When their nests can't be found, what works to control household ants such as Pavement ants?

Using liquid, gel, or granular ant baits is effective for controlling household ants, such as pavement ants, especially when their nests are difficult to locate. Ant baits are designed to attract ants, which then carry the bait back to their colony. This method targets not only the worker ants that you see foraging for food but also helps eliminate the queen and other members of the colony, leading to a more comprehensive solution to the infestation.

The key to the efficacy of baits lies in their formulation. Many baits contain slow-acting insecticides that allow ants sufficient time to return to their colony before succumbing to the poison. This delayed action is crucial for reaching the queen and other ants that might not have been directly exposed to the bait. As a result, the population decreases more effectively compared to using pesticides that might only kill visible ants without addressing the source of the problem.

The other options include direct methods that may not offer the same level of effectiveness in controlling the ant population in the long term. For instance, sprays may kill ants on contact but do not provide lasting protection as they don't minimize the colony's size, while traps with pheromones attract ants but often do not have the same lethal impact as bait that targets the queen.