Moisture Ant: Facts, Identification & Control
Moisture ants get their name from their habit of nesting in high-moisture areas in homes. Some people call them yellow ants because the workers are yellowish in color. One of the largest is Acanthomyops interjectus (Mayr).
These ants usually nest in the ground. Outdoors, they often nest under rocks or logs. They make a mound of soil as they dig their underground galleries. They sometimes nest above the ground in rotting logs.
Moisture ants feed on honeydew. The workers get honeydew from aphids and scale insects that feed on plant roots. Moisture ants often tend aphids to collect the honeydew that they produce.
Some moisture ant colonies make their nests against the foundation of homes. When colonies are under slabs, the ants often push soil up through cracks in the concrete while they are digging galleries underneath. When this soil appears in basement floors, it can cause distress for the homeowners. Many people mistake this soil for a sign of termite activity.
When moisture ants move indoors, they often nest in wood that is decayed by fungus. They frequently find damaged wood in areas like bath traps. They sometimes nest inside walls where there is a plumbing leak. There have been cases of these ants nesting in damp soil in crawlspaces. In these situations, the workers made mounds of excavated soil in the crawlspace.
If the ants have nested in damp or damaged wood, correcting the moisture problem and replacing the wood will be a priority. In damp or humid areas, treated wood may be a good replacement.
If winged ants have swarmed inside the home, remove them with a vacuum cleaner. Empty the vacuum bag promptly and take it outside to the trash. It is sometimes hard to tell whether winged insects are ants or termites. Call the local pest control professional for an inspection and identification.
Liquid insecticide can be effective against nests of moisture ants. Drenching the nest directly with the insecticide will provide the quickest control. If the ants have nested under a slab, it may be necessary to apply insecticide under the concrete. The local pest control professional has the equipment necessary to make these applications.