Which tree species is known as the cannonball tree?

Which tree species is known as the cannonball tree? The answer is Couroupita guianensis.

Couroupita guianensis is a tropical tree in the Brazil-nut family, Lecythidaceae. It earned the name “cannonball tree” from its large, spherical, woody fruits, which can reach roughly 20 cm across and hang directly from the trunk and major branches. The fruits may take a year or longer to mature.

The tree is native to lowland rainforests of Central and South America, but it is cultivated in tropical gardens worldwide. Its striking flowers are strongly scented and grow in long clusters on the trunk, an unusual flowering habit called cauliflory. Bees visit the pollen-rich flowers even though they do not produce nectar.

The species is sometimes confused with the sacred sal tree, Shorea robusta, in South and Southeast Asia. That confusion has cultural roots: cannonball trees were introduced to Sri Lanka by the British in 1881 and later planted at Hindu and Buddhist religious sites. The fruit is technically edible, but its odor makes it unpopular with many people.