Carpenter Ant Size
Carpenter ants are one of the largest of all ant species. Carpenter ants have polymorphic workers, meaning that ants within a single colony may vary in size. Adult carpenter ants can measure from 6 to 12 mm in length. Males, or winged swarmers, can measure up to 18 mm, while queens grow to 20 mm in length.
A mature colony usually contains around 3,000 adult ants, but some species have been known to contain up to 100,000 ants. Like other ant species, carpenter ants are social insects, and their colonies are composed of different castes. A typical parent colony contains a queen, the queen's brood and workers, both minor and major. The size of worker ants determines their responsibilities. Minor workers are the smallest members of the colony, and their tasks are to take care of the young and forage for food. Major workers are larger and serve as soldiers to defend against predators.
In the United States, there are 24 pest species of carpenter ant. While they may have similar physical characteristics, nesting habits, feeding and destructive behaviors, their colonies contain different carpenter ant sizes. Two factors affect the difference in size between species: the availability of food and the number of workers foraging for food.