Practical information to identify and manage non-native, invasive plants and animalsThe Quiet Invasion:
A Guide to Invasive Species of the Galveston Bay Area
Formosan subterranean termite|
Human HealthThese species pose no known human health impacts.
Prohibited ListsAs of 2010, this species is not prohibited in Texas.
Introduction PathwaysThis species can be transported in shipments of cargo including landscape timbers, mulch, and potted plants (Raloff 2003). Introductions are tied to trade routes extending around the world from Asia to the U.S. (Austin et al. 2006). The species was first reported in the U.S. in the 1960s in Texas, Louisiana, and South Carolina (Su and Scheffrahn 2010).
Geographic DistributionThis species is found in all five counties of the Lower Galveston Bay watershed (TAMU 2008) as well as in Alabama, California (an isolated infestation), Florida, Georgia, Hawaii, Louisiana, Mississippi, North and South Carolina, and Tennessee (Su and Scheffrahn 2010).
Specific Primary HabitatsThis termite is found in forests and urban areas. As the name in implies, this species exists in large, underground populations that share interconnected galleries, tunnels and foraging tubes (Su and Scheffrahn 2010). Underground galleries of this species may extend up to 100 meters (King and Spink 1969; Su and Scheffrahn 1988; Su and Lee 2008).
Ecological, Economic, or Social ImpactColonies are large (over 70,000 alates or winged individuals) (Su and Scheffrahn 2010). Because of this, damage to structures can be greater than that caused by native termites. Commonly infested structures include boats and ships, homes and other buildings, as well as live and dead trees (ISSG 2006b). Infestations by this species are recognized by a thin, blistered or peeled wood surface that is hollow beneath. Foraging tubes 0.25 to 0.5 inches in diameter may be found connecting soil tubes and the infested structure (Su and Scheffrahn 2010). Nest material (known as carton) resembles cardboard or papier-mache and may be found in spaces between walls in infested structures (Su and Scheffrahn 2010). This species is very aggressive and can out-compete native species of termites. C. formosanus is currently believed to be one of the most destructive insect pests in the U.S. Pimentel et al. (2005) estimated that this species results in losses and control costs of $1 billion annually in the U.S. Management of this species includes prevention, soil treatment, and baits.
Physical DescriptionColonies contain three types of individuals: reproductives (the king, queen, alates, and nymphs) soldiers, and workers. Of these, alates and soldiers are the easiest to identify. Alates are yellowish-brown and approximately 0.5 inches in length. Alates may occur in swarms and are attracted to light sources (Su and Scheffrahn 2010). Soldiers are numerous (up to 10-15% of the population) and have an orange-brown, oval-shaped head (Su and Scheffrahn 2010). They have dark-colored mandibles that cross near the tips. When disturbed, soldiers may attack and secrete a sticky, white substance from an opening on the head.
Reproduction CharacteristicsFemale alates undertake a brief flight to new nesting sites where they are joined by males. A male and female choose a moist crevice where they create a royal chamber and lay 15-30 eggs. The eggs hatch in approximately 2 weeks (Su and Scheffrahn 2010). Larvae are fed by the king and queen. The first brood matures and becomes caretaker to the next group of eggs laid by the king and queen. The cycle eventually results in three types of individuals. Reproductives are responsible for reproduction. Soldiers defend the colony against enemies and predators. Workers maintain the nest, tend to the eggs, and feed the larvae, reproductives, and soldiers.
FeedingThe Formosan termite feeds on wood and other cellulose-containing materials such as paper and cardboard. They are known to chew through foam insulation boards, thin lead and copper sheeting, plaster, asphalt, and some plastics (ISSG 2006b).
ControlSince early detection is key to preventing the spread and establishment of this species, regional/local monitoring or surveillance is essential. Colonies often invade building structures from the ground. Therefore, wood to ground contact can increase the risk of infestation. Formosan termite infestations are difficult to control. Professional pest services may use a combination of termite baits and/or placement of a chemical barrier between the building structure and termite colony.
This species belongs to the following lists:
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Page Updated/Reviewed: 08/31/2010 1:46 PM |