Grease ants are one of the smallest species of ants, measuring only 1.5 to 2.2 mm in length. Grease ants are also known as “thief ants” because they nest close to other ant colonies and steal their food and young.
As their name suggests, grease ants prefer greasy foods but will eat almost anything, including meats, nuts, cheeses, peanut butter and sweets. Due to their small size, they can easily fit inside food containers.
Worker grease ants are shiny and measure approximately 1.5 to 2.2 mm in length, with yellow to light or dark brown bodies. The bodies of grease ants tend to curl when they die. They have two nodes, a thorax without spines, small compound eyes, antennae with 10 segments and antennal clubs with two segments. Grease ants are commonly confused with the pharaoh ant, but pharaoh ants have a three-segmented antennal club.
Grease ant infestation is most common in the summer, when they forage indoors for food. When a colony of grease ants identifies a reliable food source within a kitchen, their infestation can be persistent. Grease ant nests can be difficult to locate. They are typically found in rotting wood and soil, but grease ants can also nest indoors in walls or cabinet crevices, baseboards, under countertops and in other hidden areas.
If a group of foraging ants is found inside your home, it is possible to follow their trail to locate the nest. However, due to the extremely small size of the grease ant, this is not always possible, and the most effective way to halt an infestation is to contact a local pest control professional.