Termites are wood-destroying insects in the order Blattodea that cause an estimated $5 billion in structural damage to US homes every year, and most of that damage goes undetected until it is already significant. Unlike ants and other visible household pests, termites operate inside wood, inside soil, and inside wall voids where they are rarely seen directly. What homeowners find instead are the secondary signs: mud tubes running up a foundation wall, small piles of hexagonal frass near a baseboard, discarded wings on a windowsill after a spring swarm, or wood that sounds hollow when tapped. Acting on those signs quickly is what separates a manageable DIY treatment from a structural repair bill.
What Termites Are and How They Live
Termites are eusocial insects that live in colonies organized around a reproductive queen, a king, non-reproductive worker termites, and soldier termites whose role is to defend the colony against predators. The workers do all the feeding damage: they are the caste responsible for chewing through cellulose, the structural component of wood, paper, cardboard, and other plant-based materials. A mature subterranean termite colony can contain several hundred thousand to more than a million workers, all feeding continuously. Drywood termite colonies are much smaller, typically numbering in the thousands, but they establish directly inside the wood they consume so there is no soil colony to intercept with a soil treatment.
The termite life cycle moves through egg, nymph, and adult stages. At certain times of year, colonies produce winged reproductives called alates. These alates swarm, mate, shed their wings, and attempt to found new colonies. A termite swarm near or inside a structure is one of the clearest signals that an established colony is nearby. Correctly identifying a swarm as termites rather than flying ants is a critical first step, and the differences in wing shape, waist shape, and antenna form are reliable identifiers covered in the guide to telling termites apart from flying ants.
The Two Species Groups That Matter Most for US Homeowners
The vast majority of termite damage in the United States is caused by two distinct groups: subterranean termites and drywood termites. They differ in where they nest, how they forage, what signs they leave behind, and critically, what treatment approach works against them. Both are also widely known by another name: anyone searching for white ants is almost always looking at one of these two termite groups, since white ants are termites rather than a kind of ant.
Subterranean termites nest in the soil and travel up into wood through mud tubes they build to maintain humidity. They require contact with soil moisture to survive, which is why their prevention is closely tied to eliminating wood-to-soil contact, managing moisture under structures, and applying liquid termiticide or bait systems at the soil level. The most widespread subterranean species in the US belong to the genus Reticulitermes, present in every state except Alaska. The Formosan subterranean termite (Coptotermes formosanus) is an invasive species concentrated in the Gulf Coast and Southeast with a significantly larger colony size and more aggressive foraging behavior. The full biology, identification, and treatment framework for subterranean termites is covered in the subterranean termite guide.
Drywood termites nest inside wood with no soil contact required. They are primarily found in coastal and southern states from California through the Gulf Coast and up the Atlantic seaboard to Virginia. Their presence is often detected through frass, the small hexagonal fecal pellets they push out of kickout holes in wood surfaces. Because their colony lives inside the wood rather than in the soil, soil treatments have no effect on them. Treatment requires either localized injection of termite foam or boron-based products into the wood, or whole-structure fumigation for severe infestations. The biology, signs, and DIY treatment options for drywood termites are covered in the drywood termite guide.
How to Recognize a Termite Problem
Knowing what to look for is the first practical step, and there are several reliable physical signs that indicate termite activity. Mud tubes on foundation walls, piers, or joists are the most definitive sign of subterranean termite activity. Frass near wood surfaces or in small piles below furniture and trim indicates drywood termites. Hollow-sounding wood when tapped, blistered or darkened wood surfaces, sagging floors or ceiling sections, and loose tiles caused by moisture introduced by termites under flooring are all structural damage indicators. Discarded wings on windowsills or near doors after a warm spring day indicate a recent swarm. A detailed walkthrough of each sign and where to look for it is in the signs of termite infestation guide.
DIY Treatment Options
Several effective DIY termite treatments are available to homeowners, and product choice depends on species, infestation location, and how accessible the affected area is. Liquid termiticides applied as a continuous soil barrier around the foundation are the primary treatment for subterranean termites. Products containing fipronil (Termidor SC) or bifenthrin are the most widely used active ingredients for this application. Termite bait stations installed in the soil around the perimeter offer an alternative approach: they intercept foraging workers, who carry slow-acting bait back to the colony, eventually eliminating it. For drywood termites in accessible wood, termite foam products and boron-based wood treatments are the practical DIY options.
Product-specific guidance, application rates, and safety information are covered in the hub’s three dedicated treatment pages: the best termiticide for DIY soil treatment, the best termite bait stations for homeowners, and the best termite foam for drywood and void treatment. For homeowners who prefer lower-toxicity options, the guide to natural termite remedies separates the borate, nematode, and orange oil methods that genuinely work from the household remedies that do not.
When to Call a Professional Instead
DIY termite treatment is effective for many infestations, but there are situations where professional treatment is the more practical path. Whole-structure tent fumigation with sulfuryl fluoride, required for severe or widespread drywood infestations, is not available as a DIY option and requires a licensed applicator. Formosan subterranean termite infestations, given the colony sizes involved, often exceed what a homeowner soil treatment can control reliably. Any situation involving active structural damage to load-bearing members warrants a professional inspection before treatment, to assess repair requirements alongside control. The how to get rid of termites overview covers the decision criteria between DIY and professional treatment in detail, and the cost to treat termites guide compares the price of each DIY and professional method so the decision accounts for budget as well as severity.
Prevention Starts with Moisture and Wood Contact
The most effective long-term termite prevention strategy is structural: eliminate the conditions that make a property attractive to termites in the first place. Subterranean termites require soil moisture and are drawn to wood-to-soil contact points such as untreated fence posts, deck boards sitting on grade, firewood stored against a foundation, and mulch banked against siding. Keeping mulch pulled back from the foundation by at least six inches, ensuring gutters and downspouts direct water away from the structure, fixing plumbing leaks under slabs and in crawl spaces, and maintaining adequate ventilation in crawl spaces all reduce the moisture conditions subterranean termites need to thrive. The complete set of preventive measures, the treatments worth applying proactively, and how often to inspect and treat are detailed in the termite prevention guide. The integrated pest management framework that connects moisture management, prevention, and treatment decisions is covered in the integrated pest management guide.