Large Yellow Ant – Citronella Ant

Biology of the Large Yellow Ant

Large yellow ants average approximately ¼ of an inch long. As their name suggests, they are a yellow color. Large yellow ants are also called citronella ants: for the lemony scent they produce when crushed. Citronella ants are not often seen outside their nests during the day as they primarily forage at night. You may encounter them when they swarm (mate), during which the reproductive queens and drones will establish new nests. Large yellow ants will in most cases not harm any structure, preferring decayed wood and other insects for food.

Large Yellow Ant

Habitat and range of Large Yellow Ant

The large yellow ant ranges throughout the western United States. This ant can often be found nesting in soil under rocks and stumps or logs. They are usually found around houses under a concrete slab where their nest is indicated by a large buildup or dirt in the expansion cracks of the cement.

Large Yellow Ants Tending to an Egg Pile

Prevention of Large Yellow Ants

Large Yellow Ant colonies can be dissuaded from your property by cleaning the yard of fallen debris, such as leaves, and keeping areas tidy. As this ant takes a liking to stumps, logs and stones, it’s best to keep any of these items several feet from the house to discourage the ant from going into your house. If there is nothing for the ant to find in your house they are even less likely to enter and look for food. So keep your food items in secure plastic containers.

Professional Control of Large Yellow Ants

Large Yellow Ants could be incredibly difficult to treat due to their nests generally being below paving slabs. It had once been recommended to find a pest control technician trained in handling termites, as it was often necessary to drill through the paving slab. Once the mound was exposed you could drench the mound with an insecticide.

When Citronella ants swarm, a vacuum may be utilized to clean up these ants from the inside of a house. Bait based insecticide while affective for a wide range of ants will not work for this species of ant, and is not a viable control.

It is our opinion that new non-repellent baits are a viable option that would eliminate the need to drill through slab, as the delayed kill factor allows the ants to infect other ants in the nest before death.