Ciao @sirenahippie - thanks for the very interesting post! I've had to deal with big movements of ants who love to come and shelter in my home, for years, and I use bicarbonate of soda every time: a thin line of it across doorways and along the routes that they're using. It might not be entirely neighbourly of me, and I know it is toxic to them, but it is not practical to have thousands of ants busying about my home and kitchen... I make sure to warn them first, and ask them to leave voluntarily and to use another house (there are plenty around which are already abandoned and so they wouldn't be bothering anyone there!)... Good luck dissuading them.
Hello @clareartista I'm sorry to be so late for such a great comment. I'll try to do that too, it can be a good alternative and I know it won't be toxic to the terrain. Thanks a lot for the suggestion. Greetings.