15/09/2026
When the Termites Leave, the Fungus Takes Over
Over the last couple of months, we had been treating a home in Chambers Flat (South of Brisbane) for active termites. During a follow-up inspection after a Termidor foam treatment, we found something particularly interesting inside the termite workings.
When we opened up the affected area, the termite workings were covered in a thick, white, cobweb-like growth of fungal mycelium.
This raised an interesting question: if fungus can grow so readily through termite workings, why don’t we normally see it when the termites are still active?
Termites live in an environment full of microorganisms. Timber naturally contains bacteria and fungi, and termite workings can provide warm, humid conditions where fungi can thrive. Yet when we open up active termite workings, it is quite common to find little or no obvious fungal growth.
One reason may be that termites are constantly maintaining their environment. Termite saliva, faecal material and nest materials can contain substances with antimicrobial and antifungal properties. Termites also groom each other, remove waste and damaged material, and generally keep their workings maintained.
This doesn’t mean that termite workings are completely free of fungus. Rather, the termites’ constant activity may help control or delay visible fungal growth.
This is quite different from the specialised fungus-growing termites of the subfamily Macrotermitinae. These termites deliberately cultivate fungi from the genus Termitomyces as part of their food system. The termites we commonly encounter around Brisbane, such as Coptotermes and Schedorhinotermes, do not generally farm fungus in this way.
So what happens when we treat a termite colony?
Once the termites stop occupying the workings, their housekeeping stops too. If the workings contain moisture, timber particles and other organic material, fungi can quickly become much more noticeable.
We’ve particularly noticed this after foam and liquid treatments, where termite activity can stop relatively quickly. With dusting or baiting, the process of colony elimination can take longer, so the termites may continue to occupy and maintain their workings for some time.
The appearance of fungus doesn’t necessarily mean the treatment has caused a fungal problem. In many cases, we’re simply seeing fungal growth that has become more noticeable because the termites are no longer maintaining the area. Moisture, temperature, ventilation and the condition of the timber can all play a part.
This is another reason why a follow-up termite inspection is so important. We’re not just looking for live termites; we’re looking at the evidence they leave behind and the changes that occur after the colony has gone.
When termites are active, they continually modify and maintain their environment. When they leave, that environment changes - and under the right conditions, the fungus can take over.
It’s a fascinating reminder that a termite colony is much more than insects eating timber. It is a complex little ecosystem involving termites, microorganisms, fungi, moisture and the timber itself.
And sometimes, when the termites are gone, the fungus tells us part of the story of what happened next.
