It is common in all Malayan mangroves. According to Hsuan Keng, it
was found in mangroves including Kranji, Serangoon, Pulau Seletar.
It was also known as Carpa obovata. Other Malay names for it include
'Nireh' and 'Nyireh Udang'.
Features: A tree 3-8m tall. Compound leaf comprising 2-4 leaflets
(4.5-17cm long) that are oblong (tip rounded rather than sharp),
thick and leathery. The compound leaves are arranged in a spiral and
wither to an orange red. Bark smooth, reddish, flaking off in
patches, revealing greenish new bark so the overall appearance is
blotchy and resembles the camouflaged uniforms used by soldiers.
Trunk base often enlarged with well-developed buttresses forming
narrow ribbon-like undulations extending away from the trunk.
Flowers tiny white to pinkish in clusters on an inflorescence.
According to Tomlinson, the flower has a "strong but pleasant
scent". Bees are recorded as flower visitors and the shape of the
flower suggests it is pollinated by short-tongued insects. It
appears to bloom seasonally, with X. granatum trees on various
shores in Singapore blooming at the same time.
Fruit globular and large (10-25cm in diameter) like a cannon-ball
or bowling-ball, brown with corky seeds. There are usually 8-10
seeds in a single fruit, although 20 seeds have been recorded. The
fruits develop rapidly, usually only one fruit per inflorescence.
The fruit can finally weigh 2-3kgs! When ripe, the fruit splits open
and/or drops off the tree and shatters, releasing the seeds which
float away. The seeds may start to germinate as they float. 'Granatum'
means 'full of seeds'. The angular seeds fit perfectly inside the
round fruit. But once spilled from the fruit, the seeds are hard to
fit back together. So the tree is sometimes called the 'Puzzle nut'
mangrove or 'Monkey puzzle' tree.
Human uses: According to Burkill, it is produces a timber valued
in making boats, houses and furniture. It is also valued as
firewood. The bark is so popular in tanning and tougening fishing
nets that "in one part of Java, it is rare to find a tree which has
not been peeled." The bark is dark outside and bright red within,
and so thin that a tree yields very little of it. Medicinal uses
include the bark for dysentery, roots in a secret recipe against
cholera, and the seeds for various ailments.