Dungun, The Looking-glass Mangrove

Heritiera littoralis ( Dungun ) (Photo credit: Tatters:))

Names

     There are several different ways to spell the name of this tree. The spelling “dungun” occurs on several internet websites. My Tagalog dictionary spells it “dungon,” and I saw yet another spelling when I visited an archeological site in Butuan.

     Its common name in India is sundari. I am pretty certain that this name is derived from the Sanskrit word “sundara,” which means “beautiful.” The tree is common in the

Sundarbans, a mangrove forest in Bangladesh and in adjacent areas of India.

     In English, it is commonly called the looking glass tree or looking glass mangrove. I have no inside information on how it got these names, but I suspect that the silvery white lower surface of its leaves might have something to do with it. At least, I do not see anything else on the plant that might look like a mirror.

     It is easy to understand why it is called a mangrove, even though it does not tolerate an excessive amount of salt. According to Australian Tropical Rainforest Plants, it grows on the edge of mangrove forests, so people would probably lump them together with the mangroves. And why not? After all, the black mangrove, the red mangrove, and the white mangrove all belong to different families, so there is no reason why another unrelated species should not receive the same common name, especially since it grows in close proximity to the other mangroves.

     Its scientific name is Heritiera littoralis. Some place this species in the botanical family Sterculiaceae, others in Malvaceae.

Range

     Heritiera littoralis grows in Australia, in Africa and Asia not far from the shores of the Indian Ocean, and in some Pacific islands, according to Australian Tropical Rainforest Plants.

Heritiera littoralis Plate from book (Photo credit: Wikipedia)

Vegetation

     At the base of the dungun trunk, the woody tissue projects outward at various points to form projecting arms that lie on the ground and buttress the trunk. These structures are called plank buttresses, plank roots, or buttress roots.

    Dungun has simple leaves with pinnate venation. They grow to a length of four to eight inches. They are two-toned: dark green above and silvery white below. The silvery appearance is due to the scales on the bottom side of the leaf.

Flowers

     According to the Tide Chaser, male and female flowers grow on separate trees. The inflorescence contains a lot of tiny flowers. The flowers have no petals, and their pink or yellow sepals are fused into a cup-shaped or bell-shaped structure with a few pointed lobes symmetrically arranged along the top edge of the cup.

Fruit

     According to Wild Singapore, dungun has massive woody fruit with a flange on one side that resembles the keel of a boat. The same website adds that the fruit can float for weeks. When stranded, the fruit may germinate as the tide begins to ebb.

Uses

     Dungun has a sturdy wood often used in construction. Boats found at the archeological site of Butuan used dungun in their construction. In Malaysia, people used it in such structures as stockades to protect themselves against bullets, according to Wild Singapore.

     The same website testifies that dungun seeds were used to treat dysentery. Their twigs were used as toothbrushes in Malaysia.

References:

Wikipedia: Heritiera littoralis

http://en.wikipedia.org/wiki/Heritiera_littoralis

“A Field Guide to Kenyan Mangroves”: Heritiera littoralis Dryand.

http://www.madeinnys.com/mangrove/h_littoralis.htm

National University of Singapore: Dungun

http://mangrove.nus.edu.sg/guidebooks/text/1062.htm

Wild Singapore: Dungun

http://www.wildsingapore.com/wildfacts/plants/mangrove/heritiera/heritiera.htm

Flowers of India: Looking Glass Mangrove

http://www.flowersofindia.net/catalog/slides/Looking%20Glass%20Mangrove.html

The Tide Chaser: Dungun (Heritiera littoralis)

http://tidechaser.blogspot.com/2011/11/dungun-heritiera-littoralis.html

Australian Tropical Rainforest Plants: Heritiera littoralis

http://keys.trin.org.au/key-server/data/0e0f0504-0103-430d-8004-060d07080d04/media/Html/taxon/Heritiera_littoralis.htm