What a Termite Nest Looks Like Underground

A subterranean termite nest has no outer shell, and it isn't one object you could dig up. It is a set of small chambers, sometimes called galleries, linked by narrow tunnels through the soil. The chambers can sit 4 to 18 inches deep or more. Foraging workers spend much of their time in the top 4 to 6 inches of soil, where dead wood falls and rots. The colony often centers on a buried food source, like an old stump or log, and it can feed at spots more than 200 feet apart.

Workers build the tunnels from soil and bits of wood held together with saliva and feces. Inside, a queen lays eggs, workers feed the colony, and soldiers with large brown heads guard the tunnels against ants. Texas A&M says a native subterranean colony matures in 3 to 5 years and usually holds about 250,000 workers. Several colonies can live near each other and feed on the same house.

Where Do Termites Nest Around a House?

Subterranean termites nest where they find moist soil and wood close together. Texas A&M points to wood left in the ground, such as stumps, scrap lumber and the form stakes builders leave behind. From there, the workers reach the house through wood that touches the soil, or by building tubes over and through cracks in the foundation.

DFW yards add their own risks. Our clay soil shrinks in dry weather, and some homeowners water along the foundation in summer to keep the slab from cracking. That same watering can draw foraging termites too, Texas A&M AgriLife warns. Dripping air conditioner lines and clogged gutters keep the soil damp in the same spots. Flower beds piled above the slab line also hide the tubes termites build up the wall.

Sometimes termites nest above ground. When a leak keeps wood wet, native subterranean termites can live away from the soil for long stretches. Formosan termites go further. They build carton nests from chewed wood, soil, saliva and feces, and they can tuck those nests into wall voids. Texas A&M AgriLife's guide to Formosan termites reports them in all of the state's major metro areas. It names recycled railroad ties and landscape timbers as the likely main way they spread.

Termite Nest Types Compared

The table below compares the four kinds of termite nest people search for, and which ones turn up around DFW homes.

Nest type Built by Where it is Found in DFW?
Underground colony Native subterranean termites Chambers and tunnels in the soil, often away from the house Yes, the most common
Carton nest Formosan termites In the soil, or in a wall void that stays moist Possible, reported in every major Texas metro
Galleries inside wood Drywood termites Inside dry wood above the ground Rare, they cluster along the Gulf Coast
Mound Tropical species Open ground in Africa, Australia and other hot regions No

What You See Instead of a Nest

Since the nest stays hidden, the colony shows itself through what the workers build. Mud tubes are the clearest sign. They run about the width of a pencil up slab edges, piers and plumbing lines, and they let workers cross concrete to reach wood without drying out. Texas A&M advises breaking a tube open to check for live termites, which look creamy white and measure 1/4 to 3/8 inch.

Damaged wood is the second clue. Subterranean termites eat along the grain and leave galleries lined with mud, often behind a surface that still looks normal. Inside the house, small mud tubes can poke out of drywall, trim or ceilings like tiny tan stalks. In spring, swarms of winged termites and piles of shed wings near windows tell you a mature colony is close.

What you won't find in DFW is a pile of pellet droppings. Those come from drywood termites. Subterranean termites keep their waste inside the tunnels.

What to Do About a Termite Nest

Don't dig for the nest or spray the mud tubes. A shovel can't reach a colony spread through the yard. Spraying a tube only kills the workers in that tube, and the queen keeps the colony going underground.

Treatment works on the colony instead. Bait stations set in the soil let workers carry a slow-acting bait back to the nest, so the colony itself dies off. Forterra uses Sentricon bait stations for subterranean termites because the bait reaches the colony without trenching or drilling through the slab. Liquid soil treatments are the other common option.

The damage builds slowly, which leaves room to book an inspection and weigh the options calmly. A free termite inspection finds out whether that colony is still feeding and where it reaches the house.

Termite Nest FAQ

How do I get rid of a termite nest?

You treat the colony rather than the nest, because you can't find or dig out an underground nest. Bait stations and soil treatments both reach the termites that travel between the nest and your house. Texas A&M notes that soil treatments need specialized drills, injectors and pumps, so it recommends leaving them to licensed professionals.

Can termites build a nest inside a wall?

Yes, when the wall stays wet. Formosan termites can build a carton nest inside a moist wall void, and Texas A&M notes those nests usually stay hidden until someone opens the wall. Native subterranean termites can also set up a secondary colony near a long-running leak.

Do termites build nests in trees?

Not the hanging nests you see in tropical photos. In Texas, Formosan termites can attack living trees, and subterranean termites sometimes tunnel into the dead heartwood of a living tree. A hollow tree near the house is worth pointing out during an inspection.

Do termites ever go away on their own?

No. A colony keeps feeding as long as it has wood and moisture, and the queen keeps laying eggs, so the colony grows over time. Fixing leaks and pulling wood away from the soil make a house less inviting, but they don't remove a colony that's already feeding.