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This really really depends what type of ant.

Most you can just keep spraying til they give up, die off or decide somewhere else is more profitable.
Destroying their pheromone paths will prevent hungry returnees. Killing them in your house will prevent them returning to the nest to set a pheromone path to your comestibles.
Things which are smelly &/or sticky make good path-breakers. Vaseline they will not cross even though they can still smell the other side of the path. Hairspray works for a day, then loses its potency. Lighter fluid washes the path away, but doesn't prevent their return & is also a bit flammable ;)

Pharoah ants, on the other hand, can only be killed by feeding them with a hormone which prevents their breeding. If you try to kill/spray/squish pharaohs, they go into 'under attack' mode & all turn into breeding females & dissipate - not what you want - you will end up with tiny nest sites everywhere.
[This, strangely is not borne out by the wikipedia link - but was what I was told by the exterminator who came to rescue us from an invasion we were unable to deal with ourselves after 6 months of poisoning & the methods described above, which have been pretty successful on every other ant-type. It may have just been a poor or misinterpreted version of the 'budding' which that page does discuss - nevertheless, pharaohs need specific pharaoh 'poison'.]

This really really depends what type of ant.

Most you can just keep spraying til they give up, die off or decide somewhere else is more profitable.
Destroying their pheromone paths will prevent hungry returnees. Killing them in your house will prevent them returning to the nest to set a pheromone path to your comestibles.

Pharoah ants, on the other hand, can only be killed by feeding them with a hormone which prevents their breeding. If you try to kill/spray/squish pharaohs, they go into 'under attack' mode & all turn into breeding females & dissipate - not what you want - you will end up with tiny nest sites everywhere.
[This, strangely is not borne out by the wikipedia link - but was what I was told by the exterminator who came to rescue us from an invasion we were unable to deal with ourselves after 6 months of poisoning. It may have just been a poor or misinterpreted version of the 'budding' which that page does discuss - nevertheless, pharaohs need specific pharaoh 'poison'.]

This really really depends what type of ant.

Most you can just keep spraying til they give up, die off or decide somewhere else is more profitable.
Destroying their pheromone paths will prevent hungry returnees. Killing them in your house will prevent them returning to the nest to set a pheromone path to your comestibles.
Things which are smelly &/or sticky make good path-breakers. Vaseline they will not cross even though they can still smell the other side of the path. Hairspray works for a day, then loses its potency. Lighter fluid washes the path away, but doesn't prevent their return & is also a bit flammable ;)

Pharoah ants, on the other hand, can only be killed by feeding them with a hormone which prevents their breeding. If you try to kill/spray/squish pharaohs, they go into 'under attack' mode & all turn into breeding females & dissipate - not what you want - you will end up with tiny nest sites everywhere.
[This, strangely is not borne out by the wikipedia link - but was what I was told by the exterminator who came to rescue us from an invasion we were unable to deal with ourselves after 6 months of poisoning & the methods described above, which have been pretty successful on every other ant-type. It may have just been a poor or misinterpreted version of the 'budding' which that page does discuss - nevertheless, pharaohs need specific pharaoh 'poison'.]

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source | link

This really really depends what type of ant.

Most you can just keep spraying til they give up, die off or decide somewhere else is more profitable.
Destroying their pheromone paths will prevent hungry returnees. Killing them in your house will prevent them returning to the nest to set a pheromone path to your comestibles.

Pharoah ants, on the other hand, can only be killed by feeding them with a hormone which prevents their breeding. If you try to kill/spray/squish pharaohs, they go into 'under attack' mode & all turn into breeding females & dissipate - not what you want - you will end up with tiny nest sites everywhere.
[This, strangely is not borne out by the wikipedia link - but was what I was told by the exterminator who came to rescue us from an invasion we were unable to deal with ourselves after 6 months of poisoning. It may have just been a poor or misinterpreted version of the 'budding' which that page does discuss - nevertheless, pharaohs need specific pharaoh 'poison'.]