/web/20100607130524/http://vedabase.net/a/aguru|date=7 June 2010}} in Sanskrit Dictionary from Bhaktivedanta VedaBase Network</ref>
* In [[Sinhalese language|Sinhala]] Agarwood producing ''[[Gyrinops walla]]'' tree is known as "Walla Patta" (වල්ල පට්ට).
* In [[Tamil language|Tamil]] it is called ''aghi'' (அகில்) though what was referred in ancient Tamil literature could well be ''Excoecaria agallocha''.
* In [[Telugu language|Telugu]] and [[Kannada]], it is known by the same Sanskrit name as ''Aguru''.
* It is known as ''Chénxiāng'' (沉香) in [[Chinese language|Chinese]], ''Chimhyang'' ({{lang|ko|침향}}) in [[Korean language|Korean]], ''Jinkō'' (沈香) in [[Japanese language|Japanese]], and ''trầm hương'' in [[Vietnamese language|Vietnamese]]; all meaning "deep scent" and alluding to its intense scent. In Japan, there are several grades of ''Jinkō'', the highest of which is known as ''Kyara'' (伽羅).<ref>{{Cite book |last=Morita |first=Kiyoko |title=The Book of Incense: Enjoying the Traditional Art of Japanese Scents |publisher=Kodansha USA |year=1999 |isbn=978-4770023896}}</ref> In [[Vietnam]], ancient texts also refer to the use of agarwood in relation to travelling Buddhist monks.<ref>{{cite journal |last1=Persoon |first1=G.A. |title=Agarwood: the life of a wounded tree |journal=IIAS Newsletter |publisher=IIAS, Leiden |volume=45 |issue=2007 |pages=24–25}}</ref>
* In [[Standard Tibetan|Tibetan]] it is known as ཨ་ག་རུ་ (a-ga-ru). There are several varieties used in [[Tibetan Medicine]]: unique eaglewood, yellow eaglewood: ཨ་ག་རུ་སེར་པོ་ (a-ga-ru ser-po), white eaglewood: ཨར་སྐྱ་ (ar-skya), and black eaglewood: ཨར་ནག་(ar-nag).<ref>Parfionovitch, Yuri; Dorje, Gyurme and Meyer, Fernand (1992) ''Tibetan medical paintings: illustrations to the Blue beryl treatise of Sangye Gyamtso (1653–1705)'' (English edition of Tibetan text & paintings) (2 volumes) Serindia, London, {{ISBN|0-906026-26-1}}</ref>\
* Both agarwood and its resin distillate/extracts are known as ''oud'' (عود) in [[Arabic language|Arabic]] (literally "rod/stick") and used to describe agarwood in Arab countries.<ref>Burfield, Tony (2005) [http://www.cropwatch.org/agartrading.htm "Agarwood Trading"] {{webarchive|url=https://web.archive.org/web/20100401082004/http://www.cropwatch.org/agartrading.htm|date=1 April 2010}} ''The Cropwatch Files'', Cropwatch</ref> Western perfumers also often use agarwood essential oil under the name "oud" or "oudh".<ref>Branch, Nathan (30 May 2009) [http://www.nathanbranch.com/2009/05/dawn-spencer-hurwitz-oude-arab.html "Dawn Spencer Hurwitz Oude Arabique (extrait)"] {{Webarchive|url=https://archive.today/20120906064107/http://www.nathanbranch.com/2009/05/dawn-spencer-hurwitz-oude-arab.html|date=6 September 2012}} (fashion and fragrance reviews)</ref>
* In English speaking Europe it was referred to as ''Lignum aquila'' (eagle-wood) or ''Agilawood'', from similarity to Tamil-Malayalam ''aghil''.
* In [[Indonesian language|Indonesian]] and [[Malay language|Malay]], it is called ''gaharu''.
* In The [[Philippines]], it is known as ''Lapnisan''.
* In [[Papua New Guinea]] it is called "ghara" or eagle wood.{{Citation needed|date=September 2010}}
* In [[Thai language|Thai]] it is known as ''mai kritsana'' (ไม้กฤษณา).<ref>[http://ptmk.dtam.moph.go.th/book/%E0%B8%81%E0%B8%A4%E0%B8%A9%E0%B8%93%E0%B8%B2.pdf "สำนักคุ้มครองภูมิปัญญาฯ"] {{Webarchive|url=https://web.archive.org/web/20110825073425/http://ptmk.dtam.moph.go.th/book/%E0%B8%81%E0%B8%A4%E0%B8%A9%E0%B8%93%E0%B8%B2.pdf|date=25 August 2011}}, page 1 (๑), in Thai</ref>
* In [[Laos]] it is known as ''mai ketsana'' (ໄມ້ເກດສະໜາ).<ref>Hkum, Seng Hkum N and Maodee, M. (July 2005) [http://rightslinklao.org/eng/index.php?option=com_docman&task=doc_download&gid=36&Itemid=70 "Marketing and Domestication of NTFPs in North Phonsali Three Districts"] NPADP Presentation, NTFP MIS Workshop Luangprabang, North Phongsali Alternative Development Project, United Nations Office on Drugs and Crime</ref>
* In Myanmar ([[Burmese language|Burmese]]), it is known as ''Thit Mhwae'' (သစ်မွှေး).

