What Are Termite Mud Tubes?

During a termite inspection of your home, pest control professionals will look for signs of termites in and around your property to determine whether or not there is a current infestation. Some of these signs of termites include wood damage, “shelving,” winged termite swarmers, termite fecal matter (known as frass), and more. Some of the most telling and significant indicators of a termite infestation are mud tubes.

If you see what looks like veins of mud running up the walls or even across the ceiling of your home, it’s likely you have an active or recently active termite infestation. But what are mud tubes, and what are they for?

Below, we’ll explain what mud tubes are, what purposes they serve, and what to do if you see these brown tunnels creeping up your walls.

How Termites Build Mud Tubes

Termite mud tubes, also known as termite shelter tubes, are made of soil, wood particles, termite saliva, and other organic materials.

Construction of mud tubes usually begins when subterranean termites — the most common type of termites that build these tubes — locate a food source above ground. They create the tubes from the soil or other available materials, using their saliva as a binding agent. Termite mud tubes are typically about the width of a pencil, and their length can vary depending on the distance between the termite colony and the food source.

Mud tubes typically run along surfaces, like walls, ceilings, subfloors, joists, or along a home’s foundation, but termites can build mud tubes anywhere. Advanced mud tubes can even span open air, especially in basements and crawl spaces, as termite workers build stalagmite-style pillars of mud tubes called “drop tubes” to connect dirt basement floors to wood structures above.

Why Termites Need Mud Tubes

Termites build mud tubes as a means of protecting themselves from predators and the elements. The tubes serve as covered passageways that shield the termites from light, temperature extremes, rain, and wind.

Termite tubes also protect workers from numerous predators. Being small, defenseless, and found in large colonies, termites make for an easy meal for many predators in the United States. Termites are eaten by (and can attract) other insects — including spiders, wasps, centipedes, cockroaches, crickets, and dragonflies — as well as birds and some small mammals.

Mud tubes also help termites navigate over non-wooden surfaces, such as concrete or brick, on their way to consume cellulose found in human homes in the form of wood, paper, carpet, fabric, cardboard, and more. Mud tubes are usually broken down into three different categories.