Formosan termite facts & identification

Formosan termites, a particularly aggressive and destructive termite species, pose a significant threat to homeowners across the United States, especially in warm and humid climates. These termites are an invasive species that originated in East Asia but have spread throughout the southern U.S. and Hawaii, causing millions of dollars in damage annually, according to the USDA. In this guide, we’ll explore how to identify Formosan termites, understand their behaviors and habitat, and learn the best methods for prevention and termite control.

Formosan termite identification

What do Formosan termites look like?

Formosan termites are a type of subterranean termite but are larger and more aggressive than native subterranean termite species. They have distinct physical characteristics depending on their role within the colony: workers, soldiers, and reproductives (swarmers or alates).

Worker termites in Formosan colonies are around 1/8 to 1/2 inch long. They are creamy white or pale yellowish in color, wingless, and soft-bodied. They make up the largest portion of the colony and are responsible for foraging, feeding other termites, and maintaining the nest.

The soldiers are more distinctive. They have an elongated, tear-drop-shaped head that is yellowish-brown and equipped with large, powerful mandibles and are about 1/4 to 1/2 inch long. One of their distinguishing features is the small hairs on their heads, which are not present in other subterranean termites. The soldiers defend the colony from predators such as ants.

Swarmers (alates) are the winged termites responsible for reproduction and starting new colonies. They are larger than workers, measuring about 1/2 inch long, with translucent wings covered in fine hairs. The wings are of equal length, and their bodies are pale yellowish-brown. These alates emerge in late spring or early summer to begin new colonies.

Formosan termites can often be mistaken for other subterranean species or even drywood termites, but their larger size and aggressive behaviors set them apart. See our termite identification guide for more details on what different termites look like.

Signs of Formosan termite infestation

Detecting a Formosan termite infestation early is essential to prevent structural damage. Here are the common signs of termites to watch for:

• Mud tubes: Like other subterranean termites, Formosan termites build mud tubes that serve as protective tunnels from their underground nests to the wood they are infesting. These tubes are often found on foundations, walls, and in crawl spaces.
• Swarmers: The appearance of winged termites, or alates, near windows, doors, and light fixtures is a major sign of an infestation. Swarmers are often attracted to light, and their presence indicates a mature colony nearby. After swarming, they shed their wings, leaving piles of wings as evidence of activity.
• Wood damage: Formosan termites are one of the main culprits of termite damage to drywall, wooden beams, floors, and furniture. Unlike drywood termites, they tend to create hollowed-out wood with no external signs, making detection difficult until severe damage has occurred.
• Carton nests: Formosan termites can build carton nests inside walls, attics, or other voids in a house. These nests are made from chewed wood and soil, and they can store moisture, allowing termites to survive even when detached from the ground.
• Termite droppings (frass): Although frass is more commonly associated with drywood termites, subterranean termites like Formosans may leave behind fecal matter if they build nests within the wood structure.
• Termite noise: In some severe infestations, homeowners might hear faint rustling or clicking sounds coming from inside the walls, as termites feed on wood.

Habitat, diet, life cycle & behaviors

Where do Formosan termites live?

Formosan termites are found primarily in warm, humid regions of the southern United States and Hawaii. They thrive in areas with abundant moisture and decaying wood. Unlike drywood termites, Formosan termites need contact with soil to survive, which is why they are classified as a subterranean species. They build large underground nests connected to wood sources through their mud tubes.

Their primary nests are underground, where they build large nests connected to wood sources through their mud tubes but Formosan termites can also establish secondary nests, known as carton nests, in the walls or attics of homes, where they can survive without soil contact due to the moisture retained in the nest.

Diet

Like other termites, Formosan termites feed primarily on cellulose, a substance found in wood and other plant-based materials. They will consume wooden beams, flooring, framing, and drywall paper backing, as well as wooden furniture. Formosan termites often infest living trees and utility poles, which can create significant risks for homeowners and infrastructure.

Life Cycle

Formosan termites follow a life cycle typical of termite species: The queen lays eggs, which hatch into nymphs. These immature termites develop into workers, soldiers, or reproductives, depending on the colony’s needs. Winged reproductives leave the colony to form new colonies, typically in late spring or early summer, and usually after a rain shower. Once the alates find a mate, they shed their wings and start building a new nest. 

Behaviors

Formosan termites tend to swarm in large numbers, especially during humid evenings. Swarming is often the first sign homeowners notice before discovering an infestation. Formosan colonies are much larger than other termite species, with colonies sometimes exceeding several million termites. They are known for consuming wood at a much faster rate than other termite species.

Are Formosan termites dangerous?

While not directly harmful to humans or pets—they do not bite, sting, or carry diseases—Formosan termites pose a risk due to the severe structural damage they can cause to homes and buildings. A single colony of Formosan termites can consume wooden utility poles, beams, and walls at an accelerated rate, leading to extensive and costly repairs. Unlike other termite species, which can take years to cause significant damage, Formosan termites are capable of damaging large portions of a home in a shorter timeframe. Their ability to build carton nests inside walls and infest homes undetected makes them even more dangerous to homeowners.

How to get rid of Formosan termites?

Getting rid of Formosan termites requires a thorough approach, as their large colonies and aggressive nature can make them difficult to control. Here are the most effective termite pest control methods:

• Termite baits: Systems like Sentricon use bait stations placed around the property, which termites find whilst foraging. The termites consume the bait and bring it back to the colony, gradually eliminating the entire colony over time.
• Liquid termiticides: Placed in the soil around the home to create a barrier that prevents termites from entering the house.
• Physical barriers: In new construction, physical barriers can be installed beneath the foundation to help prevent termites from entering.

A termite inspection by a licensed pest control company like Ehrlich is critical to assess the severity of the infestation and recommend the best treatment options.

Formosan termite prevention tips

Preventing Formosan termites starts with eliminating conditions that attract them. Start by reducing moisture around the home: Ensure that your home’s gutters are clean and direct water away from the foundation and repair any leaks in your roof or pipes.

Next, pay attention to the wood around your house and yard. Store firewood at least 20 feet away from your home, and remove any dead trees, stumps, or other wood debris from your yard, as these are prime nesting spots. The National Pest Management Association also recommends maintaining an 18-inch gap between the soil and any wood that forms part of your home, like posts, decking, and siding or wall cladding.

You should also regularly check your home’s foundation, windows, and doors for cracks or gaps and seal them to prevent termites from entering, and schedule regular termite inspections with a pest control professional to detect any early signs of infestation.

Need help with termite pest control?

If you suspect a Formosan termite infestation, it’s essential to act quickly to prevent further damage. Ehrlich’s professional termite control team can provide a free termite inspection and recommend the best treatment options to protect your home. Don’t wait until the damage is irreversible—contact us today for fast, effective solutions.

Formosan termite FAQs