Personally I would dump the bin and pick out as many worms as you can to save them, and start over. I think anything you use to try to kill the ants might kill the worms. I had fire ants in my bin for awhile and they didn't seem to attack the worms, but raising ants isn't something you probably want to be doing. If you don't want to start over without a fight, you might try stirring the bedding thoroughly at least once a day to disturb the ants' nest-building. If they can't settle down and make babies, they might move out. Putting a few ant baits near the bin might help but I would still worry about the ants bringing poisons into the bin. I did the baits and the stirring and eventually the ants moved away, but it took a very long time (months).
I agree with Ludi. When you get invaders in your bin it's time to pick out some stock and start over, dump the rest in the chicken area and they'll take care of the ants.
Consider a new location for the bin as ants follow pheromone trails and established patterns of movement. If you cannot move your bin then I would do something to the ground all around the bin. Break it up, then spray well with vinegar or lay down DE. Anything to mess up those established ant trails or they will just come back.
posted 9 years ago
diatomaceous earth wont hurt earthworms but does kill most ants .. and you cant eat it so not so much a posion sprinkle some in
Location: Lower Mainland British Columbia Canada Zone 8a/ Manchester Jamaica
posted 9 years ago
It's a bit late to comment now, but what about an ant repellant like tansy in your worm bin? That may not work for fire breathing ant's, but you could herb stink em out. As long as it's not an allium or a citrus it wont hurt the worms. I can't imagine having to empty out my 800 lbd worm bin because of a creepy crawly breakout, the stress of trying to retried worms would be impractical without a worm harvester.
Unfortunately, in my experience here in Florida fire ants LOVE any opportunity to make a nest where the rain won't fall on them. Under a tarp put there to solarize a patch of soil, inside a forgotten flower pot. A worm bin would be that and food, too. AND they do kill worms... at least that's what I've heard. I don't think I've ever seen a worm here in the South (of the USA).
A moat of water might keep the ants out (I'm thinking of putting the bin in a kiddie pool with some water in it), but then you would contend with having just made mosquito heaven. Maybe some frogs in the pool or some fish to eat the mosquitos would take care of that. You would need to put some thought into the worm bin to get it to work in places like this.
BTW for those not familar with fire ants, they get their name because they carry a bee-like sting. When you are careless enough to step on their mound they come racing out, and after climbing all over you, attack you all at once.
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