This morning Sass discovered the beginnings of an ant invasion in the dog food. It was definitely only a beginning, as there were probably only about 50 or so.
We've always kept the dog food in the same spot by the back door for the four years that we've had them. Always. I suppose we're lucky in that this was the first attempted invasion.
We struck strongly and swiftly, moving everything outside, then dousing with the spray that I've kept on hand just in case. We let it sit for a bit while we took care of the ones we'd taken outside, then came back in and mopped with the Power of Pine Sol.
Thankfully, I've always kept the dog food in sealed containers so it wasn't contaminated by the ants at all. But now I will be fully alert, on guard against the next attack.