HEY peter I was just reading your cutter ant post!!!
I just read that and one part hit me as funny where you wrote about trying to dug them up to find the queen. maybe so if they had not been there but a very very short time. I have a lot down the road which is around 7000 meters, and cutter ants in 4 lines going from end to end bring back all kinds of flower and leaves, I followed them back to the hole they were going down and declared WAR!!!! I thought hum I'll burn em out.. I filled a 5 gal gas can and poured it down the hole. yep I did... lol I poured a small line of gas far back away from it and threw the match.. boom!!! yeah baby take that.. next day I went back and the same lines were going about their everyday life, but going down another hole not far from the first one. hummm so I did this again. and again and again. I have yet to see that I have made a dent on these guys.
searching the net one day I came across this little video and after you watch it you'll understand why I was laughing at your idea to dig the queen out and of course at myself for wasting 20 or so gals of gas!!! lol check it out. http://www.youtube.com/watch?v=ozkBd2p2piU