The trail is your delivery system
The ants crossing your worktop are foraging workers, a small fraction of the colony. The queen and brood sit in a nest that is usually outside the room — under a paving slab, in a wall cavity, beneath floor insulation or behind a skirting run.
Because you cannot reach the nest directly, you use the workers: place gel bait on the trail, and they carry it back and share it by trophallaxis until the brood and queen are dosed.
- Never wipe the trail away before baiting — the pheromone line is what guides workers to your bait.
- Follow the line to the entry point before deciding where to apply.
- Kill sprays remove workers and leave the queen laying; the trail rebuilds within days.
Where to apply indoors
Place small dots directly beside the trail rather than on top of it, at intervals along the route and heaviest at the entry point. Typical indoor entry points are the silicone joint behind the sink, the gap where pipework enters the wall, the underside of a window sill, and the junction where skirting meets the floor.
- Entry point: two or three dots within 10 cm of the gap.
- Along the run: a dot every 30 to 50 cm on the route to the food source.
- Food source: bait beside it, then remove the food so the bait becomes the attraction.
- Keep dots in cracks, hinges and voids, away from open food-contact surfaces.
Expect a rush before the drop
Within an hour of application the trail often gets busier, with dozens of workers clustered on the bait. That is exactly what you want — heavy recruitment means more active ingredient reaching the brood.
Activity typically drops off within 24 to 36 hours and the trail disappears over the following few days as the colony collapses. Replace bait while it is still being taken.
Everything below assumes a professional-strength bait — our ant killer gel kits ship with the applicator and placement map referenced here.
Stop the next colony
Once the trail is gone, seal the entry point with silicone or filler, and remove the reason they came: wipe down sugary residue, keep pet bowls clean and dry overnight, and store opened sweet goods in sealed containers.
In summer, expect fresh scouts from outdoor nests. A few dots kept at known entry points stop a scouting ant from ever laying a full trail.