National Formosan Subterranean Termite Program

FAQs > General

What are Formosan subterranean termites?

Formosan subterranean termites are an aggressive non-native termite species. Formosan termites have a horrific appetite and can destroy wood as long as there is a water source nearby. Their diets consist of anything that contains wood fiber (homes, buildings and live trees), crops and plants. Formosan termites can penetrate plaster, plastic and asphalt to get to a new food source. They build large carton nests above or below ground. A highly fertile queen, a long life span, and an extensive foraging system from a central nest site result in much larger colonies than native termite species.

Where are they found? How many states are infested with them?

The termites have been found in Alabama, California, Florida, Georgia, Hawaii, Louisiana, Mississippi, North Carolina, South Carolina, Tennessee, and Texas.

It's believed they were first brought into the United States on military ships carrying supplies from the Pacific after World War II. Their main points of entry were New Orleans and Lake Charles, La.; Galveston and Houston, Texas; and Charleston, S.C.

The pest's destruction is now becoming visible as structural damage, like decaying floors, falling walls and deteriorating trees become more prevalent. The last organo-chlorine termite poison was banned in 1988 because of human health and safety concerns. Their chemical replacements are not as effective or long-lasting, so the pest has had a chance to thrive in the United States.

What's the difference between these termites and other termites?

Formosan termite colonies are much larger than native termite colonies. A mature Formosan termite colony can produce about 2,000 eggs a day. The colony can contain millions of termites. They are a greater problem than native termites because they build more nests above ground, and their colonies contain more individual termites. There are so many members in a colony that they can find ways to penetrate breaches in treated soil. Formosan termites attack live oak, ash, water-bound live bald cypress trees and at least 50 species of plants.

Formosan termites cost consumers more than $1 billion a year, including the cost of repairs. In New Orleans alone, it's estimated that the pest infests as many as 30 percent of the historic live oak trees and can cost individual homeowners several thousand dollars a year in damage and control costs.

How do these termites get into homes and buildings?

They dig underground tunnels in untreated soil and can bypass treated soil to infest homes, buildings and trees. These termites do most of their damage inside walls. They get into walls from the soil, roof or some other hard to detect pathway. All they need is a nearby food and water source to sustain the colony.

How do you control Formosan termites?

New techniques and pesticides are being developed to combat the Formosan subterranean termite. People can help prevent infestations by reducing or eliminating water sources such as leaky pipes; removing any wood and debris in contact with the soil, like wood trellises and roofs; replacing damaged sills and floors, and sealing cracks in concrete and other structural materials. A qualified pest control operator is the best source of advice and treatment.

For more information, contact the Southern Regional Research Center, Agricultural Research Service, USDA, New Orleans, La. 70179. Telephone: (504) 286-4444.