Intsia bijuga

{{Short description|Species of tree in the legume family}} {{Redirect-distinguish2|Ipil tree|the Ipil-ipil tree}} {{Use dmy dates|date=October 2024}} {{Speciesbox |image = Intsia bijuga.jpg |status = NT |status_system = IUCN3.1 |status_ref = {{R|IUCN}} |genus = Intsia |species = bijuga |authority = (Colebr.) Kuntze{{R|POWO}} |synonyms = {{Hidden begin|border=0|title=23 synonyms}} {{Tree list}} *for '''''I. bijuga'''''{{R|POWO}} **''Afzelia bijuga'' {{small|(Colebr.) A.Gray}} **''Macrolobium bijugum'' {{small|Colebr.}} **''Outea bijuga'' {{small|(Colebr.) DC.}} *for '''var. ''bijuga'''''{{R|POWO2}} **''Afzelia bijuga'' f. ''sambiranensis'' {{small|R.Vig.}} **''Afzelia madagascariensis'' {{small|(DC.) Baill.}} **''Afzelia tashiroi'' {{small|Hayata}} **''Eperua decandra'' {{small|Blanco}} **''Intsia amboinensis'' {{small|DC.}} **''Intsia cuanzensis'' {{small|Kuntze}} **''Intsia madagascariensis'' {{small|DC.}} **''Intsia moelebei'' {{small|Vieill.}} **''Intsia tashiroi'' {{small|Hayata}} **''Jonesia monopetala'' {{small|Hassk.}} **''Jonesia scandens'' {{small|Roxb.}} **''Jonesia triandra'' {{small|Roxb.}} **''Macrolobium amboinense'' {{small|Teijsm. ex Hassk.}} **''Pahudia hasskarliana'' {{small|Miq.}} **''Phanera scandens'' {{small|(Roxb.) Teijsm. & Binn.}} **''Saraca triandra'' {{small|(Roxb.) Baker}} **''Tamarindus intsia'' {{small|Spreng.}} **''Seymeria madagascariensis'' {{small|Kuntze}} *for '''var. ''retusa'''''{{R|POWO3}} **''Afzelia retusa'' {{small|Kurz}} **''Intsia retusa'' {{small|(Kurz) Kuntze}} {{Tree list/end}} {{Hidden end}} }}

'''''Intsia bijuga''''', commonly known as '''Borneo teak''', '''ipil''', '''merbau''', '''Johnstone River teak''', and '''kwila''', amongst many other names, is a species of tree in the flowering plant family Fabaceae, native to coastal areas from east Africa, through India and Southeast Asia to Australia and the western Pacific. It has significant importance to indigenous cultures in many parts of its range, but is also threatened by illegal logging due to its high quality timber. It is most commonly found in tropical coastal forests.

==Description== ''Intsia bijuga'' is an evergreen tree that usually grows to about {{cvt|25|-|35|m}} tall but may reach {{cvt|50|m}}, a trunk diameter between {{cvt|60|and|125|cm}}, and buttresses up to {{cvt|4|m}} tall and {{cvt|2|m}} wide. The compound leaves are arranged spirally on the twigs, and usually have four broadly oval-shaped and asymmetrical leaflets, each measuring up to {{cvt|18|cm}} long by {{cvt|12|cm}} wide.{{R|RFK|FOA|AFO|NPSING|PNGTREES}}

The inflorescences are terminal and carry many bisexual flowers (i.e. flowers that have both male and female parts). Only one petal is fully developed and is up to {{cvt|3|cm}} long; it is initially white and turns pink or red with age. The fruit is a rather flat woody pod measuring between {{cvt|10|-|28|cm}} long and {{cvt|4|-|8|cm}} broad, with up to 8 disc-shaped seeds about {{cvt|3|cm}} diameter and {{cvt|1|cm}} thick.{{R|RFK|FOA|AFO|NPSING|PNGTREES}}

