I have ants nesting in my garage wall. Our garage has a concrete floor, and the wall is cinder block for the first eight inches (I guess just one course of brick), with an insulated stud wall above that. There is drywall on the inside of the studs, but it ends where the brick starts, i.e. about eight inches above the floor. I haven’t actually seen any ants in the garage, but they are dropping their frass through the gap between the drywall and the brick: if I sweep the garage floor, a couple of days later there will be smal piles of sand there. It’s definitely sand/soil and not sawdust, and so one of the pest-control guys I called says they are slab ants, AKA pavement ants. These are the same ants frequently seen creating little dirt cones at sidewalk cracks; they excavate below grade to make room for their nest, and discard the mined soil just outside the entrance.
As I haven’t actually seen any ants in the garage, the colony appears to be completely contained within the wall (I guess they have access to the great outdoors, though I haven’t seen where), so I don’t have a good idea of how to attack it. I decided to call the pros, but I’m a little bugged (!) by what I’m hearing.
Terminix wants to sell me an indefinitely long series of quarterly treatments, $180 each, to protect against just about every conceivable household pest. When I asked how many treatments were required to wipe out the ants, he said “about” two.
Orkin wants to apply four quarterly treatments, claiming that’s what is required to break the life cycle of a colony of slab ants.
What’s the straight dope? What sort of treatment is needed to rid a house of slab/pavement ants? Do I really need four quarterly applications of something, or “about two?” Is there a single application treatment that I can use? I don’t mind paying for an effective professional treatment, but I want to know what’s really needed first.