Many kinds of ants live in highly organized colonies in the soil, under rocks, and in tree cavities. Most types don’t eat plants, but instead cause trouble by driving away creatures that prey on or parasitize sap-feeding pests such as aphids, whiteflies, mealybugs, and soft scales. All these pests excrete honeydew, a sugary sap ants like to eat. A column of ants marching up and down a tree trunk usually indicates an infestation by sap feeders.
Fire ants, a major pest in the South, do feed on plants—as well as on other insects. They build hard mounds up to 2 feet tall and inflict painful stings when disturbed.
Don’t confuse ants with termites; ants are distinguished by their narrow waists and elbowed antennae.
Target: Honeydew (most species), fruits and vegetables (fire ants).
Damage: Most ants don’t damage plants directly. Fire ants are an exception; they devour plants and spoil gardens with their mounds. Nuisance pest in the home.
Life cycle: Winged males and females hatch about once a year. After mating, the males die and the females lose their wings. Each female establishes a nest, laying large numbers of eggs that hatch into workers. Colonies overwinter in soil or garden debris.