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Alstonia angustiloba


Alstonia angustiloba Miq.

Family Name: Apocynaceae
Synonyms: Alstonia pneumatophora Monach. var. petiolata
Common Name: Common Pulai, Pulai, 黑板树, 橡皮树


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 Tiered
Maximum Height 25 m to 40 m
Maximum Plant Spread / Crown Width 10 m


Native Distribution Sumatra, Peninsular Malaysia, Singapore, Borneo, and Java
Native Habitat Terrestrial (Primary Rainforest, Secondary Rainforest, Freshwater Swamp Forest)
Preferred Climate Zone Tropical
Local Conservation Status Native to Singapore (Least Concern (LC))

Description and Ethnobotany

Growth Form It is a tree up to 40 m tall, with a pagoda-shaped crown, and tiered branching.
Trunk Bark dark grey, smooth when young, becoming slightly cracked when it gets older. The wood is pale yellow and soft.
Foliage Its four- to nine-whorled, stalked leaves have somewhat leathery leaf blades that are oval-shaped, glossy dark green above, pale green below, and 4.5–22 by 2.1–7 cm, with short tips. Its leaf blades also possess numerous secondary veins that are almost perpendicular to the midrib. Milky-white latex is exuded from the broken leaf parts.
Flowers Its fragrant flowers are creamy white, 8.5 mm wide, and develop in clusters of 3–8 at the end of the twigs, on 3–14 cm-long shoots.
Fruits Its fruits develop as a pair of pods that are smooth, 15–35 by 0.2–0.6 cm, covered with brown hairs, and contain many seeds. Its dark brown, wind-dispersed seeds are smooth, oblong, flat, and 5–7 by 1.3–1.5 mm.
Habitat It grows in primary and secondary forests, in swamps, on hills, loam or sandy soils up to 200 m altitude. It is known locally from Western Catchment, Nee Soon, Bukit Mandai, Bukit Timah, Upper Pierce Reservoir, Tampines, Pulau Ubin, Mount Faber, and Lazarus Island.
Associated Fauna It is the preferred local food plant for caterpillars of the moths, Daphnis hypothous, and Parotis marginata. Its flowers are also insect-pollinated.
Cultivation It can be propagated by seed.
Etymology Latin Alstonia, commemorates Dr. Charles Alston (1685–1760), a professor of botany at Edinburgh University; Latin angustiloba means having narrow lobes, referring to the narrow calyx lobes of the flower
Ethnobotanical Uses Medicinal ( Abscesses and boils can be treated using the latex from the bark.)
Timber & Products ( The soft wood is used in making floor boards, household items, matches, and posts.)
Cultural / Religious ( Heritage Tree : There are 11 individuals of Alstonia angustiloba listed as Heritage Trees in Singapore. They are found all over Singapore. To find out more about these trees, please visit the Heritage Tree Register.)

Landscaping Features

Landscaping It is planted along expressways, major roads, and in urban landscapes as an ornamental tree because of its attractive growth form. It is also tolerant of a wide range of soil types from waterlogged to drier conditions.
Desirable Plant Features Fragrant (Flowers) (Day, Night), Ornamental Flowers, Ornamental Foliage, Ornamental Form
Plant & Rootzone Preference - Tolerance Moist Soils, Well-Drained Soils, Fertile Loamy Soils
Landscape Uses General, Roadside Tree / Palm, Parks & Gardens, Small Gardens, Riverine, Shade Providing Tree / Palm
Thematic Landscaping Naturalistic Garden, Fragrant / Aromatherapy Garden

Fauna, Pollination and Dispersal

Fauna Pollination Dispersal Associated Fauna Caterpillar Moth Food Plant (Leaves, Associated with: Parotis marginata)
Pollination Method(s) Biotic (Fauna)
Seed or Spore Dispersal Abiotic

Plant Care and Propagation

Light Preference Full Sun
Water Preference Moderate Water
Plant Growth Rate Moderate
Propagation Method Seed


Foliage Retention Evergreen
Mature Foliage Colour(s) Green
Mature Foliage Texture(s) Smooth, Leathery
Foliar Type Simple / Unifoliate
Foliar Arrangement Along Stem Whorled
Foliar Attachment to Stem Petiolate
Foliar Shape(s) Non-Palm Foliage (Oval)
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
Flower Grouping Cluster / Inflorescence
Flower Location Terminal
Flower Symmetry Radial

Fruit, Seed and Spore

Mature Fruit Colour(s) - Angiosperms and Gymnosperms Brown
Fruit Classification Simple Fruit
Fruit Type 1 Dehiscent Dry Fruit
Fruit Type 2 Follicle

Image Repository



Master ID 1411
Species ID 2704
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: 05 January 2023.