The Formosan subterranean termite is one of the most destructive termite species in the world today. It was first discovered in the mainland of the USA in 1957 in Charleston, South Carolina and has since spread to many other areas of the United States.
Formosan termites usually swarm in the late Spring, during warm and humid evenings. Swarms are quite large with up to tens of thousands of alates. The swarmers are attracted to lights and are often found around windows, light fixtures, windowsills, and spider webs in lighted areas. Other differences from native subterranean termites are the size of mature colonies. It is generally believed that their colony strength can reach as high as five million individuals compared with about one million termites in native subterranean termite colonies. They frequently create nests called carton, made primarily of chewed wood and their own saliva, to establish colonies above the ground without contact to soil.