Strangling Fig

Strangling Fig, Ficus watkinsiana 

I've mentioned before how our park is flourishing. This Strangling Fig, Ficus watkinsiana, was planted about 6 years ago and is already a small tree. 

These trees are commonly seen in our area as forest giants in the national parks of Ravensbourne, Bunya Mountains and the Main Range. With their large buttresses, and lattice-like root system they are easily recognizable. 

Aerial roots

Figs are fascinating to me as they have some very unusual characteristics.

Normally strangler figs of this type grow high in the branches of other rainforest trees. This is known as being hemiepiphytic. An epiphyte such as an orchid growing on trees in the wild is a plant which grows on another but is not parasitic. A hemiepiphyte starts by growing on the plant until its aerial roots reach the ground and then becomes independent. In the Strangler Fig's case it surrounds the host tree which eventually dies. In cultivation it can be grown straight from the ground as it is in Peacehaven.

Unripe, green figs of the Ficus watkinsiana

The Ficus watkinsiana, like other fig species,  has both male and female flowers on the same plant. This is known as being monoecious from Greek meaning 'one house'. However you won't see them because they are actually inside the fruit! This seems very strange, but in true botanical terms the fig isn't really a fruit it is a cluster of hundreds of flowers enclosed in a smooth skin.

So they have to be pollinated in a very special way. Along comes the tiny fig wasp, Pleistodontes nigriventris. The female wasp, carrying pollen, squeezes through a minute opening in the fig which has two types of flowers. She lays her eggs in one type of flower, pollinating the other type at the same time. The young wasp larvae develop, and the adult wasps mate, inside the fig. The males are wingless and die while the females exit from the opening gathering pollen on the way. Each fig species has to be fertilized this way with its own species of wasp. The fig depends on the wasp and the wasp depends on the fig. By the way, there aren't any wasp eggs or remnants in ripe figs, because figs produce a protein-digesting enzyme that digests any waste left inside. By the time the fig is ripe, the wasps have done their work and flown away or were digested by the developing fig. This is just another amazing fact about figs.

A female Australasian Figbird eating a fig
in the Ficus watkinsiana

Cleaning her beak after her meal

Birds love the figs. In the dense rainforest the patter of half-eaten fruit falling on the leaf-litter alerts you to the birds in the fig trees. This happened to me at Peacehaven and I was able to photograph this female Australasian Figbird, Sphecotheres vieilloti, in the Strangling Fig.

Another bird, the Green Catbird, Ailuroedus crassirostris, is very important to Ficus watkinsiana. It carries the figs into the high canopy to eat. The seeds fall into forks and crevices in the branches successfully dispersing away from the parent tree. This is of mutual benefit to the fig plants and the catbirds.

Aborigines used the fruit, the bark and the latex for food, medicines and tools.

More about the Strangling Fig at the Noosa Native Plants website.

Ficus is the latin name for the common edible fig, watkinsiana honours George Watkins, former president of Qld. Pharmaceutical Society and plant collector.

There is more about George Watkins at the Australian National Herbarium website.