== Formation ==

===Production mode===
There are seventeen species in the genus ''[[Aquilaria]]'', large evergreens native to [[southeast Asia]] and [[south asia]], of which nine are known to produce agar wood.<ref name="Ng1">{{cite journal|author =Ng, L.T. |author2=Chang Y.S. |author3=Kadir, A.A. |year=1997|title=A review on agar (gaharu) producing Aquilaria species|journal=Journal of Tropical Forest Products|volume=2|issue=2|pages=272–285}}</ref> Agarwood can in theory be produced from all members, but until recently it was primarily produced from  ''A. malaccensis'' (''A. agallocha'' and ''A. secundaria'' are synonyms for ''A. malaccensis'').<ref name="Broad"/> ''A. crassna'' and ''A. sinensis'' are the other two members of the genus that are commonly harvested. The [[gyrinops]] tree can also produce agarwood.<ref>''The genus Gyrinops, is closely related to Aquilaria and in the past all species were considered to belong to Aquilaria.'' Blanchette, Robert A. (2006) [http://forestpathology.cfans.umn.edu/Papua%20New%20Guinea%20Agarwood%20Research.htm "Cultivated Agarwood – Training programs and Research in Papua New Guinea"], Forest Pathology and Wood Microbiology Research Laboratory, Department of Plant Pathology, University of Minnesota</ref><ref>{{Cite web |title=Cultivated Agarwood - Training programs and Research in Papua New Guinea {{!}} Forest Pathology |url=https://forestpathology.cfans.umn.edu/research-projects/agarwood/papua-new-guinea |access-date=2025-02-07 |website=forestpathology.cfans.umn.edu}}</ref>

[[Image:condensers.jpg|thumb|right|[[Steam distillation]] process used to extract agarwood essential oils]]

Agar wood forms in the trunk and roots of trees that have been penetrated by an [[Ambrosia beetle]] insect feeding on wood and oily resin, ''Dinoplatypus chevrolati''. The tree may then be infected by a mould, and in response it produces a salutary self-defence material to conceal damages or infections. While the unaffected wood of the tree is relatively light in colour, the resin dramatically increases the mass and density of the affected wood, changing its colour from a pale beige to yellow, orange, red, dark brown or black. In natural forests, only about 7 out of 100 Aquilaria trees of the same species are infected and produce aloes/agar wood. A common method in planted forestry is to [[inoculate]] trees with the fungus. It produces a "damage sap" and is referred to as "fake" aloes/agar wood.<ref name="Ng1" /><ref>{{cite journal|journal=Molecules|title=Agarwood—The Fragrant Molecules of a Wounded Tree|volume=27|issue=11|article-number=3386|date=May 2022|last1=Shivanand|first1= Pooja|last2=Arbie|first2=Nurul Fadhila |last3=Krishnamoorthy|first3=Sarayu|last4=Ahmad|first4=Norhayati|pmc=9181942|pmid= 35684324|doi=10.3390/molecules27113386 |doi-access=free }}</ref>

