When people talk about getting rid of black ants, they are generally referring to one of two different species. The first is the carpenter ant (read: how to get rid of carpenter ants). The second of these, which is the one we'll be discussing in this article, is the little black ant. Yes, that's what they're actually called. Blows the mind, doesn't it? Anyway, little black ants (Monomorium minimum) are excruciatingly annoying and numerous pests. A single colony can consist of more than 2,000 ants that are active both day and night. They can be found in yards and houses all over the United States, especially the eastern half of the country and southern California. And from what I have gathered thus far, these small ants aren't really welcome anywhere.
The biggest difficulty we face with little black ant control is that they are so versatile. They will nest in almost anything. Outside they will be in the ground (you've seen the little craters that mark the entrance), in trees, in mulch, in cracks in sidewalks and driveways, in rotted wood, under rocks, etc. Inside, black ants will nest in woodwork, masonry, wall voids, and even under carpets. When it comes to food they eat, forget about it. They eat everything. Favorites are sweets, vegetables, fruits, meats, dead insects, plant secretions, and grease. They'll even eat honeydew, which is a secretion given off by plant suckers like aphids and scales. They don't eat their chow right where they find it, though. Following little scent trails that they leave, they collect the food and drag it back to their nests. They can drag some pretty big stuff, too—up to 20 times their own weight. Despite their colossal strength, getting rid of black ants isn't all that difficult. The problem is that it's pretty much always temporary. Once gone, you can count on them coming back at some point. At least you'll have this article to refer back to. Whether this is your 1st or 30th time dealing with these tiny black ants, let's get rid of 'em.
Black Ant Control
Start with a clean house. As I mentioned above, a little black ant will eat anything and everything. So do your dishes. The little bits of food that get left behind on dirty dishes, pots, pans, and silverware make a darn fine meal for a black ant. Wipe stoves, countertops, and tables diligently after every meal or snack. Crumbs on the floor are tasty too. Develop an obsessive compulsive habit of sweeping, mopping, and vacuuming. Also remember to take your trash out regularly and to rinse out bottles and cans before ants can find them.
Protect your food stuffs. Even if your kitchen is spotless, little black ants can and will invade your home in search of a meal. Don't give them the satisfaction of finding unsafeguarded food. Store everything in tight containers, preferably plastic containers with snappy lids, tin/aluminum canisters, or jars with rubber gaskets. This includes, but is not limited to, flours, sugars, pastas, cereals, chips, butter, and oils. Basically assume that if it's something you can eat that the ants would also like to eat it.
Gather a search party. Before you start to kill ants all willy-nilly, you should probably make sure you know where they're coming from. It's just nice to know if they are camping out inside your home or if they're sneaking in from the outside. By having this information, you will be able to target the colonies more effectively later. When you see ants inside, watch them for awhile and see what little nook or cranny they are retreating back into with their bounty. Spend some time outside looking around for ant colonies too.
Fill all the cracks. While you're looking for ants outside, if you see some, pay attention to how they are getting in so you can block that opening off with some caulk. Even if you didn't see any ants out there, you'll want to look for openings anyway. They got in there somehow, and once you get your current black ant infestation under control, you'll want to avoid future ones. So walk around out there with your caulking gun and fill any cracks in the foundation along with any openings that may have been created from bringing in electrical wires, cables, phone lines, plumbing, etc. Not only will this help with controlling black ants, it's an important step in controlling almost every other type of house pest as well (see: pest control).
Find and remove any debris. While little black ants do sometimes live in your home, more often than not they have a nest outside somewhere and are just using your home as a food shelf. Outside the home, look for and remove any decent sized rocks, logs, pavers, stepping stones, stumps, mulch, and anything else that looks like something black ants might like to live under. It's also a good idea to trim back tree and shrub branches that are up against the house. Black ants will sometimes use these to get to your house.
Commercial Ant Bait, Ant Spray, and Ant Poison
People who are trying to figure out how to get rid of little black ants are in luck. Because black ants are such a common problem, ant poisons are super easy to come by. They can be found online, at the hardware store, or at pretty much any of the "Mart" stores. They come in a number of effective application methods such as baits, poisons, and sprays. Below, you will find a few suggestions for each type.
Ant Baits. Because black ants gather food and take it back to their nest, ant baits are probably the most effective, easy to find, and easy to use form of ant killer. Ant baits don't kill ants immediately, which allows them to take it back to the nest and infect the entire colony. Ant baits are generally applied or placed directly in the ants' scent trails. Look for products such as Gourmet Ant Bait Gel, Advance 375A Select Ant Bait, Advance 360A Dual Choice Ant Bait Stations, or Maxforce Ant Bait Stations.
Ant Sprays. Ant sprays are a convenient way to kill black ants outdoors. Mix it up, put it in a sprayer, and let the genocide begin. This is the best method for hitting those colonies that have taken up residence in your mulch or yard. If you did as I suggested above and spent some time looking for colonies, you'll have a pretty good head start. Give the colonies a good direct spray and give the perimeter of your house a once-over while you're at it. Many sprays have good residual control. Look for Suspend SC Insecticide, Cynoff EC or WP, or Demon WP.
Ant Poisons. For inside the home, after you've figured out which crack the ants are disappearing into or you've discovered the wall void they've set up camp in, you might as well throw some poison at them. There are several aerosols that work well for this. Check out CB-80 Extra, D-Force HPX, CB Intruder HPX, or Microcare Aerosol. For these same situations you may also choose to place or blow some dust into the cracks. Look for Drione Dust, Delta Dust Insecticide, Tempo 1% Dust, or EcoExempt D.