Citronella ants are small, yellow ants that nest and build colonies near areas of high moisture, such as logs, rocks, behind bathtub walls, and even in damp crawl spaces. They are approximately 4 mm in size while queens are about 8mm and emit a very strong citronella smell when crushed.
Also called yellow ants, citronella ants are primarily nocturnal, most swarms occur in early-to-mid-spring and their diet primarily consists of honey from underground pests. Citronella ants tend to enter homes from cracks in the foundation or through sub-slab heating ducts. You primarily see the winged reproducers, called swarmers, foraging in homes. Because of their similar behavior and appearance, citronella ant swarmers are sometimes mistaken for termites.
Outside, citronella ant nests are usually located in the soil adjacent to structures, along foundation walls or under rotten logs. Dirt mounds from the excavation of their tunnels can reach up to three feet in diameter.
How Citronella Ants Infest Homes
Although citronella ants don't build nests inside homes, they do sometimes wander in through open doors and windows and swarm inside from soil that houses their colony. Occasionally, citronella ants found in crawl spaces and basements come from a colony that was living in the ground underneath the basement slab floor. Although these pests can be a nuisance, they do not sting.