Ghost Ants Can Be More Trick Than Treat For Homeowners

October 29, 1997

GAINESVILLE— Florida homeowners may be haunted by more than the usual ghouls and goblins this time of year as ghost ants show up in kitchens in search of a sweet treat.

Ghost ants are pesky little insects who got their name by looking much like tiny, white apparitions who suddenly appear and seem to disappear just as quickly. They don’t sting or bite, but like any good trick-or-treater, ghost ants do have a sweet tooth and prefer nibbling on goodies such as cakes, candy and cookies.

Phil Koehler, an entomology professor with the University of Florida’s Institute of Food and Agricultural Sciences, said ghost ants are both fast and small, averaging about 1 mm in length, or about the size of a pin head.

Ghost ants are most deserving of their name, Koehler said. With a black head and thorax and a pale, gray body, they are almost transparent, move quickly and are hard to track.

With no effective method for eliminating the critters, a home can be overrun with little ghost ants in no time, said David Williams, an adjunct professor of entomology at UF.

“They are often found in plant material brought into your home. They generally live in just about anything outdoors — in plants, plant products, wood and soil,” Williams said. “In the indoors, they can move into interior walls or live in book bindings. They can live just about anywhere.”

He said the search for a way to eliminate ghost ants is as elusive as the pest themselves.

Over the past few years, Williams has been trying to develop baits to attract ghost ants and kill their colonies. He said they are testing an attractant now, but there is no effective bait or insecticide at this time.

Koehler said some liquid baits containing boric acid available over the counter can work well, but should be diluted so the ant has time to get back outside to the colony before it dies. The best thing for homeowners to do is to track where ghost ants may be entering the home or building and seal off the opening to keep the ants outdoors, Koehler said.

“We could turn these ghost ants into real ghosts by killing them, but the baits need to work slowly to affect ghost ants. Because they are so small, a normal bait would kill the ant too fast before it could get back outside,” Koehler said. “Consequently, most baits we have now don’t work well because of their high dosages, which kills the ants before they can get back to the nest to the others.”

Koehler said ghost ant sightings occur mostly in warm climates and can be a big problem in tropical areas of the world. In Florida, they are found mostly from Orlando south, although they do occur as far north as Gainesville.

A good ghost? Although they can be a pest, they also can be beneficial in certain instances. For example, Koehler said, they do prey on and control mites that attack plants.