pronounced: FY-kuss op-poh-SEE-tuh
Ficus is the Latin word for fig; opposita is from the Latin oppositus, placed opposite.
This species is native to Queensland and the Northern Territory, and has harsh rough leaves with the feel of sandpaper: hence its common name. The juvenile leaves of this plant are highly variable in shape and size. The mature leaves are opposite, or sometimes alternate, ovate or sometimes cordate, the margins finely toothed, the veins prominent. They are dark green above, paler beneath, 4 – 8 cm by 3 – 5 cm, but sometimes larger, with new growth softly hairy. The bark is dark, rough and deeply fissured.
The sandpaper fig grows as either a shrub or a small tree up to about 8 m high. It may be bushy or straggly, depending on the growing conditions. It drier times it will shed leaves extensively. The figs are about 1 cm in diameter or a little larger, borne singly or in pairs in the leaf axils. As they ripen, their colour changes from green to yellow, then to reddish brown, and finally to black. The fruit is edible and palatable. The skin of the fruit is so thin that it is often broken just by touching it. At full maturity the fruit often drips a clear, sweet nectar, and at this stage it is one of the nicest-eating of bush tuckers, and surprisingly rich in Vitamin C, energy and most minerals, with moderate levels of other nutritional elements. Birds love these figs, and usually find the ripe ones before I do.
The tree serves as a food plant for the caterpillars of the Queensland butterfly Philiris innotatus, the Common or Purple Moonbeam. The larvae feed on the leaves, despite the roughness, and leave tracks on the lower surface of the leaves. The caterpillars are difficult to see when they are resting, as they are the same colour as the under surface of the leaves. The lower-side wings of the adult butterfly are white below, but the males are purple above, and the females blue.
The Sandpaper Fig is dioecious†, and the female trees tend to be smaller than the males.
As well as eating the fruits, Aboriginal people found many other uses for the tree. Of course, they used the leaves as sandpaper for smoothing and polishing wooden objects such as spears, woomeras and boomerangs. Just as today in the hardware shop we will specify the grade of sandpaper we wish to buy, in various degrees of fineness and coarseness, so it is also possible to shop around with the Sandpaper Fig – various neighbouring plants will have different degrees of coarseness in their leaves.
The tree also provided a cure for ringworm: the affected skin would be abraded with a leaf, and the milky latex applied to the affected area. Dry straight stems of the tree were used as fire sticks; this is one of the few plants in the north suitable for this purpose. The inner bark was also used to make string.
The timber is difficult to season, especially when left in log form, when it suffers from extreme shrinkage. Sawn boards seem to do better, if given enough air. Items turned while the timber is green also seem to survive fairly well. The grain pattern and colour enable some very effective pieces to be produced. The timber is quite light, sands very easily, and needs to be sealed before finishing.
The pollinator wasp is a member of the genus Kradibia.
This plant is one of those collected in 1770 by Banks and Solander during the voyage of the Endeavour. It was collected at Cape Grafton.
† This seems to be a recent discovery, made by a James Cook University student. Much work remains to be done, especially on flower structure.
