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Casuarina equisetifolia L.

Family Name: Casuarinaceae
Common Name: Casuarina, Common Rhu, Common Ru, Horsetail Tree, Beach She-Oak, Whistling Pine, Aru, Southsea Ironwood, Mile Tree, Australian Pine, Cemara Laut, Horsetail Casuarina, She-oak, Ru, 木麻黄
Full Sun: 6-8h Moderate Water Native to Singapore Herb & Spice Coastal Roadside Tree / Palm Tree

Name

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

Classifications and Characteristics

Plant Division Angiosperms (Flowering Seed Plants) (Monocotyledon)
Plant Growth Form Tree (Big (>30m))
Lifespan (in Singapore) Perennial
Mode of Nutrition Autotrophic
Plant Shape Open
Maximum Height 30 m to 40 m
Maximum Plant Spread / Crown Width 15 m

Biogeography

Native Distribution Throughout Southeast Asia (including Singapore) to Australia and the Pacific Islands.
Native Habitat Terrestrial (Coastal Forest), Shoreline (Backshore, Sandy Beach)
Preferred Climate Zone Tropical, Sub-Tropical / Monsoonal
Local Conservation Status Native to Singapore (Common)

Description and Ethnobotany

Growth Form It is a tree with a rather open canopy, up to 40m tall.
Foliage The true leaves are reduced to tiny scales held in whorls, surrounding grey-green needle-like twigs. This gives rise to the pine-like appearance of the tree.
Flowers Flowers are generally dioicious (male and female flowers on separate plants) although occasionally some trees are monoecious. The male flowers are tiny inconspicuous spikes borne on the ends of green twigs, while the female flowers are small brownish heads on the swollen ends of brownish twigs.
Fruits The fruits are small, flattened winged nuts contained in cone-like clusters which split open when ripe. The Scaly-Breasted Munia (Lonchura punctulata) has been observed to feed on the seeds of this tree, but is probably an exception as very few birds exploit this food source.
Others - Plant Morphology Native to Sinapore, and also naturalised in many parts of the tropics. A hardy, fast-growing, sun-loving pioneer species. Tolerates salt and poor soils, and is found naturally along sandy coasts. Also used as soil-improvers, as roots form nitrogen-fixing associations with soil microbes. Although it resembles a pine tree or conifer in appearance, it is actually an angiosperm (flowering plant) and not related to the non-flowering pine family at all.The crown is distinctly conical in young trees, but becomes more irregular with maturity. It has a delicate, wispy appearance.
Habitat It grows along sandy coasts and coastal forests.
Cultivation It can be propagated by seed.
Etymology Latin Casuarina, meaning Cassowary-like, from the common Malayan name pohon kasuari (cassowary tree), as the the branches resemble the feathers of Cassuarius cassuarius. Latin equisetifolia, with leaves like a horsetail, referring to the reduced leaves of the tree along the branch, which resemble that of Equisetum species.
Ethnobotanical Uses Food (Herb and Spice)
Medicinal ( The bark is used to treat dysentery and diarrhoea. The twigs are used for swelling and as a wash for beri beri.)
Timber & Products ( The wood of this tree is extremely hard and dense, and has been used for construction of stilts, poles and fences in coastal areas. It is also an excellent fuel wood and is among the hottest burning fuel woods in the world. It is also frequently planted as a windbreak and to stabilise coastal sand dunes.)

Landscaping Features

Landscaping It is suitable for parks and gardens on poor infertile soils or along seashores.
Desirable Plant Features Ornamental Form
Plant & Rootzone Preference - Tolerance Saline Soils / Salt Spray, Well-Drained Soils, Poor Infertile Soils
Landscape Uses Coastal, Roadside Tree / Palm, Parks & Gardens, Beachfront / Shoreline

Fauna, Pollination and Dispersal

Pollination Method(s) Abiotic
Seed or Spore Dispersal Abiotic

Plant Care and Propagation

Light Preference Full Sun
Water Preference Moderate Water
Propagation Method Seed

Foliar

Foliage Retention Evergreen
Mature Foliage Colour(s) Green
Foliar Modification Reduced / Needle-like, Scale-like
Foliar Type Simple / Unifoliate
Foliar Arrangement Along Stem Whorled
Foliar Attachment to Stem Sessile
Foliar Shape(s) Non-Palm Foliage
Leaf Area Index (LAI) for Green Plot Ratio 2.5 (Tree - Open Canopy)

Floral (Angiosperm)

Flower & Plant Sexuality 1 Unisexual Flowers
Flower & Plant Sexuality 2 Monoecious
Flower Grouping Cluster / Inflorescence

Fruit, Seed and Spore

Mature Fruit Colour(s) - Angiosperms and Gymnosperms Brown
Fruit Type 1 Indehiscent Dry Fruit
Fruit Type 2 Samara

Image Repository

Images

Others

Master ID 1500
Species ID 2793
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: 20 August 2021.
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