===Phenology=== In Australia, flowering occurs from December to May.{{R|FOA}}

==Taxonomy== The species was first described as ''Macrolobium bijugum'' by English botanist Henry Thomas Colebrooke in 1819, and was transferred to the genus ''Intsia'' by German botanist Carl Ernst Otto Kuntze in 1891.{{R|IPNI}}

===Infraspecies=== Two varieties are recognised, ''I. bijuga'' var. ''bijuga'' and ''I. bijuga'' var. ''retusa''{{R|POWO}}

===Etymology=== The derivation of the genus name ''Intsia'' is uncertain,{{R|FOA2|TFL}} but it has been suggested it may come from the Malayalam name for ''Acacia intsia''.{{R|NPSING}} The species epithet ''bijuga'' is from the Latin words ''bi'' (two) and ''jugus'' (paired), and is a reference to the two pairs of leaflets in the compound leaf.{{R|FOA}}

===Vernacular names=== Due to the wide distribution of this species, spanning many different language and cultural areas, many common names exist. They include Borneo teak, intsia, Johnstone River teak, Moluccan ironwood, Pacific teak, scrub mahogany and teak in English; and natora, bendora, ifit, ipil, kayu besi, kwila, melila, merbau asam, merbau ayer, merbau ipil, tashiro-mame, and vesi in other languages across its range.{{R|NPSING|FOA|GRIN|BQ}}

==Distribution and habitat== The natural range of ''Intsia bijuga'' is, in broad terms, the Indo-Pacific region. It is native to Tanzania in Africa; the Chagos Archipelago, Madagascar, Mauritius and the Seychelles in the western Indian Ocean; Bangladesh, India and Sri Lanka in the Indian subcontinent; Andaman Islands, Cambodia, Myanmar, Nicobar Islands, Thailand and Vietnam in Indo-China; Taiwan in the South China Sea; Borneo, Java, Malaysia, Maluku, the Philippines, Sulawesi and Sumatra in Malesia; the Bismarck Archipelago, New Guinea and the Solomon Islands in Papuasia; the Northern Territory and Queensland in Australia; and the Caroline Islands, Fiji, the Marianas, the Marshall Islands, New Caledonia, Palau, Samoa, Santa Cruz Islands, Tonga and Vanuatu in the western Pacific Ocean.{{R|POWO|RFK|NPSING|GRIN}}

The species is mostly coastal and inhabits beach forest and the upper reaches of mangrove forest, but it can also be found in rainforest and may even occur up to {{cvt|600|m}} altitude.{{R|RFK|NPSING|FOA}}

==Uses== thumb|Carving from kwila timber The timber of this species is often used due to its durablity and termite resistance compared to other types of wood, making it suitable in engineering and construction contexts as well as decorative work.{{R|RFK|AFO|BQ|GUAMPEDIA}} It has a density of {{cvt|830|kg/m3}} and an above-ground life expectancy of more than 40 years.{{R|BQ}}

The tree had many uses in the indigenous communities where the tree is found—the timber was used for house building and for the construction of canoes and rafts, and for the carving of ornaments and tools. A dye can be extracted from the wood, and an insect repellent can be made from the seeds. Decoctions from various parts of the tree have been used to treat a range of ailments such as diarrhoea, rheumatism, pain, colds and influenza.{{R|FOA|AFO|TFL}}

==Conservation== {{As of|2024|10}}, ''Intsia bijuga'' was classified on a worldwide scale as near threatened by the International Union for Conservation of Nature (IUCN);{{R|IUCN}} however, various regional authorities have given it different ratings. For example, in Queensland, Australia, it has been given least concern status, whereas in the neighbouring Northern Territory it is listed as critically endangered.{{R|DESQLD|FLORANT}} It is also listed as critically endangered in Singapore, but as vulnerable in India.{{R|RBSING|BSI}}

