Aleurites moluccanus aka Kukui

Aleurites moluccanus is an evergreen tree in the spurge family. Its common names include candlenut and kukui. Its native range spans tropical and subtropical Asia to the western Pacific. Early human movement makes its exact origins hard to trace. People spread it widely across tropical lands and Pacific islands. Polynesian settlers brought it to Hawaii, where it became naturalized. Hawaii named it the state tree in 1959.

In gardens, it grows 20–50 feet (6–15.24 metres) tall. Its crown can spread to 40 feet (12.19 metres). Some trees reach 90–98 feet (27–30 metres). The dense crown has an uneven outline and wide branches. Some branches hang down to the ground. The trunk is straight and round. Leaves grow in an alternate pattern along the stems. Young leaves often have three to five lobes. Older leaves tend to be oval or triangular. Star-shaped hairs give the leaves a pale, silvery-green look.

Creamy white flowers grow in clusters at the branch tips. Each cluster holds separate male and female flowers. Bees visit the blooms. Flowers can appear more than once a year. Rounded fruits have tough shells that turn from brown to black. Each fruit holds one or two seeds with hard coats. These oil-rich seeds gave the tree its candlenut name. People have used their oil for lamps, candles, and skin products. The tree also serves as a shade tree or garden specimen.

Grow it in full sun, though it accepts light shade. It needs regular water and soil that drains well. Slightly acid loam with moderate moisture gives the best growth. Deep, fertile soil suits it, but it also tolerates poor soil. Long, humid summers suit this tropical tree. Sources place it in USDA zones 10–12. It can survive brief winter lows near 28°F. Growth is moderate, and routine care needs are low. Serious insect and disease problems are few. Canker and dieback can still occur. It can spread beyond plantings and become naturalized.

People use cooked seeds in small amounts as a spice. Larger amounts may have a laxative effect. Fresh seeds are poisonous and must not be eaten. Sources report cyanide in the seeds and toxins in the leaves. Drying or cooking reduces seed toxins, but toxin levels vary. Missouri Botanical Garden warns that all parts are poisonous when eaten. Traditional medicine uses include bark treatments for wounds and bowel complaints. These uses do not remove the plant's toxicity risks.