Leaf Cutting Ant Forum

Acromyrmex octospinosus, and probably many of the other Acromyrmex species, do not simply rest their fungus on the floor of the nest chamber they have dug. New queens excavate a chamber approx 4cm diameter and attach their fungus to a root passing through the nest chamber. The fungus initially grows without touching the side soil of the chamber and as a result is not exposed to potential harmful pathogens and disease. Therefore new incipient colonies of Acromyrmex should have a nylon string suspended through the nest container. In experiments conducted with this setup, 60 out of 60 queens attached their fungus to the nylon thread instead of leaving it on the ground! Quite conclusive. This should be a standard part of the setup employed when raising colonies from queens.

I have read the same in an article somewhere and both my new fungus gardens were started off in the same way utilising a green plant cane to begin with. But this was done by the workers and not the queen, so perhaps not just in new colonies.

Fantastic pic, Andy!!
Yes, this is interesting, potentially very helpful, if not critical, in starting new colonies and successfully growing them on.

This is really interesting, I've witnessed them building on twigs myself. Is this something you will now incorporate into new colonies you bring over Andrew?

I think that should definitely be looked at as a possible enhancement of the nest boxes. Although I suspect that this behaviour will stop once the fungus grows to fill the chamber. The size I work with the fungus generally is sitting on the soil. This measure is, I am sure, seen mainly in very small incipient colonies.

So what happens to the nylon thread once the fungus has past the initial stage? Do you just remove it or keep it there?

Definitely keep it. So many times when I am excavating Acromyrmex, their chamber is full of roots which go through the fungus. I am sure the ants use these to stabilise and strengthen the structure of their fungus. The ants are perfectly capable of trimming these and clearing them away after a time but they never do (Acromyrmex). However I have never seen Atta use this technique. Likely this is a more primitive technique.

Thought I'd post these pics up. My new unit attached to a make shift forage and dump. As you can see it's just a heat cable lay loose with a towel over. Have no clue of the temp.
Anyway woke up to this.





They may just prefer tub to the box or just want a second garden.
Or they may just want to build on sticks which is inline with Andrews thread. We should maybe start advising New keepers with young Acromyrmex colony to make sure they add privet branches in beside the young colony.

Maybe a little disappointing or maybe your Acros are simply enjoying the new space. Whats the inside or the box looking like? Is it full?

Far from being full, I think when it is it will be a nice sized colony. Acromyrmex are tricky wee buggers, they always give me more grief