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Alstonia pneumatophora Backer ex den Berger

Family Name: Apocynaceae
Common Name: Marsh Pulai, Pulai Basong
Full Sun: 6-8h Lots of Water Moderate Water Native to Singapore Tree


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

Classifications and Characteristics

Plant Division Angiosperms (Flowering Seed Plants)
Plant Growth Form Tree


Native Distribution Peninsular Malaysia, Borneo, Singapore, Indonesia (Sumatra, Sulawesi)
Native Habitat Terrestrial (Freshwater Swamp Forest, Riverine)
Preferred Climate Zone Tropical
Local Conservation Status Native to Singapore (Critically Endangered (CR))

Description and Ethnobotany

Growth Form Large tree 25-55m tall, with steep buttresses to 8m high and well developed pnuematophore roots (knee shaped roots)
Trunk Bark smooth or sparsely scaly, grey to yelowish grey
Foliage Leaves spatulate  (spoon shape) or sometimes obovate, 4.3-13 cm x 1.5-4.2 cm, leaf tip rouded, sometimes retuse, arranged in whorls of 4-6 (sometimes in whorls of 3), subcoriaceous (somewhat papery),  glabrous on both sides; upper surface of leaves greyish-green, undersurface brownish to drak reddish brown. Leaves with very short/ without stalks, and without a distinct intrapetiolar stipule at base of leaf stalk. 
Flowers Inflorescence compound, 3-10cm long,  forming 2 bunches of densely clustered flowers. Corolla white, lobes spreading in open flower.
Fruits Follicles are pubescent, 10-20cm in length, with numerous seeds 
Habitat This species occupies swampy areas and can be found on periodically inundated areas along streams, where it grows on sandy or heavy loam. 
Similar The leaf shape is similar to Alstonia spatulata, from which it can be easily distinguished from the species by the presence of pneumatophore roots (after which the species takes its name)
Etymology The species epithet 'Pneumatophora' refers to the pneumatophore (knee like) roots that this species produces
Ethnobotanical Uses Cultural / Religious ( Heritage Trees : There is currently one individual of Alstonia pneumatophora listed as a Heritage Tree in Singapore. It can be found at Singapore Botanic Gardens. To find out more about these trees, please visit the Heritage Tree Register.)

Landscaping Features

Desirable Plant Features Ornamental Trunk, Ornamental Form
Plant & Rootzone Preference - Tolerance Moist Soils, Waterlogged Soils (Drains Site)
Landscape Uses Riverine, Marsh / Bog
Thematic Landscaping Marsh Garden, Bird & Wildlife Garden
Usage Hazard - Cons Large Buttress Roots

Fauna, Pollination and Dispersal

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

Plant Care and Propagation

Light Preference Full Sun
Water Preference Lots of Water, Moderate Water
Propagation Method Seed


Foliage Retention Evergreen
Mature Foliage Colour(s) Green

Floral (Angiosperm)

Flower Colour(s) White
Flower Grouping Cluster / Inflorescence

Image Repository



Master ID 32561
Species ID 6973
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: 31 March 2021.