A tablespoon or two of carbaryl dust dumped right at the main entrance hole (at night, of course, and use a red headlamp light etc., nothing bright) will put the hurt on. They carry the dust inside the nest and get it all over the place, but it doesn’t alarm them like spray cans of insecticide do.
Wait a couple days to see activity die down, might need another application. Eventually the queen will die which will kill the colony. Any stragglers can be handled with spray cans.
There are some YouTube videos [0] that show the idea of using carbaryl dust that might be helpful. An insecticide dust applicator would be the perfect thing to use, but all I did was slowly march up to the hole and dump the dust from a cup right onto it.
