In my garden I think it usually happens over about a week at the very most. As the survey found, it happens late afternoon and when the weather has been especially hot and with hardly any wind.
And yes, Chubb, it pains me to say this, but ants(along with wasps), irritate the heck out of me!
Edited by ouija ouija, 17 October 2012 - 02:09 PM.