How to Kill Ghost Ants

Ghost ants are members of a tiny invasive species that derives its name from the milky white, almost translucent, color of the ant's legs and abdomens. The color makes them difficult to see. Thought to have originated in either Oriental or African tropics, these ants are sometimes called black-headed ants or corpse ants and are known to release a coconut-like smell when crushed.

The ghost ant is considered a trap species and was introduced to the United Sates through human commerce. Though well established in Florida and Hawaii, its range is expanding. Ghost ant populations have been found indoors in Texas, Iowa, Oregon and Canada. Though the ghost ant becomes weak in the cold, it has been able to adapt and thrive in northern areas by living in greenhouses and warehouses. Colonies of ghost ants are very adaptable and highly mobile and can be difficult, but not impossible, to eradicate.

Ghost ants thrive in tropical conditions and can be found in warmer regions nesting in the ground next to stones or logs or under firewood piles. In cooler Northern states, the ants are only known to survive in heated buildings or greenhouses where they feed on honeydew collected from aphids on plants. In homes, they will often nest in voids between walls, behind baseboards or in flower pots and are known to split their colonies into several nests with several queens.

Outside nests can be treated with a residual insecticide by using a pump sprayer to soak the ground and other areas that show signs of nesting. While this will kill the foraging ants it could cause stress on the colony forcing them to split and scatter into sub-colonies making matters worse. Locating and completely destroying the nest is the most direct way to eliminate a ghost ant infestation. The use of a contact insecticide spray that is specifically labeled for ants will kill the workers in visible nests but it’s only a partial solution.

Since ghost ants form several nests, the use of bait tends to be more effective in eradication than insecticide sprays which can kill the ant before it can return to its nest and poison the others. Ghost ants favor sweets so baits with a sugar or honey base work best. Ants follow chemical trails and transport food back to their nests so a sweet bait consisting of 1 to 5 percent boric acid in a sugar or honey water solution will provide the worker ants with a toxic meal to take back to the nest. Boric acid works as a slow acting stomach poison, and with this method, you can kill the entire colony within a few weeks.