||05-09-2005 11:22 AM
While I'm not an expert... I Have dealt with carpenter ant - the most effective was buying a bottle of the powdered boric acid mix (often sells as roach killer - and I think the rest of the mix is a silica that scratches their ectoskeletan). I sprayed (it's a squeeze bottle and the powder sprays out) a thick line in their path - or large circle - and as I understand how it works they walk through it and they don't clean up until the get inside their nest - where they start spreading it about - I think it just removes water from their ectoskeletan.
I'm sure it works best if you put it out on a dry day. I also prolly went overboard and sprayed over their mound as well. I seen only 1/16th as many as when I moved in in 2000.