Langkawi’s two main archipelago of 99 islands comprises 477 sq km of land area. Langkawi’s two main terrestrial habitats harbouring biological diversity are inland forests and mangrove forests. The latter comprises one of the richest and most extensive mangrove forest systems in Southeast Asia, with 55 mangrove species, representing nearly half of the world’s total. Here can also be found a species of cycad, Cycas circinalis, which is one of the oldest ‘living fossils’ in the world, dating back to at least the Jurassic, and perhaps as far back as the Triassic.
When both salt and fresh water are present, this tree can grow up to 14m. It has leaves that are glossy green on the upper surface and silvery white on the bottom surface. A seed-bearing plant, the flowers range from white to a golden yellow colour, and bloom in clusters of three to five.
No other species of the Bruguiera family develops leaves as large as the Bruguiera gymnorhiza does. It grows up to 25cm, with a smooth upper side and a waxy bottom. The flowers are distinct, with colours varying from orange, to pink and red. Unlike other members of the Bruguiera family, this specific tree produces fruits. Its timber is used for charcoal, firewood and construction.
When it is blooming, the plant is easily noticed by its distinct, creamy white coloured flowers. The leaves are smooth and spirally arranged. The fruit, spherical in shape, is mainly eaten by birds.
The leaves of this tree have a papery and slightly leathery feel, with white flower clusters forming across the leaves. It has an egg-shaped fruit that contains a single seed.
A small tree, the Cerbera odollam bears a highly toxic fruit that has been used for manufacturing bioinsecticides and deodorants (not to mention more sinister purposes!). The fruit, when still green, looks like a small mango but slowly turns brown when exposed to air. The Cerbera odollam grows in muddy tidal river banks and produces white fragrant flowers.
This multi-stemmed tree develops large buttress roots. Its leaves are long and grow in opposite pairs. It has an egg-shaped fruit that changes colour as it matures. Growing on well-drained soil, the Ceriops tagal is favoured as firewood and timber. The bark, producing shades of purple, brown and black, was commercially used as dye for the batik industry.
The Diospyros pilosanthera is a small tree with slender twigs. It bears flowers and edible berries. Its habitat is forests from sea-level to 1,600m altitude. The wood is often used to make furniture.
Growing up to 15m tall, this tree can be found in tidal swamp forests. It bears fragrant flowers which are commonly found in Thai cuisine, where it is eaten sauteed and used to make sour curry. When pounded and gargled with water, the leaves can treat mouth ulcers.
This bushy tree has a milky latex texture that is very poisonous. Contact with skin will cause irritation and blistering, while contact with eyes will cause temporary blindness. It grows clustered leaves that turn red and yellow when old and bears single-seed fruits that look like small, dark capsules. When the leaves are in contact with water, it will stupefy fish, causing them to float to the surface. The tree is found at higher elevations, where salinity is lower.
This shade tree is traditionally used as medicine in Malaysia, where the roots are used to treat toothache, the leaves to relieve headaches, and the juice from the bark as a liver medicine. As it is both a tropical and subtropical tree, it is generally sold as a house plant. Aside from the forests, this tree can also be found planted in gardens and parks.
This is a crooked, copiously branched, small tree. It grows on sandy shores and has large, prominently-veined leaves. It bears fragrant white flowers that are used to treat hemorrhoids. The leaves are used to make a baby bath. The branches make excellent firewood.
A large tree, the heritiera littoralis produces wing-shaped nuts that are only visible on the underside of its leaves. It bears pink flowers that are rough to the touch. The wood of the tree, valued for being tough and durable, has historically been used to make boats and rice pounders.
Commonly found growing on beaches, by rivers and in mangrove swamps, the Hibiscus tiliaceus has many uses: the roots and shoots, when soaked in water, is said to cool fevers. Fibre from the bark is used to make fishing nets. Tempeh can be fermented when soybeans are pressed into the leaf and stored. The wood of the tree is regarded by many as a high quality furniture wood. It also has a distinct flower: bright yellow with a deep red centre. The flowers deepen to orange and finally pink before falling.
A flowering tree in the pea family, the Intsia bijuga grows up to 50m, with a highly buttressed trunk. It has pink petals and a pear-shaped fruit. The termite-resistant wood makes it a highly valued material for flooring, window frames and corner posts.
The Lumnitzera littorea flowers are bright red and grow in bunches. With only five tiny petals, the flowers produce a lot of nectar, making it a bird-pollinated species. The fruits are small and cork-like, with each containing one seed. The leaves, thick and fleshy, contain nitrogen-fixing bacteria. Due to the hard and durable timber, the Lumnitzera littorea is often sought after for building.
This bushy-crowned tree reaches a maximum height of 27m. Its leaves are hairy when young, with upper surfaces gradually becoming smooth and shiny. Tiny, greenish-white flowers grow in clusters, followed by red or blue berries that turn yellow when ripe. The leaves of this tree are used to cure stomach ache and chest pain.
Rhizophora mucronata seedlings and leaves are part of the diet of crab-eating macaques. The tree also prevents coastal erosion, is used in the construction of buildings, and plays an important role in folk medicine. The fruits are edible and can be extracted to make wine, while the shoots can be consumed as a vegetable. It grows up to 30m, with roots that can elongate to the length of a metre.
The most widely distributed Sonneratia species, this unique tree has large pink flowers that look like pompoms, and roots that are cone-shaped. The leaves are spoon-shaped with a faint tinge of pink at the tip. When ripe, the sour fruits are often eaten by the Malays. The timber is used to build boats and houses.
Widely distributed in the tropics, the Thespesia populnea has bell-shaped yellow flowers with a maroon spot in the middle. The timber is used for articrafts, while the bark is used to make ropes.
Unlike other trees, the Xylocarpus granatum has an orange bark that flakes off in patches of green, resembling camouflaged soldier uniforms. Its roots are ribbon-like and extend away from the trunk. The fruit looks like a brown cannon ball and can weigh up to 3kgs. When ripe, the fruit splits open, releasing seeds that germinate as they float away. The flowers are tiny and grow in clusters of white to pink.