===Illegal logging=== thumb|Felled kwila logs in New Guinea It is believed that the species now exists in large numbers only on the island of New Guinea, and that illegal logging is being carried out there as well as in Indonesia and Malaysia. In 2007, Greenpeace accused China of importing large amounts of illegally-felled ipil logs from New Guinea, and claimed at the time that at the current rate of logging "the species will be virtually wiped out in the next 35 years".{{R|BBC|GREENPEACE|THEGUARDIAN}}

Greenpeace has targeted users in Western countries in order to halt the trade in ipil. In New Zealand, attempts have been made to stop it from being imported. In 2008, retailers were divided as to whether the sale of the timber should be banned. Jim Anderton, who was the Minister in charge of the Ministry of Agriculture and Forestry at that time, did not support a ban and instead left it up to consumer choice.{{R|NZHERALD}}

{{As of|2022}}, illegal harvesting of the trees was still going on in New Guinea.{{R|THEGUARDIAN}}

==Culture== ''Intsia bijuga'' is the official tree of the United States territory of Guam and is a culturally important tree throughout the rest of the Marianas.{{R|GUAMPEDIA}} The ''Tivia'' clan of Suburam village on the north coast of Papua New Guinea believes that the timber has spiritual powers,{{R|THEGUARDIAN}} and the tree is sacred to Fijian people.{{R|TFL|AFO}}

==Gallery== {{gallery |mode=packed |height=170 |File:Intsia bijuga 402449624.jpg|Trunk with buttresses |File:Even pinnate leaflets of Intsia bijuga.jpg|Foliage |File:Intsia-bijuga-SF24199-14.jpg|Flowers |File:Intsia bijuga 258174434.jpg|Mature fruit |File:Intsia-bijuga-SF22162-04.jpg|Seeds }}

==References== {{Reflist|28em|refs= <ref name="IUCN">{{cite iucn |author=Barstow, M. |date=2020 |title=''Intsia bijuga'' |volume=2020 |article-number=e.T32310A2813445 |doi=10.2305/IUCN.UK.2020-3.RLTS.T32310A2813445.en |access-date=15 October 2024}}</ref>

<ref name="POWO">{{cite web |url=https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:500954-1 |title=''Intsia bijuga'' (Colebr.) Kuntze |website=Plants of the World Online |publisher=Royal Botanic Gardens, Kew |year=2024 |access-date=15 October 2024}}</ref>

<ref name="POWO2">{{cite web |url=https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:77173006-1 |title=''Intsia bijuga'' var. ''bijuga'' |website=Plants of the World Online |publisher=Royal Botanic Gardens, Kew |year=2024 |access-date=15 October 2024}}</ref>

<ref name="POWO3">{{cite web |url=https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:967435-1 |title=''Intsia bijuga'' var. ''retusa'' (Kurz) Sanjappa |website=Plants of the World Online |publisher=Royal Botanic Gardens, Kew |year=2024 |access-date=15 October 2024}}</ref><!--

<ref name="WS">{{cite web |url=http://www.wildsingapore.com/chekjawa/text/f106.htm |website=Wild Singapore |title=Ipil - ''Intsia bijuga'' - Family Leguminosae |archive-date=18 May 2006 |archive-url=https://web.archive.org/web/20060518052424/http://www.wildsingapore.com/chekjawa/text/f106.htm }}</ref> -->

<ref name="RFK">{{cite web |url=https://apps.lucidcentral.org/rainforest/text/entities/intsia_bijuga.htm |title=Intsia bijuga |author=F.A. Zich |author2=B.P.M Hyland |author3=T. Whiffen |author4=R.A. Kerrigan |website=Australian Tropical Rainforest Plants, Edition 8 |year=2020 |publisher=Commonwealth Scientific and Industrial Research Organisation |access-date=15 October 2024}}</ref>

