Dillenia suffruticosa occurs in Indonesia, Malaysia, Singapore and Brunei. It is cultivated widely in the tropics, including Darwin, and has recently begun to become naturalised in the Northern Territory. It has attractive yellow flowers and bright red bird-attracting fruit; birds distribute the seeds. It is now known commonly as simpoh air, or simpur bini in Brunei, where the flowers are used extensively in traditional art.
It is widely used in countries where it is native. The large leaves are used to wrap food, such as tempe, or formed into shallow cones to carry food, such as rice. Their presence often indicates underground water, and wells are dug near them. The fruit pulp is used as a hair wash, and the leaves are also used to staunch blood flow from bad wounds.
In Brunei, it is illustrated on the dollar note and plays an important ecological role in stabilising white sand accumulations in coastal and riverine areas.
The wasp nest on the leaf is Delta sp. (Vespidae, Eumeninae); from the subfamily that includes Potter-wasps. The nest is built from mud and small hairless caterpillars are placed in each cell, (after being stung by the wasp to paralyse them), the wasp stores this food for future hatchling to feed upon. The nests are built in dry, protected areas and the large leaf of the Shrubby Dillenia provides an excellent habitat.