Appearance & recognition
Resak is a resinous dipterocarp with narrow, elliptic leaves and small pale flowers in branching clusters. The oblong brown fruits have a different outline from the long-winged fruits of keruing. This variety of reproductive structures is useful when learning forest botany: dipterocarp does not mean that every species produces the same helicopter-like fruit.
Sources & references · 1
National Parks Board Singapore · Vatica rassak — Flora & Fauna WebRange & habitat
Its native range includes Borneo and extends into other parts of Malesia. It belongs to the forest canopy flora rather than to a cultivated fruit crop. Scientific accounts are valuable for separating species-level distribution from broad assumptions about all resak timber. Material use and conservation should therefore start with the accepted name Vatica rassak and the origin of the tree concerned.
Sources & references · 1
National Parks Board Singapore · Vatica rassak — Flora & Fauna WebHow the plant grows
The tree can reach roughly 30–35 metres. Narrow elliptic leaves alternate along the twigs, with conspicuous triangular stipules near young growth. Sticky resin exudes from injured tissue. Pale flowers grow in branching panicles, and oblong fruits are around four centimetres long. The native range continues east of Borneo through the Philippines, Sulawesi and the Moluccas to New Guinea, so this is not a Borneo-only endemic.