<ref name="AFO">{{cite web |title=Intsia bijuga (vesi) |url=http://www.agroforestry.net/tti/Intsia-vesi.pdf |website=Agroforestry |publisher=Agroforestry Net, Inc |access-date=7 April 2021}}</ref>

<ref name="PNGTREES">{{Cite web |title=PNGTreesKey - Intsia bijuga Kuntze|url=https://www.pngplants.org/PNGtrees/TreeDescriptions/Intsia_bijuga_Kuntze.html |access-date=15 October 2024 |website=www.pngplants.org}}</ref>

<ref name="NPSING">{{cite web |title=''Intsia bijuga'' (Colebr.) Kuntze |url=https://www.nparks.gov.sg/florafaunaweb/flora/2/9/2971 |website=Flora and Fauna Web |publisher=Singapore Government |access-date=15 October 2024 }}</ref>

<ref name="IPNI">{{cite web |url=https://www.ipni.org/n/500954-1 |title=''Intsia bijuga'' |website=International Plant Names Index (IPNI) |publisher=Royal Botanic Gardens, Kew |year=2024 |access-date=15 October 2024}}</ref>

<ref name="FOA">{{cite web |url=https://profiles.ala.org.au/opus/foa/profile/Intsia%20bijuga |title=''Intsia bijuga'' |last1=Ross |first1=J.H. |last2=Kodela |first2=P.G. |year=2022 |editor-last=Kodela |editor-first=P.G. |website=Flora of Australia |publisher=Australian Biological Resources Study, Department of Climate Change, Energy, the Environment and Water: Canberra |access-date=15 October 2024}}</ref>

<ref name="FOA2">{{cite web |url=https://profiles.ala.org.au/opus/foa/profile/Intsia |title=''Intsia'' |last1=Ross |first1=J.H. |year=2022 |website=Flora of Australia |publisher=Australian Biological Resources Study, Department of Climate Change, Energy, the Environment and Water: Canberra |access-date=15 October 2024}}</ref>

<ref name="GRIN">{{GRIN |access-date=15 October 2024}}</ref>

<ref name="BQ">{{cite web |title=Wood properties and uses of Australian timbers - Kwila |url=https://www.business.qld.gov.au/industries/farms-fishing-forestry/forests-wood/properties-timbers/kwila |website=Business Queensland |date=12 December 2018 |publisher=Queensland Government |access-date=15 October 2024}}</ref>

<ref name="DESQLD">{{cite web |url=https://apps.des.qld.gov.au/species-search/details/?id=15302 |title=Species profile—''Intsia bijuga'' |year=2024 |website=Queensland Department of Environment and Science |publisher=Queensland Government |access-date=16 October 2024}}</ref>

<ref name="FLORANT">{{cite web |url=https://eflora.nt.gov.au/factsheet?id=952 |title=''Intsia bijuga'' |vauthors= Cowie I, Lewis D, etal |year=2013 |website=FloraNT, Northern Territory Herbarium |publisher=Northern Territory Government, Darwin. |access-date=16 October 2024}}</ref>

<ref name="RBSING">{{cite web |title=Flora (Red Data Book List) |url=https://www.nparks.gov.sg/biodiversity/wildlife-in-singapore/species-list/flora |website=Flora and Fauna Web |publisher=Singapore Government |access-date=15 October 2024}}</ref>

<ref name="BSI">{{cite web |title=Threatened Taxa |url=https://bsi.gov.in/page/en/threatened-taxa |website=Botanical Survey of India |publisher=Government of India |access-date=15 October 2024 |format=PDF}}</ref>

<ref name="BBC">{{cite news |last=Bristow |first=Michael |title=China trade threatens tropical trees |url=https://news.bbc.co.uk/2/hi/asia-pacific/6277518.stm |access-date=16 October 2024 |work=BBC |date=6 July 2007}}</ref>

<ref name="GUAMPEDIA">{{cite web |last1=Wescom |first1=Robert W. |date=2024 |title=Guam Trees: Ifit |url=https://www.guampedia.com/guam-trees-ifit/ |website=Guampedia |access-date=16 October 2024 }}</ref>

