Some 12,000 species of ants are crawling over the globe — more than 200 species in Florida alone! And sometimes it may seem like they’re all partying on your kitchen counter.

What do you do if you have an ant infestation?

The first step is to identify the enemy. Once you know what you’re dealing with, your tactics will vary. We’ve done your homework for you, identifying four of the most prevalent ant species that create trouble nationwide, and what to do about them.

Read on, so you’ll no longer be climbing the walls. And neither will they.

Argentine ants

Click to enlarge pictureAnt rant: Squishing the problem (© Odilon Dimier/ZenShui/Corbis)

Argentine ant (© Odilon Dimier/ZenShui/Corbis)

Know your foe: These 1/8-inch, all-brown critters are usually found marching, fast, in long, organized lines as they look for food. An invasive species, they can be found around the Southeast, but they’ve also gone nuts in California. “If you want to see an Argentine ant, just go to Southern California and look down,” says pest-control expert Mark Sheperdigian, vice president of technical solutions for Rose Pest Solutions in Troy, Mich.

Why exorcise them: Argentine ants don’t bite or sting, but are mainly a nuisance pest; they like sweet things and come inside looking for soft drinks and syrup, says Willie Chance, the University of Georgia College of Agricultural and Environmental Sciences extension agent for Houston County. But the little buggers are aggressive in their pursuit: They can get into food and be a contaminant. In fact, they’re so ardent in their pursuit that they can even keep aggressive fire ants out of an area, Chance says.

Stake in the heart: Act ASAP. Sponge invaders with soapy water as soon as you see them, and plug up ant entryways you see with caulk or petroleum jelly, recommend the folks at the University of California’s Integrated Pest Management program.

 © Karen Beard/photolibrary

Bing: Search & decide

Next, baits are one of the best ways to deal with Argentine ants, Chance says. “Baits usually take longer to work, but it takes it back to the source.” Here’s how bait works: A worker ant comes across it — imagine a morsel of candy-covered insecticide, if you will — and unsuspectingly carries it back to the colony to share. When many ants do the same, the colony dies. 

Chance recommends baits with slow-acting poisons like fipronil, hydramethylnon or sulfluramid. (Others also recommend bait — even homemade — of sugar, water and boric acid.) The ants will feed on them and take them back to the nest. Apply baits wherever ants are foraging and at a time when they are actively looking for food.

Keeping them gone: The key to keeping Argentine ants away is ensuring that the sweets-loving creatures are not attracted to anything in your house. Here’s some of Chance’s advice (and find still more here: .PDF file):

  • Stop the free buffet. Empty and rinse all containers before you toss them. Put garbage in sealed plastic bags.
  • No more honeydew. The ants love honeydew, the sticky-sweet stuff produced by aphids, scales and whiteflies. Choose plants that are not susceptible to these pests.
  • Don’t drown your mulch. The ants thrive outside in really moist areas. “Water once a week with one inch of water or twice a week with three-quarter inches of water,” he says. Don’t make mulch more than two to four inches deep. And keep beds away from the house.
  • Spraying: a last resort? If you do all these other things, applying insecticide to places like windowsills or around the base of the house may not even be necessary. But one product that shows promise in keeping the ants at bay over time is Over ’n Out. Though formulated for fire ants, it seems to work well for Argentine ants by forming a barrier atop the soil that controls ants that forage atop the ground, for up to several months, Chance says.

The DIY factor: “It’s decidedly true” that a homeowner can tackle this, Chance says. In fact, this is really something a homeowner needs to take on herself, because the Orkin man isn’t going to be there day after day to wash out food containers, keep the lid on the garbage can, etc.

Pharaoh ants, aka sugar ants

Click to enlarge pictureAnt rant: Squishing the problem (© Carol Buchanan/F1 ONL/age fotostock)

Sugar ants (© Carol Buchanan/F1 ONL/age fotostock)

Know your foe: Pharaoh ants are extremely small, orange-yellow ants. “If people have a hard time seeing the ant, and it’s a light color, it’s probably a pharaoh ant,” says Wizzie Brown, an extension program specialist in Austin affiliated with Texas A&M University.

Why exorcise them: According to the University of Florida, the pharaoh ant “carries the dubious distinction of being the most difficult household ant to control.” Pharaoh ants get into everything everywhere — from homes to bakeries to hospitals. They’ve even been discovered in hyper-clean DNA laboratories. That’s not good, because the ants can potentially transmit some nasty stuff, including salmonella. For most of us, though, the ants are just annoying because they have a knack for getting into everything.

Stake in the heart: “If you have a pharaoh ant infestation, you don’t want to use bug sprays on them because that typically ends up splitting the colony further and making them harder to control,” Brown says. Another mistake people make: Wiping up the counter and then putting down bait: That wipes out the invisible pheromone trail that the ants have been following, she says.

Here’s what to do: Don’t spray. Think like an ant, and put out a few bait stations, or gel baits, in the areas directly in the path of where the ants have been traveling.

The University of Florida also says that “nonrepellent baits (such as boric acid, hydramethylnon or sulfonamide) should be used, as repellent baits can worsen the situation by causing the colony to fracture.” (Read still more from the University of Ohio State University Extension here.)

Keeping them gone: They can establish lots of thimble-sized nests, so fighting these little buggers can be a long-term battle. Keep the baits out, directly in their pathways. And keep the house spotless to remove temptation, the University of California advises.  

DIY factor: “Try it yourself first,” Brown says, but if it’s a big infestation and the homeowners can’t control it with baits, “then they might want to contact a pest control company.” And remember: Don't mess with the colonies yourself.