Sea poison tree seedling (Barringtonia asiatica)
 
Barringtonia asiatica is a large evergreen tree with a dense, spreading canopy that casts a good shade; it can grow up to 25 metres tall. The bole, which is usually short and poorly formed, can be 100 - 150cm in diameter.
The tree is harvested from the wild for local use as a food, medicine and source of wood. It is often planted for shade along boulevards and avenues by the sea. The plant is classified as 'Least Concern' in the IUCN Red List of Threatened Species (2013).
 
Known Hazards The fruit is toxic. The fresh fruit is used for stupefying fish. The seeds have been ground to a powder then added to slow-moving water where it can stun or kill fish for easy capture, suffocating the fish without affecting the flesh.
Range Around the shores of the Indian and Pacific Oceans from Madagascar, Asia, Australia, Pacific Islands.
 
Cultivation Details:
Barringtonia asiatica is native to the wet tropical, moist topical and wet subtropical climatic zones, in areas with a uniform rainfall pattern and a precipitation of around 1,150 - 4,300mm. This species does not tolerate frost and prefer areas with warm temperatures within the range 20 - 35°c. Prefers a position in full sun or light shade. Grows best in a fertile, humid, well-drained soil, though it tolerates shallow, saline and infertile soils. Found in the wild in coastal coral soils with a pH in the range 5.1 - 8.5. Established plants are fairly drought tolerant, and can also tolerate seasonal inundation of the soil. Plants are very tolerant of saline conditions and salt laden winds. Plants thrive in the wild where their roots dabbling in the brackish waters of lagoons, inlets, estuaries and seasonally flooded coastal regions.
 
Barringtona asiatica is a widespread tree present in coastal areas in much of the Tropics. This species is included in the Global Compendium of Weeds, although at present it has only been listed as invasive for the Dominican Republic. However, considering that this tree has a great dispersal capability and its fruits can remain viable and floating on the sea for many months, the likelihood of reaching and colonizing new coastal areas is high. The plant flowers almost all year round, producing seeds for about 8 months of the year in Fiji. The lightly fragrant flowers open in the evening and tempt pollinating bats with their abundant pollen. Mature trees yield about 500 - 2,000 fruits per year.
Plants are not very tolerant of fire.
The fruit is light and buoyant, allowing it to float in sea water and get carried great distances, thus explaining the trees very wide distribution.
 
Edible Uses
The young fruits are cooked for a long time and then eaten as a vegetable in Indo-China, despite them also being used as a fish poison.
Seed. The oily seed is toxic.
Medicinal A decoction of the leaves is used to treat hernia. The leaves are heated and externally applied for stomach-ache. Fresh leaves are applied topically to bring relief from rheumatism and to treat sores.
 
The fruits are applied externally as a treatment for sores.
The toxic seeds are employed as a vermifuge.
Although toxic, the dried nut is ground, mixed with water and drunk to treat coughs, influenza, sore throat and bronchitis. Used externally, the fresh nut is scraped and applied directly to wounds and sores. It is also applied to a swollen spleen after an attack of malaria.
A decoction of the bark is used to treat constipation and epilepsy. The bark is used externally for treating sores.
In tests, the leaf material of this species was active against some tumours.
 
Other Uses:
The dried fruits are used as floats.
The yellowish to red wood is light, soft and easy to split. It is used for making furniture, carving and turnery.
Propagation Seed - best sown as soon as it is ripe. About 70% of the seed germinates in 36 - 63 days. Cuttings.