Oud oil can be distilled from agar wood using steam; the total yield of oil for 70&nbsp;kg of wood will not exceed 20 ml.<ref>Harris, 1995</ref><ref>{{Cite web |last=Grover |first=Purva |title=An ode to the oud: The scent of Arabia |url=https://www.khaleejtimes.com/arts-and-culture/an-ode-to-the-oud-the-scent-of-arabia |access-date=2025-02-07 |website=Khaleej Times |language=en}}</ref>

===Composition===
The composition of agarwood oil is exceedingly complex with more than 150 chemical compounds identified.<ref name=chem-rev /> At least 70 of these are [[terpenoids]] which come in the form of [[sesquiterpenes]] and [[chromones]]; no [[monoterpenes]] have been detected at all. Other common classes of compounds include [[agarofuran]]s, [[Cadalene|cadinane]]s, [[eudesmane]]s, [[Valencene|valencane]]s and [[eremophilane]]s, [[Guaiene|guaiane]]s, [[prezizane]]s, [[vetispirane]]s, simple volatile aromatic compounds as well as a range of miscellaneous compounds.<ref name=chem-rev /> The exact balance of these materials will vary depending on the age and species of tree as well as the exact details of the oil extraction process.

==Perfumery==
Oud has become a popular component in perfumery. Most brands have a creation based on or dedicated to "oud" or an accord of oud created through the use of certain chemical scent components. Few perfume houses use real oud in their creations. This is because oud is very expensive and potent. Oud is generally used as a base note and is traditionally paired with rose. Oud essential oil is available on the internet but care should be taken in choosing the vendor. Due to the fact that oud is such an expensive material there is a big market for diluting oud oil with patchouli or other chemical components.

Oud scent is popular in the [[Middle East]], the [[Arab world]], and in [[Arab culture]], where it is used as a traditional aromatic and perfume in many forms. Oud is also one of the reasons why the Arab region developed trade routes in ancient times. Popular amongst [[Muslims]], it has been traditionally used in [[Mosques]] where the incense chips are burned.<ref>{{cite web | url=https://emirateswoman.com/history-and-meaning-of-oud-in-the-middle-east/#:~:text=The%20pure%20extract%20from%20the,sense%20of%20magic%20and%20mystique. | title=The history and meaning of oud in the Middle East | date=11 November 2021 }}</ref>

==''Aquilaria'' species that produce agarwood==
The following species of ''[[Aquilaria]]'' produce agarwood:<ref name="Ng1"/>
* ''[[Aquilaria acuminata]]'', found in Papua New Guinea, Indonesia & Philippines
* ''[[Aquilaria apiculata]]'', found in [[Philippines]]
* ''[[Aquilaria baillonil]]'', found in Cambodia and Thailand 
* ''[[Aquilaria banaensae]]'', found in Vietnam
* ''[[Aquilaria beccariana]]'', found in [[Indonesia]]
* ''[[Aquilaria brachyantha]]'', found in Malaysia
* ''[[Aquilaria crassna]]'' found in [[Cambodia]], [[Malaysia]], Thailand, Laos and [[Vietnam]]
* ''[[Aquilaria cumingiana]]'', found in Indonesia and Malaysia
* ''[[Aquilaria filaria]]'', found in [[New Guinea]], the [[Moluccas]], and [[Mindanao]] (Philippines)<ref>{{GRIN | ''Aquilaria filaria'' | 448936 | access-date = 22 July 2013}}</ref>
* ''[[Aquilaria grandiflora]]'', found in China
* ''[[Aquilaria hirta]]'', found in Thailand, Indonesia and Malaysia<ref>{{GRIN | ''Aquilaria hirta'' | 448917 | access-date = 22 July 2013}}</ref>
* ''[[Aquilaria khasiana]]'', found in Bangladesh and India.
* ''[[Aquilaria malaccensis]]'', found in Indonesia, Malaysia, Laos, Thailand, and India
* ''[[Aquilaria microcarpa]]'', found in Indonesia and Malaysia
* ''[[Aquilaria rostrata]]'', found in Malaysia
* ''[[Aquilaria sinensis]]'', found in China and Laos
* ''[[Aquilaria subintegra]]'', found in [[Cambodia]], [[Thailand]]

<nowiki>*</nowiki> Sri Lankan agarwood is known as [[Walla Patta]] and is of the ''[[Gyrinops walla]]'' species.

