Field Ants (Formica spp.)
Description of Workers: Large ants, (3/8-inch) often confused with Carpenter ants. Wide variation in color: black, brown, tan, reddish, or red and black in color. Thorax is bumpy in appearance. Key distinguishing feature: The presence of 3 ocelli on head (ocelli are simple eyes on the front of the head between the ant's compound eyes - see photograph above).
Field ants are common around structures, but are not often found inside. These ants are soil nesters and may construct mounds in open fields. In lawns, these nests have a low profile. rarely reaching above the top of the grass. They also nest under objects like rocks, landscape timbers and firewood piles. Displaced soil is often evident. Items such as stones, logs, and bricks should be overturned and inspected for colonies underneath.
Management includes treating colonies by drenching mounds thoroughly with a sufficient amount of a diluted, appropriately labeled insecticide using a sprayer to insure complete saturation throughout the colony which may be 8-12-inches or more in diameter. It may be necessary to lift objects on the ground to treat the colony underneath. The colony may also be controlled with granular bait products, although these products may not readily be available over-the counter.
View & Print Free Ant Identification Keys
This resource was updated November 2015 by Soni Cochran, Extension Associate
Credits: Ant illustrations were developed by Vicki Jedlicka, Nebraska Extension in Lancaster County
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