An ant mill is a phenomenon where separated army ants lose their pheromone trail and follow each other in a spinning circle until exhaustion, a side effect of their self-organizing colony structure. William Beebe first documented this, observing a mill with a 1,200-foot circumference where each ant took 2.5 hours to complete one loop.
EcoSmart natural plant-based insect killer from Home Depot uses clove and thyme oils to remove ants from lawns in an eco-friendly way. The 10-pound bag covers up to 5,000 square feet, is safe for children and pets when used as directed, and has a 4-star average rating, though heavy rain may require reapplication.