Alstonia angustiloba or the Common Pulai is a mid-canopy tree that can grow up to 40 m in height. Native to Singapore, it can also be found naturally distributed across primary or secondary forests and swamp forests of Sumatra, Peninsular Malaysia, Borneo and Java. It buttress roots and deeply fluted, dark grey trunk supports a pagoda-shaped crown. The Common Pulai has simple, glossy, dark green leaves that are oval shaped, arranged in whorls. The tree exudes latex when any part of the plant is damaged. In Singapore, flowering can be triggered by distinctly cool dry weather, and the tree produces many sprays of creamy-white flowers accompanied by a heady fragrance reminiscent of burnt sugar.

The Common Pulai and Indian Pulai (Alstonia scholaris) are commonly found in Singapore’s urban landscapes and these two distinct species are similar looking and can be mistaken for one another. However, they can be differentiated by a few botanical characteristics, such as the colour of the flowers and the presence of stipules (a small, leaf-like part found at the base of the leaf stalk). The Indian Pulai has greenish-yellow flowers and the Common Pulai has creamy-white flowers. The Indian Pulai has a stipule at the base of the leaf stalk while the Common Pulai does not.