==Conservation of agarwood-producing species==
[[Overharvesting]] and [[habitat loss]] threatens some populations of agarwood-producing species.  Concern over the impact of the global demand for agarwood has thus led to the inclusion of the main taxa on [[CITES]] Appendix II, which requires that international trade in agarwood be monitored. Monitoring is conducted by Cambridge-based [[Traffic (conservation programme)|TRAFFIC]] (a joint [[World Wide Fund for Nature|WWF]] and [[International Union for Conservation of Nature|IUCN]] programme).<ref name=":1">{{cite book |last1=Lim |first1=Teckwyn |last2=Awang Anak |first2=Noorainie |title=Wood for the Trees: A review of the agarwood (gaharu) trade in Malaysia |date=2010 |publisher=TRAFFIC Southeast Asia |location=Petaling Jaya |pages=108 |url=https://www.traffic.org/site/assets/files/3179/wood-for-the-trees-agarwood-malaysia.pdf}}</ref> CITES also provides that international trade in agarwood be subject to controls designed to ensure that harvest and exports are not to the detriment of the survival of the species in the wild.<ref>{{Cite book |last1=Thompson |first1=I. D. |url=https://cites-tsp.org/wp-content/uploads/2022/11/Review_of_the_agarwood_producing_genera.pdf |title=Expensive, Exploited and Endangered, A review of the agarwood-producing genera Aquilaria and Gyrinops: CITES considerations, trade patterns, conservation, and management. |last2=Lim |first2=T. |last3=Turjaman |first3=M. |publisher=International Tropical Timber Organization (ITTO) |year=2022 |location=Yokohama, Japan |editor-last2= |editor-first2= |editor-last3= |editor-first3= }}{{Dead link|date=September 2025 |bot=InternetArchiveBot |fix-attempted=yes }}</ref>

In addition, agarwood plantations have been established in a number of countries, and reintroduced into countries such as Malaysia and Sri Lanka as commercial plantation crops.<ref name=":1" /> The success of these plantations depends on the stimulation of agarwood production in the trees.  Numerous inoculation techniques have been developed, with varying degrees of success.<ref name="Ng1" />

== See also ==
* [[Incense in India]]
* [[Sandalwood]]
* [[Agalloch]], the band named after the agarwood

==References==
{{Reflist|30em}}

==Further reading==
{{cite book
|last1=Snelder
|first1=Denyse J.
|last2=Lasco
|first2=Rodel D.
|title=Smallholder Tree Growing for Rural Development and Environmental Services: Lessons from Asia
|url=https://books.google.com/books?id=LmA_5zxDSRkC&pg=PA248
|access-date=8 October 2010
|date=29 September 2008
|publisher=シュプリンガー・ジャパン株式会社
|isbn=978-1-4020-8260-3
|page=248 ff}}

{{cite journal
|last1=Jung
|first1=Dinah
|title=The Cultural Biography of Agarwood—Perfumery in Eastern Asia and the Asian Neighbourhood
|date=1 January 2013
|journal= Journal of the Royal Asiatic Society
|volume=23
|issue=1
|pages=103–125
|url=https://archiv.ub.uni-heidelberg.de/volltextserver/20194/1/DJung-CulturalHistoryBiographyOfAgarwood-Postprint2016.pdf
|access-date=30 October 2016}}

==External links==
* {{Commons category-inline}}
* {{wiktionary-inline}}
* [[Hong Kong Herbarium]] [https://web.archive.org/web/20050813081123/http://www.hkherbarium.net/Herbarium/topics/Aquilaria/Aquilaria_E.htm factsheet of ''Aquilaria sinensis''] (archived 13 August 2005)
* [https://www.balashon.com/2008/03/aloe.html Etymology of agarwood and aloe]
* [https://web.archive.org/web/20130908181916/http://www.cropwatch.org/agarmed.htm The Cropwatch Files: Traditional and Medicinal Uses of Aquilaria / Agarwood]

{{Worship in Hinduism}}

[[Category:Incense material]]
[[Category:Resins]]
[[Category:Types of wood]]
[[Category:Medicinal plants of Asia]]
[[Category:Perfume ingredients]]