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How to Manage Pests

Key to Identifying Common Household Ants

Argentine ant: Colony propagation

New colonies are established in the spring and summer and are propagated by budding, where one or more newly mated queens crawl out of an established colony with a group of workers. Winged reproductive forms are produced in the spring, but there are no flights as observed for other ant species. Argentine ants mate inside the nest. Spring nests are found in open ground. In warmer weather, ants may move nests to more hidden areas such as under houses. The nests in the summer are very shallow, reaching only 1 to 2 inches below the soil surface. There are multiple queens per colony. Queens are very mobile and can quickly move to new locations if conditions are unfavorable. In the fall, colonies merge into larger colonies with hundreds of queens by the process of budding; they remain large throughout the winter. During the winter months, ants may move indoors.