Cornfield Ant

The cornfield ant is a small light to medium brown Lasius worker 2–3 mm long with a single-node waist and no sting. Colonies are typically single-queened but extremely dense — hundreds of nests can occupy a single lawn or fairway — and each produces the small crater of excavated soil that is the species' signature. Large synchronised mating flights occur on humid late-summer afternoons, when clouds of alates emerge and are a common source of panicked service calls.

Workers are day- and evening-active and forage almost entirely for honeydew, tending root-feeding aphids and corn-root aphids underground and moving them between host plants — a genuine agricultural relationship that gives the species its name. Above ground they scavenge insects and sweets and will trail indoors to kitchens. They neither bite meaningfully nor sting, and cause no structural damage; complaints centre on soil craters on turf, displaced sand in pavement joints, indoor trailing, and swarming alates.