<ref name="THEGUARDIAN">{{cite news |last1=Chandler |first1=Jo |title=Fighting off the bulldozers in the sacred kwila forests of Papua New Guinea |url=https://www.theguardian.com/world/2022/oct/09/fighting-off-the-bulldozers-in-the-sacred-kwila-forests-of-papua-new-guinea |access-date=16 October 2024 |work=The Guardian |date=8 October 2022}}</ref>

<ref name="TFL">{{cite book |last1=Thomson |first1=Lex |last2=Thaman |first2=Randolf R. |last3=Martel |first3=François |last4=Elevitch |first4=Craig |editor1-last=Thomson |editor1-first=L. |editor2-last=Doran |editor2-first=J. |editor3-last=Clarke |editor3-first=B. |title=Trees for life in Oceania: conservation and utilisation of genetic diversity |date=2018 |publisher=Centre for International Agricultural Research |location=Canberra |pages=143–146 |url=https://www.aciar.gov.au/sites/default/files/mn201_trees_for_life_-_final_artwork_-_15052018_web_upload_version.pdf |issn=1447-090X |isbn=978-1-925746-18-1 |access-date=17 October 2024}}</ref>

<ref name="GREENPEACE">{{cite web |last1=Stark |first1=Tamara |last2=Cheung |first2=Sze Pang |title=Sharing the Blame - Global Consumption and China's Role in Ancient Forest Destruction |url=https://archivo-es.greenpeace.org/espana/Global/espana/report/other/sharing-the-blame.pdf |website=Greenpeace |publisher=Greenpeace International and Greenpeace China |access-date=16 October 2024 }}</ref>

<ref name="NZHERALD">{{cite news|url=http://www.nzherald.co.nz/environment/news/article.cfm?c_id=39&objectid=10527536|title=Stores divided over calls to ban kwila|last=Gibson|first=Eloise|date=18 August 2008|work=New Zealand Herald|access-date=26 June 2010}}</ref>

}}

==Further reading== * {{cite web|url=http://www.greenpeace.org/international/Global/international/planet-2/report/2008/7/merbau-report-2.pdf|title=Merbau's Last Stand|author1=Sze Pang Cheung |author2=Tiy Chung |author3=Tamara Stark |date=17 April 2007|publisher=Greenpeace International, Amsterdam}} * {{cite book|last=Sihite|first=Jamartin|title=Bintuni Bay Nature Reserve Management Plan - Irian Jaya Barat Province 2006-2030|url=http://www.coral-triangle.org/downloads/Bintuni_english_screen.pdf|date=August 2005|publisher=The Nature Conservancy|isbn=978-979-97700-3-5|access-date=2007-03-22|archive-url=https://web.archive.org/web/20110930192604/http://www.coral-triangle.org/downloads/Bintuni_english_screen.pdf|archive-date=2011-09-30}}

==External links== {{Commonscat}} {{Wikispecies}} *[https://www.gbif.org/species/2963211 See a map] of recorded occurrences of this species at the GBIF website *[https://www.inaturalist.org/observations?iconic_taxa=Plantae&taxon_id=343875&place_id=any See observations] of this species on iNaturalist *[https://flickriver.com/search/Intsia+bijuga/ View images] of this species on Flickriver.com *[https://web.archive.org/web/20070927143858/http://anasia.info/en/img/CIRAD-Merbau.pdf CIRAD Forestry Department — timber data]

bijuga Category:Trees of Africa Category:Flora of tropical Asia Category:Trees of the Pacific Category:Trees of Madagascar Category:Trees of Seychelles Category:Trees of Taiwan Category:Flora of the Zanzibar Archipelago Category:Fabales of Australia Category:Trees of Australia Category:Flora of Queensland Category:Plants described in 1891 Category:Austronesian agriculture