Identification
Western harvester ants are reddish-brown and measure between 1/4 to 1/2 inch in length. They have six legs, elbowed antennae, and a two-segmented petiole. Their mandibles are strong, allowing them to gather and crush seeds. Unlike some ants, they have a painful sting used for defense.
Lifecycle & Reproduction
Western harvester ants undergo complete metamorphosis, progressing through egg, larva, pupa, and adult stages. Queens can lay hundreds of eggs, which hatch in about 2 to 4 weeks. Worker ants live for several months, while queens can survive for years. Colonies expand steadily, with mating flights occurring in summer.
Habits, Diet & Behavior
Western harvester ants primarily feed on seeds, which they store in underground chambers. They forage in long trails and clear vegetation around their nests, creating large, bare soil patches. Unlike many ant species, they do not scavenge human food.
Where You’ll Find Them / Typical Locations
Western harvester ants nest in open, dry environments, commonly found:
- Grasslands, fields, and prairies
- Near sidewalks, driveways, and roadsides
- In sandy or loose soil areas
- Around agricultural lands and pastures
- Near homes with sparse vegetation
Threats & Danger
Western harvester ants have a potent sting that causes pain and swelling. Their large colonies can damage plant roots and disturb soil. Their aggressive nature makes them a concern for humans and animals, especially in outdoor spaces.
Prevention
- Remove food sources by keeping vegetation trimmed
- Seal cracks and gaps around buildings to prevent entry
- Avoid leaving bare soil patches where they can nest
- Use baiting systems to target colonies effectively
- Maintain well-irrigated lawns to discourage nesting
Signs of Infestation
- Large, cleared patches of soil near nesting sites
- Trails of reddish-brown ants gathering seeds
- Increased ant activity in dry, open spaces
- Presence of multiple entrance holes leading underground
- Painful stings from disturbed colonies
How to Get Rid of It
- Use granular bait formulated for harvester ants
- Apply non-repellent insecticides to entry points and trails
- Drench nests with insecticidal solutions for direct control
- Introduce natural predators such as ant-eating beetles
- Contact professional pest control for widespread infestations