DEAR TIM: Two days ago I ate a piece of watermelon before I went to bed and accidentally left the rind on the kitchen counter overnight. I woke up to find my kitchen invaded by small, black ants. They were everywhere! The little devil ants were crawling all over my counters and in my sink. The melon rind had several ants on it. I killed them all, and immediately took the rind out to the trash. It is two days later, and I am still seeing black ants. What can I do? I am fighting a losing battle here on the Outer Banks of NC. Teresa P., South Nags Head, NC

DEAR TERESA: The ants are just a nuisance. They can't harm your home, and they are just simply unwanted house guests much like some of my relatives and in-laws. The small ants were simply looking for some food, and were attracted by the sugar in the watermelon juice.

Ants are amazing insects. They have very structured colonies, and certain ants have very distinct jobs. All ants need to eat, and certain ants within the colony are the primary energy providers. Their responsibility is enormous as they are charged with finding food for the other colony members. These ants scout randomly for food, and are attracted by fragrances and food particles. Once they locate food, they communicate the findings to other ants within the colony.

These ants that explore the land around the colony were looking for food and knew to come to your house. There is a good chance they had been in your home before, and my guess is they found some small crumbs on the kitchen floor. The reason the ants came back is because they had left a chemical marker trail behind. These marker chemicals are called pheromones.

But this time they struck gold with the sugar-rich watermelon juice. This high-energy food source caused them to scamper back to the colony to announce the find while you were sleeping.

My guess is that once you killed the visible ants, you washed the countertop off. This would have removed the chemical pheromones from the counter, but the chemical trail was still on the floor. The survival programming within the ants kept telling other ants to come to your kitchen to get more watermelon juice. After all, they were unaware you had thrown it away once you decided to get up out of bed.

If you sweep the floor well, and then mop the floor with a solution of ammonia and water, you will stop the invasion of ants. The ammonia will remove the pheromones, and it will act as a powerful repellent to the small ants. Start with a solution of one part ammonia to one part water. If the odor of the ammonia is too strong for you, then cut the solution back to one part ammonia to two parts water.