Several destructive termite species are known for infesting homes and buildings throughout Louisiana. Common termite pest species in the state include eastern subterranean termites, arid-land subterranean termites, and non-native powderpost drywood termites. The first species listed above causes more structural damage to homes annually than any other wood-infesting insect pest species on the continent. However, in Louisiana, the eastern subterranean termite is second to the invasive Formosan subterranean termite in terms of annual infestation rates and wood damage inflicted to homes.

Non-native Formosan subterranean termites (FST) are similar to other subterranean termite species when it comes to habitat and food preference. However, unlike most subterranean termite species, FST can establish aerial infestations in trees and other elevated wood sources. Native subterranean termite species in the US inhabit colonies located solely within ground-soil. Therefore, native subterranean termite infestations are largely limited to substructural wood components located around foundations and in crawl spaces where workers can make quick return trips to soil to hydrate as needed.

Obviously, workers in aerial FST nests cannot travel to the ground-soil to hydrate; instead, workers build enclosed nests that are designed to retain moisture. These nests are known as “carton” nests, and they are made from a mixture of soil, saliva, fecal matter, and chewed wood that hardens as it dries. Carton nests are also constructed in the ground-soil, and aerial carton nests can only be established around structural wood components that are sufficiently moist. Aerial nests are often located in wall voids and floor voids where moisture levels are consistently high.

While all termite species see reproductive swarmers (alates) establish colonies in new areas during certain times of year, the FST is the only subterranean termite species in the US that swarm around artificial lights in massive numbers during the nighttime hours. The presence of termite alates around street lights and porch lights indicate that colonies are nearby, and alates congregating around indoor lights could mean that an infestation has been established within a home.

The habitat range of FST in Louisiana has historically been limited to southern areas, particularly New Orleans, but today, these destructive insect pests have spread throughout the state. FST population numbers in Louisiana continue to grow, as the last decade has seen the number of FST colonies in the state increase by 3,000 percent. FST alates swarm each year during May and June in Louisiana.

Have you ever visually spotted an FST carton nest?