Subterranean termites live in soil and build mud tubes to access wood, making them the more destructive of the two. Drywood termites nest inside wood and need no soil contact. Correctly identifying which species you’re dealing with is essential, as treatment methods differ significantly—and misidentification can make an infestation worse.

Every year, termites cause an estimated $6.8 billion in property damage across the United States—more than fires, floods, and storms combined, according to the National Pest Management Association (NPMA). Yet despite how common termite infestations are, most homeowners can’t tell one species from another. That gap in knowledge is costly.

Two termite species dominate most residential pest concerns in the U.S.: subterranean termites and drywood termites. They look similar at a glance, but they behave very differently, live in different environments, and require completely different treatment approaches. Confuse one for the other, and you risk applying the wrong solution—wasting time and money while the colony continues to grow.

This guide breaks down the key differences between subterranean and drywood termites, explains what to look for in your home, and clarifies why correct identification is a job best left to a licensed pest control professional.

What Are Subterranean Termites?

Subterranean termites are the most widespread and destructive termite species in North America. As their name suggests, they live underground—specifically in moist soil—and travel to their food source (your home) through a network of tunnels.

How do subterranean termites behave?

These termites rely on moisture to survive. Without consistent contact with damp soil, a colony cannot sustain itself. To bridge the gap between their underground colony and the wood they feed on, subterranean termites construct mud tubes—pencil-width tunnels made from soil, wood debris, and saliva—along foundation walls, pipes, and other surfaces.

Subterranean colonies are enormous. A mature colony can contain anywhere from 60,000 to over one million workers, which explains why these termites are responsible for roughly 95% of all termite damage in the U.S., according to the NPMA.

What signs indicate a subterranean termite infestation?

• Mud tubes along the foundation, basement walls, or crawl spaces
• Hollow-sounding wood when tapped
• Darkening or blistering wood surfaces, particularly near the ground floor
• Swarmer termites (winged reproductives) emerging from soil in spring

What Are Drywood Termites?

Drywood termites operate very differently. Rather than nesting in the soil, they establish colonies entirely within dry wood—no ground contact required. This makes them harder to detect and, in some ways, more insidious.

How do drywood termites behave?

Drywood termites extract moisture directly from the wood they consume, which means they can thrive in dry conditions where subterranean termites cannot. They infest structural lumber, hardwood floors, furniture, and wooden frames—essentially any dry wood they can access.

Their colonies are significantly smaller, typically ranging from a few hundred to around 2,500 individuals. While they cause damage more slowly than subterranean termites, the fact that they can attack virtually any wooden surface—including furniture and cabinetry—makes them a serious concern, especially in warmer coastal states like California, Florida, and Hawaii.

What signs indicate a drywood termite infestation?

• Frass (termite droppings): Small, hexagonal pellets that resemble sawdust or sand, found near infested wood
• Kick-out holes: Tiny holes in wood surfaces where termites expel frass
• Smooth, clean galleries inside wood: Unlike subterranean termites, drywood termites don’t pack their tunnels with soil
• Swarmers emerging from wood structures, often in late summer or fall

Subterranean vs. Drywood Termites: Side-by-Side Comparison

Feature	Subterranean Termites	Drywood Termites
Nesting location	Underground, in moist soil	Inside dry wood (no soil needed)
Moisture requirement	High — need constant soil moisture	Low — extract moisture from wood
Colony size	60,000–1,000,000+ workers	500–2,500 workers
Key identifier	Mud tubes along foundations	Frass pellets near wood surfaces
Wood damage pattern	Follow grain; soil-packed tunnels	Cut across grain; clean, smooth galleries
Geographic range	Found across all U.S. states	Concentrated in warm coastal states
Swarm season	Spring (typically March–May)	Late summer to fall
Destruction rate	Fast — large colony, rapid damage	Slower — smaller colony
Common treatment	Liquid soil termiticides, bait systems	Fumigation, localized wood treatments

How Do You Tell Them Apart by Damage Patterns?

Wood damage is one of the clearest diagnostic clues—but you have to know what you’re looking for.

Subterranean termites eat wood along the grain, leaving long, hollow chambers packed with soil and debris. Run your hand along a piece of damaged wood, and it will feel rough and uneven. You might also notice a muddy, earthy residue inside the tunnels.

Drywood termite damage looks cleaner. These termites cut across the wood grain, creating smooth, open galleries with no soil inside. The wood may still look intact from the outside, but tapping it reveals a hollow core. The frass they leave behind—neatly expelled through kick-out holes—is one of the most reliable identifiers: look for tiny, six-sided pellets that can accumulate in small piles beneath infested furniture or framing.

