pronounced: stur-KEW-lee-uh kwad-RIFF-ih-duh
Sterculia is from the Latin Sterculius, the name of the Roman god who presides over manuring, and quadrifida from quadrifidus, split into four parts, presumably referring to the fruits, although the ones I have seen more often split into two parts.
This medium-sized tree occurs naturally mostly in littoral and riverine rainforest from northern New South Wales to northern Australia and Papua New Guinea. It is quite a rare sub-canopy tree. There are several on Magnetic Island: the one photographed is in the clump of trees by the Sewerage Treatment Plant on the West Point road. I have seen another in Nelly Bay, and there is one by the walkway between Nelly and Geoffrey Bays.
The Peanut Tree is semi-deciduous in the tropics, and deciduous in cooler climates. The bark is a light silvery grey, usually smooth, on a mature tree less than 2.5 cm thick. The bole is cylindrical and usually straight, with no buttresses.
The leaves are simple, alternate but often in pseudo-whorls, ovate or cordate, 5 – 12 cm long, 4 – 8 cm wide. They are either spaced along the branches or clustered at the ends. They are shiny bright green on both sides and have long petioles, up to 7 cm, swollen at both ends. The young leaves and stalks are often hairy. The venation is pinnate, the secondary veins open and prominent, with intramarginal veins absent.
This monoecious tree bears clusters of inconspicuous lemon-scented, creamy white, bell-shaped unisexual flowers from about November to January. The calyx is 5 – 10 cm long, and cream. The female flowers develop into clusters of large (up to 8 cm long) green, leathery, boat-shaped pods that turn bright orange-red as they ripen. When they split open, the interior of the pod is orange, and contains between 2 and 10 large shiny black seeds. These seeds can be eaten, either raw or roasted, and taste like peanuts (hence the common name of the tree). The seed coat should be removed first – notice in the photograph how attractive it is to seed bugs (Physopelta sp.) – and it is not wise to eat too many at once. The remains of old fruits can often be found on the ground under the tree.
The bark is used by Aborigines in their traditional weaving technique to make baskets and nets, and parts of the tree to treat wounds and stings.
The larvae of the moth Tonica effractella feed on the tree.
