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Intsia bijuga (Colebr.) Kuntze

Family Name: Fabaceae (Leguminosae)
Synonyms: Afzelia bijuga (Colebr.) A.Gray, Afzelia cambodiensis Hance, Afzelia retusa Kurz, Macrolobium bijugum Colebr.
Common Name: Merbau Ipil, Merbau Ayer, Ipil, Kwila, Kayu Besi
Full Sun: 6-8h Moderate Water Native to Singapore Fruit & Vegetable Coastal Roadside Tree / Palm Ornamental Flowers Tree


Family Name
Genus Epithet
Species Epithet
Name Authority
Name Status (botanical)
Common Names

Classifications and Characteristics

Plant Division Angiosperms (Flowering Seed Plants) (Dicotyledon)
Plant Growth Form Tree (Big (>30m))
Lifespan (in Singapore) Perennial
Mode of Nutrition Autotrophic
Plant Shape Irregular
Maximum Height 50 m


Native Distribution From East Africa through Southern India and Singapore, Southeast Asia to Northern Australia, and Polynesia.
Native Habitat Terrestrial (Primary Rainforest, Secondary Rainforest, Coastal Forest), Shoreline (Mangrove Forest)
Preferred Climate Zone Tropical
Local Conservation Status Native to Singapore (Critically Endangered (CR))

Description and Ethnobotany

Growth Form It is a tree that can grow up to 50 m tall, with up to a 250 cm diameter at breast height for the trunk, and can have buttress roots up to 4 m tall and 2 m wide.
Foliage Its spirally arranged, stalked leaves have 1–3 pairs of thinly leathery leaflets that are oppositely arranged. Each leaflet is broadly oval, egg-shaped or drop-shaped, and 2.5–18 by 1.5–12 cm.
Flowers Its flowers are in flowering shoots (inflorescences) that are up to 17 cm long. Its flowers are bisexual. Its white or pink flower petals are 6–30 by 10–35 mm.
Fruits Its fruits are woody pods that have one cavity and one row of seeds, that are oblong, slightly flat, are brown or black when ripe, and 8.5–28 by 4–7.5 cm. Its seeds are hard-coated, 2–3.5 cm in diameter, and 0.8 cm thick.
Habitat It grows usually in coastal areas, but also in inland forests, up to 600 m altitude. It occurs locally in Lim Chu Kang, Pulau Pawai, Pulau Tekong, Pulau Ubin, and Western Catchment Area.
Associated Fauna Its flowers are probably pollinated by insects.
Cultivation It can be propagated by seed.
Etymology Latin Intsia, derived from the Malayalam name for Acacia intsia; Latin bijuga, two pairs joined, referring to its leaves having two pairs of leaflets sometimes.
Ethnobotanical Uses Edible Plant Parts (Edible Fruits, Edible Seeds)
Food (Fruit & Vegetable : Its fruit seems to be laxative. Its seeds can be eaten.)
[Others]: It is cultivated as an ornamental plant.

Landscaping Features

Landscaping It can be grown along roads, parks or large gardens, or in coastal areas, as it can tolerate their hot, sunny, windy, and frequent salt spray conditions.
Desirable Plant Features Ornamental Flowers
Plant & Rootzone Preference - Tolerance Moist Soils, Well-Drained Soils, Saline Soils / Salt Spray
Landscape Uses Coastal, General, Roadside Tree / Palm, Parks & Gardens, Beachfront / Shoreline

Fauna, Pollination and Dispersal

Pollination Method(s) Biotic (Fauna)
Seed or Spore Dispersal Abiotic

Plant Care and Propagation

Light Preference Full Sun
Water Preference Moderate Water
Propagation Method Seed


Foliage Retention Evergreen
Mature Foliage Colour(s) Green
Mature Foliage Texture(s) Leathery, Thin
Foliar Type Simple / Unifoliate, Compound (Even-Pinnate)
Foliar Arrangement Along Stem Alternate, Spiral
Foliar Attachment to Stem Petiolate
Foliar Shape(s) Non-Palm Foliage
Foliar Venation Pinnate / Net
Foliar Margin Entire
Leaf Area Index (LAI) for Green Plot Ratio 3.0 (Tree - Intermediate Canopy)

Floral (Angiosperm)

Flower & Plant Sexuality 1 Bisexual Flowers
Flower Colour(s) White, Green, Pink, Purple
Flower Grouping Cluster / Inflorescence
Flower Location Axillary
Flower Symmetry Bilateral

Fruit, Seed and Spore

Mature Fruit Colour(s) - Angiosperms and Gymnosperms Black, Brown
Fruit Classification Simple Fruit
Fruit Type 1 Dehiscent Dry Fruit
Fruit Type 2 Legume / Pod

Image Repository



Master ID 1678
Species ID 2971
Flora Disclaimer The information in this website has been compiled from reliable sources, such as reference works on medicinal plants. It is not a substitute for medical advice or treatment and NParks does not purport to provide any medical advice. Readers should always consult his/her physician before using or consuming a plant for medicinal purposes.
Species record last updated on: 26 August 2021.

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