I am disappointed in the fact that many people seem to regard the Sandpaper Fig as a bit of a weed. In a well designed garden which attracts lots of birds, the Sandpaper Fig will often appear. It doesn't take an expert botanist to identify a Sandpaper Fig. In fact, most people can do it blindfolded, due to the rough coarseness of the leaves. The leaves do vary considerably in shape, from a pretty standard sort of broadly lanceolate shape to a sharply pointed thin leaf with long lobes at the base. Botany student, Dale Dixon, is currently examining Sandpaper Figs at James Cook University and will hopefully be able to shed light on why the leaf shape varies so much at some stage in the future.
I was always at a loss to explain why some Sandpaper Figs grew into large, shady trees while others remained small shrubs, until Dale found that Sandpaper Figs were not bisexual like many of their close relatives, but had male and female on different trees. Since then I have made some closer observations and found the following:
Very large trees never seem to set ripe fruit. I had always assumed the birds were taking them before they ripened, but now I believe they are male plants and the fruits never get past the hard, green stage.
Smaller plants are females. They produce soft black fruit with a skin so thin you often break it just by touching it. At full maturity the fruit exudes a clear substance and at this stage the fruit is one of the nicest eating bush tuckers and surprisingly rich in Vitamin C, energy and most minerals, with moderate levels of other nutritional elements.
The term "fruit" is actually incorrect. Botanists prefer to call them "syconium" or "fleshy receptacle", as they contain the flowers of the plant which must be pollinated by tiny, specialised wasps. A true fruit should derive from the ovary of a pollinated flower, rather than containing the flower itself.
Aborigines found many other uses for Sandpaper Figs apart from eating those heavenly syconiums. Of course, they used the leaves for polishing wooden objects, such as spears and boomerangs, and a quick look around will often find several plants with different coarseness of leaves. This was also used as a cure for ringworm. The skin would be abraded with the leaves and the milky latex applied to the area requiring treatment. This is apparently quite effective.
Dry straight stems of this tree were used for fire sticks and it is one of the few plants suitable for this purpose. If you do not have the right wood to start with, you will not even get the wood warm, let alone start a fire! The inner bark can also be used to make string.
So there you have it; a supermarket tree. It attracts birds, can be used for shade, food, medicine, tools, fire and string to make nets and traps. And some people call it a weed??
(Reproduced from "The Native Gardener", Newsletter of SGAP Townsville Branch, March 1998.)