Gas is very effective, but I wouldn't use it on a regular basis and of course care must be taken. What I've found effective and safe is diatomaceous earth. I make a ring of it around the house 3-4 times per summer. It has worked better than anything else especially chemicals. It is sold in 25 kg bags at my ag store. Also effective on isolated ant hills is a couple buckets of water with a bit of dish soap mixed in. The ants drown. It was explained to me that the soap bursts the air bubble around the ant, therefore drowning it. I live on an ant hill....... A very large anthill. Not sure if it will work on non-Alberta ants? Linda M Foulis Beautiful Blooms http://www.beautifulblooms.ab.ca/ >