Why Correct Termite Identification Demands Professional Expertise

Here’s the problem with DIY termite identification: both species can be present in the same property, and the signs of an infestation aren’t always obvious until structural damage is already significant.

Misidentification carries real consequences. Treating a drywood termite infestation with a soil-applied termiticide does nothing to eliminate the colony living inside your walls. Conversely, applying a localized wood treatment to what is actually a subterranean infestation—one drawing workers from a large underground colony—will fail to address the source.

Licensed pest control professionals use a combination of visual inspections, moisture meters, acoustic detection tools, and in some cases, borescope cameras to accurately determine which species is present, how extensive the infestation is, and where the colony is located. This diagnostic process directly informs the treatment plan.

The American Subterranean Termite treatment, for example, involves creating a continuous liquid barrier in the soil around the foundation—a process that requires professional-grade equipment and licensing to apply safely. Drywood termite fumigation (tenting) demands that the entire structure be sealed and filled with sulfuryl fluoride gas, a process that is strictly regulated and cannot be performed without a licensed fumigation certificate.

There’s also the issue of structural assessment. A professional won’t just identify the termite species—they’ll evaluate how much damage has already occurred and advise on whether structural repairs are needed alongside treatment.

When Should You Call a Pest Control Professional?

Don’t wait for visible damage. Termites are cryptic pests; by the time you notice hollow wood or frass accumulation, the colony has likely been active for months or even years.

Contact a licensed pest control professional if you observe:

• Any of the warning signs listed above for either species
• Discarded wings near windows, doors, or light sources (a sign swarmers have entered)
• Wood that sounds hollow when knocked
• Unexplained cracks in painted wood surfaces
• Your neighbor has recently treated for termites (colonies can migrate)

Most reputable pest control companies offer free or low-cost inspections. Given that the average cost of termite damage repair in the U.S. runs between $3,000 and $8,000, according to HomeAdvisor, an inspection is a modest investment by comparison.

Protect Your Property Before Termites Do the Math

Subterranean and drywood termites share one thing in common: they work quietly, persistently, and at your expense. The distinction between the two isn’t academic—it determines which treatment will actually work, how quickly the problem can be resolved, and how much structural damage you may be facing.

Knowing the signs is a useful starting point. But accurate identification, treatment selection, and damage assessment require the training and tools that only a licensed pest control professional can provide. If you suspect termite activity in your home, don’t guess. Get a professional inspection, get the right diagnosis, and get ahead of the problem before the colony does.

Frequently Asked Questions

What is the main difference between subterranean and drywood termites?

Subterranean termites nest in moist soil and must maintain ground contact to survive, traveling to wood via mud tubes. Drywood termites nest entirely within dry wood, need no soil contact, and are identified by their hexagonal frass pellets. The distinction matters because each species requires a different treatment method.

Which termite species causes more damage—subterranean or drywood?

Subterranean termites cause significantly more damage overall. Their colonies can exceed one million workers, and they are responsible for approximately 95% of termite-related property damage in the United States, according to the NPMA. Drywood termite colonies are much smaller but can still cause serious structural and cosmetic damage over time.

Can you have both subterranean and drywood termites in the same home?

Yes. In warmer states like California, Florida, and Texas, it is possible for a single structure to harbor both species simultaneously. This is one reason professional inspection is critical—a homeowner treating for one species may unknowingly leave the other untreated.

How do pest control professionals treat subterranean termites vs. drywood termites?

Subterranean termites are typically treated with liquid termiticides applied to the soil around the foundation, or with bait systems designed to eliminate the underground colony. Drywood termites are most commonly treated with whole-structure fumigation (tenting) or localized heat and wood treatments. The correct approach depends on the species, colony size, and extent of the infestation.

How long does it take to notice a termite infestation?

Termite colonies can remain undetected for months to years. Subterranean termite colonies may take three to five years to reach a size where damage becomes visible. Drywood termite infestations typically develop more slowly due to smaller colony sizes, but the absence of visible signs doesn’t mean the colony is inactive.

Is DIY termite treatment effective?

Over-the-counter termite products can suppress minor surface activity but rarely eliminate an established colony. Both subterranean and drywood termite treatments require professional-grade products, licensed application methods, and structural access that consumer products cannot replicate. For established infestations, professional treatment is strongly recommended.

Tags: Get rid of termites, Subterranean vs. Drywood Termites: Know Your Enemy, Termite Control, Termite Inspection