Termite Attack (1990)

[Images flash through of different termites at work inside a termite nest]

[Image changes to show Dr John French]

Dr John French: I think we have reached the point where we want to have the minimum amount of pesticides, A) to humans and into the environment.

[Music plays and text appears: The Researchers]

[Image changes back to termites at work in a termite nest. Image changes to show a hand turning over a board with termites underneath]

Narrator: In Australia, we all get used to creepy, crawly things. Ones that bite, ones that simply frighten and ones that destroy.

And our modern day solution? - SPRAY! But in many cases the cure may be more harmful than the problem.

[Image changes to show pesticide being sprayed over an area]

[Image changes back to Dr John French]

Dr John French: The chemicals they use because of the nature of the problem, they normally have a long residual life, which is bad news, in the sense for polluting the environment - not only for the people but also for the environment itself.

[Image pans out to show Dr John French inspecting a termite nest]

Narrator: CSIRO's Dr John French believes that understanding your enemy is the best solution.

[Camera zooms in on a termite damaged piece of wood]

His speciality is termites, a creature that, each year, causes around 100 million dollars’ worth of damage to buildings in Australia.

[Image changes to show Dr John French driving through the bush in a white Toyota Land Cruiser]

Dr John French: Because I used to be a forester, I now see the role that they play in forestry; they’re all part of this rather rich cycle of life that you find. So, sure, it's a dynamic study.

[Image changes to show the inside of an active termite nest]

Narrator: Termites have a highly developed society. Each colony has a queen, king, soldiers, reproductives and workers. The queen is little more than an egg factory creating thousands of eggs a day for up to 50 years.

[Image zooms in on the queen ant with the worker ants surrounding her]

The workers do all the labour while soldiers fiercely ward off predators. And there's no fear of revolution - the winged reproductives or alates, take off when they're old enough to start their own nest.

[Image flash through reproductive ants, the queen ant, the worker ants and then the soldier ants at the entrance to the nest. Images changes to show the winged reproductive ants flying from the nest]

[Image changes to show the outside of a termite mound and the camera travels up the termite mound. Image then pans out to show Dr John French working at the termite mound]

Understanding this regimented society is the key to keeping them under control.

[Image changes to show worker ants foraging for food in the grass]

The workers forage for food away from the nest and very few barriers can stop them - they have been known to get through fine cracks in concrete slabs.

[Image changes to show Dr John French pouring different size gravel into lunchboxes then placing cork pieces on top of the gravel]

A simple method for keeping them out of buildings would be to build on a barrier they can't penetrate.

Dr French is experimenting with a non-chemical barrier using different sizes of gravel. He serves up irresistible pieces of cork to the termites in these lunch boxes. Before they can feast on the cork, however, the termites have to burrow through a layer of gravel.

Dr John French: Well this is the fine grain, so this is less than 1.2mm diameter.

[Image zooms in on Dr John French’s hand displaying fine gravel]

They can just push their way through and cement a tunnel system. So they get through that no trouble.

[Image zooms in on Dr John French’s hand displaying larger gravel]

The larger grain, they don’t lock together, so there are lots of little spaces for them. Although it’s heavy, they can weave their way in between the spaces and cement a tunnel system.

[Image zooms in on Dr John French’s hand displaying a the termite proof gravel]

But the one that we’re really checking out, this is the dimension that we found that they can’t push through. They’re too heavy for the individual termite to lift themselves and they’re too tough and they cannot chew it so that’s why that’s a barrier.

[Image changes to show Dr John French exiting the Toyota Land Cruiser and walking through the bush to the termite mound and checking the boxes]

Narrator: Dr French leaves the boxes in the termite mound for a few weeks before coming back to check the success of his experiment.

[Image shows Dr John French opening the lunchbox. Camera zooms in on the inside of the lunchbox and shows an image of the termites eating the piece of cork]

Dr John French: They’re obviously able to cross this very fine material and there they are. They’re having a great time chewing into that piece of cork, a lot of activity there.

[Image then shows Dr John French inspecting another lunchbox. Camera zooms in on the inside of the lunchbox and shows the termites at work in the cork]

OK, now this is a one with a coarser material and yet they’ve just got to the edge here.

[Image shows Dr John French inspecting a third container with coarser gravel and cork but no termites]

Now here we have the grain size that we wouldn’t expect them to come through and they haven’t tunnelled up through. There’s nothing, that’s good.

Narrator: Building your house on the right size gravel to act as a barrier seems like a simple solution. The best ones often are.

[Image changes to zoom in on termites in a petri dish]

Another treatment being refined is based on the knowledge that worker termites are tactile creatures, always touching and grooming each other.

[Image zooms out to show gloved hands dusting a worker ant with poison inside a tube then replacing it into the petri dish with the other worker ants]

[Image zooms in to show worker ants all rubbing against the poisoned ant and then worker ants dying]

Here in the laboratory, 50 workers and ten soldiers have been set on a trail. One worker has been dusted with poison. Soon because of the constant touching, the other workers are affected. Within four hours all are either dead or incapacitated.

It means the poisoning of a few selected termites can be more effective than indiscriminate spraying.

[Image has changed back to Dr John French]

Dr John French: You’re right on the target beast. You’re not spraying chemicals hither and yon, to stop a termite walking around because other insects may be walking and little people.

[Image changes to show Dr French placing small blocks of wood on a piece of cardboard]

[Image changes to show Dr John French placing the blocks of wood into a wall cavity. Camera zooms in on termites working inside the wall cavity]

Narrator: Dr French's experimental method of poisoning the termites is to impregnate small wooden blocks with toxins and place them in wall cavities. The termites eat the wood and carry the poison back to the nest to destroy the colony.

[Image changes to show Dr John French taking blocks of wood from plastic bags and placing them into a wall cavity]

It obviously has to be done with great care and few are licensed to handle the toxins.

Dr John French: The poison in the block is a chloro-carbon called Mirex but it’s in very small amounts. I’m only using less than two grams of material.

Narrator: And when the colony of termites is dead, usually after a couple of weeks, the impregnated blocks are removed leaving no chemical residue.

[Image changes to show a trowel scraping up the block of wood eaten by the termites]

And so for Dr John French, relying on chemical sprays is not the solution.

[Image changes to show person spraying around the base of a house]

[Image has changed back to Dr John French]

Dr John French: The problem is of course, with that it’s like a technological fix. It narrows your vision and it narrows your options but the main problems of course, it pollutes a) the person who does it, the people who live in the situation after it’s been treated and of course the environment. So we have decided to look for softer, gentler, environmentally sounder methods of using it, rather than the chemical alone.

[CSIRO logo and text appears CSIRO AUSTRALIA – MCMXC]