We have had ant problems in the house every spring and summer and have had good success in getting rid of them by using Terro. It is now September and we have a new wave coming inside but this time of year they are not going to the Terro. What is the reason for this?
Greetings from the ant world!
Baits contain poison mixed with materials that attract ant foragers (i.e., worker ants looking for food or water). The ants will take small poisoned portions back to the nest (and eventually transferred to other nestmates, including the queen), and those will kill the entire colony.
Key points to use poisoned baits correctly:
1. The intoxicant used must be slow-acting, so the foraging ants have time to make their way back to the nest and feed other members of the colony before they are killed. Pre-packaged bait stations (like Terro) usually contain 5.4% borate, and they efficiently kill foragers in the home, but will take effect too soon and leave the queen(s) unaffected. Liquid borate products (derivate from Boric acid) with a lower percentage of active ingredient -- less than 1% of the active ingredient -- will have more impact on the colony, although it may take several days to a week to see results and they need to be used in larger, refillable bait stations.
2. Effectiveness of baits will vary with ant species; bait material, and availability of alternative food. Ant preferences, for example, can change throughout the year; to increase your success rate, set out different formulations of various bait products in a single baiting station, giving ants a choice. It would be something like a "cafeteria": simply line up a few drops (liquid foods are preferable because you can mix them evenly with the poison) of different kinds of food on some wax paper, and see what the ants go for (you can use peanut butter, sugary solutions, and pureed tuna fish).
3. Don't use any insecticide sprays while you are using baits, and check and refresh bait stations regularly. Baits can dry up or become rancid and unattractive over time. Also, to improve bait effectiveness, be sure to remove any particles of food, residues of sweet liquids, or other attractive material from cracks around sinks, pantries, and other ant-infested areas.
However, we, AntBlog people, just love ants - they are really amazing creatures, and have a lot to offer to our society (see here). Ants are, most of the time, good roommates, and will keep other insects out of your house; and you can observe, in the comfort of your home, how they interact with each other! Also, poison baits in your house will be a permanent risk for children and pets, and it can also contaminate wildlife and water supplies. If the ants in your house are unbearable, you can seal the cracks where the they are entering, vacuum up the ants, and apply boiling water in the nest entrance.
We hope this helps,
Flavia Esteves & the AntAsk Team