Simpoh Air Dillenia/Wormia suffruticosa Shrubby Simpoh This distinctive shrubby tree grows vigorously on eroded soil, wasteland, forest edges and swampy areas. Everything about it is large. It has large leaves, and large yellow flowers. The flowers open at 3 am and last only a day. They are pollinated by bees which collect its pollen (the flowers don't produce nectar or a scent) or by small beetles and flies that scramble over it. Almost every flower sets fruit.

Mangrove and wetland wildlife at Sungei Buloh Nature Park Main features: Large shrub or small tree. Grows up to 5m. Leaves: Large (35cm long) oval leaves that are cabbage-like with slightly toothed edges. Flowers: Large yellow, five petals. Fruits: Red, splits open into segments; seeds covered with red flesh. Status in Singapore: Common, particularly on wasteland. World distribution: Throughout West Malesia. Classification: Family Dilleniaceae.

The unopened fruits are surrounded by thick red sepals. To distinguish them from flower buds, the fruits face upwards while flower buds face down. The ripe fruit splits open also at 3 am, into pinkish star-shaped segments to reveal seeds covered in red arils. The plant blooms from age 3-4 and can live for 50-100 years! Plants in the Simpoh family (Dilleniaceae) hiss when the trunk or a branch is cut (you have to put your ear to the cut to hear it). The sound comes from the air that is sucked into the cut vessels.

Uses: The large leaves of the Simpoh Air were used to wrap food such as tempeh (fermented soyabean cakes), or formed into shallow cones to contain traditional "fast food" such as rojak.

The Simpoh Air sends out very deep tap roots to reach underground water sources. So much so that their presence suggests an underground water source, and some people use the plant as a guide to decide where to dig a well. The timber is not useful because it is twisted and very hard.

Traditional medicinal uses: Simpoh Air is used to staunch bleeding wounds, and the fruit pulp may be used to wash the hair (Brunei).

Role in the habitat: The Simpoh Air provides food and shelter for other plants and creatures. It is among the few plants that can germinate and grow on white sands. As a pioneer species, it provides shade for other less hardy plants to establish themselves. The tiny bit red flesh (arils) surrounding the seeds are irresistible to birds, which quickly disperse the seeds. Tailorbirds often make their nests out of the large leaves of the Simpoh Air.

• Bunga Simpor by Dr.s Idris M. Said as background information on the flower which is the logo of the APEC 2000 Summit held in Brunei Darussalam: lots of info on distribution, traditional uses, role in the habitat.
• Tropical Flowers of the Singapore Botanic Garden by James Teiw: brief facts, photos.
• Guide to the Wildflowers of Singapore, online version on the Singapore Science Centre: fact sheet, drawings, photos.

• Ivan Polunin, "Plants and Flowers of Singapore", Times Editions, 1987 (p. 99: description, habitat, distribution, photo).
• Foo Tok Shiew, "A Guide to the Wildflowers of Singapore", Singapore Science Centre, 1985 (p. 24: description, habitat, photo).
• E. J. H. Corner, "Wayside Trees of Malaya: Vol I", Malayan Nature Society, 4th ed., 1997 (p. 232-233: description, habit).

By Ria Tan, 2001