Subterranean vs Drywood Termites in Los Angeles: Treatment Differences Explained

I. Introduction

Termite infestations represent one of the most pressing concerns for Los Angeles homeowners. Two species dominate the region: subterranean termites and drywood termites. Each species can compromise wooden structures, but they do so in very different ways. Subterranean termites are tied to the soil, requiring constant access to moisture to survive. They build large underground colonies and invade homes through mud tubes that provide safe passage. Drywood termites, by contrast, are not reliant on soil. They establish their colonies directly inside wood, extracting the moisture they need from timber itself. This independence allows them to infest attics, furniture, and framing without leaving obvious signs.

Because of these differences, treatment methods must be tailored to each species. What works against subterranean colonies often fails to reach drywood infestations, and vice versa. This distinction makes accurate identification a critical first step in any termite control strategy. A misdiagnosis can result in wasted resources, ineffective treatments, and continued structural deterioration.

Homeowners often underestimate how important it is to understand which species they are dealing with. A subterranean infestation may require treatments that target soil and moisture, while a drywood infestation may call for fumigation or direct wood injections. The costs, timelines, and level of disruption vary depending on the species. By examining the traits of both subterranean and drywood termites, as well as their treatment options, Los Angeles residents can make informed choices that protect their homes and avoid unnecessary expenses.

II. Subterranean Termite Characteristics

Subterranean termites are considered the most destructive termite species in the United States, and Los Angeles is no exception. Their colonies, built underground, can grow into massive populations numbering in the hundreds of thousands or even millions. These termites are highly organized, with castes that divide responsibilities for survival and growth. Unlike other termite species that live exclusively within wood, subterranean termites require soil and moisture. This dependence on water shapes everything about their behavior, from how they forage to where they build their colonies.

One of their most distinctive traits is their ability to construct mud tubes. These structures allow subterranean termites to move between their underground nests and food sources above ground while staying hidden and protected. They use these tubes to maintain the humid conditions they need and to avoid predators such as ants. Their relentless foraging behavior, combined with their ability to travel long distances, makes them extremely effective at finding and exploiting sources of cellulose in homes and businesses.

The Los Angeles climate provides a nearly ideal environment for subterranean termites. Mild winters mean they remain active year-round, while seasonal rains and widespread irrigation offer consistent moisture to sustain colonies. Because they can stay hidden underground for years while consuming wood unseen, infestations often go unnoticed until damage becomes severe. This ability to operate undetected, combined with their vast colony sizes, explains why subterranean termites account for the majority of termite-related damage in the region. Understanding their biology, habitat, and behaviors is essential for selecting the right treatment.

Biology and Colony Structure

Subterranean termites live in colonies that can number from several thousand to more than a million individuals. These colonies have a caste system:

• Workers handle foraging, feeding, and maintaining tunnels.

• Soldiers protect the colony from predators, especially ants.

• Reproductives, including the king, queen, and alates (winged swarmers), ensure colony growth and expansion.
  

Moisture Requirements and Soil Contact Needs

Moisture is essential to the survival of subterranean termites. They rely on humid soil environments to regulate their bodies and prevent dehydration. Their colonies are established underground, and they use soil as a constant source of water. Homes with water leaks, poor drainage, or high soil moisture levels are especially vulnerable.

Foraging Behavior and Mud Tube Construction

Subterranean termites are relentless foragers. Workers travel long distances through the soil, building protective mud tubes to connect their colonies to above-ground food sources. These tubes serve several purposes:

• Protecting termites from predators

• Maintaining the humidity they require

• Allowing them to travel unseen into homes and buildings
  

Seasonal Activity Patterns in Los Angeles

While subterranean termites remain active throughout the year in Los Angeles, swarming events occur most often in spring and occasionally in fall after rain. Swarming is when winged alates leave the nest to mate and start new colonies. Because Los Angeles has a mild climate and many irrigated landscapes, conditions for subterranean activity remain favorable year-round.

Preferred Wood Types and Moisture Levels

Subterranean termites prefer softwoods or damp wood that is in contact with soil. Porch supports, crawl space beams, and basement timbers are common targets. However, when conditions are right, they can attack almost any cellulose-containing material, including hardwoods, cardboard, and even paper products.

Geographic Distribution in Los Angeles County

Subterranean termites are found across Los Angeles County, particularly in areas with older homes or properties where irrigation or poor drainage provides consistent soil moisture. Their ability to remain hidden underground while causing extensive damage makes routine inspections vital.

III. Drywood Termite Characteristics

While subterranean termites dominate in terms of colony size and destruction speed, drywood termites are equally problematic because of how stealthy they are. Unlike their soil-dependent counterparts, drywood termites live entirely within the wood they infest. They do not need external water sources and can survive in dry environments by extracting moisture from the cellulose they eat. This remarkable adaptation makes them well-suited to Los Angeles, where arid conditions are common.

Drywood termites cause damage in a very different way than subterranean termites. Instead of entering from the ground, they establish colonies directly inside wooden structures such as beams, rafters, or furniture. Because they remain concealed inside wood, infestations often go undetected for years. By the time visible signs appear, extensive hollowing may have already occurred. Detecting them requires close attention to small clues like frass (termite droppings) or minor cracks on wooden surfaces.

These termites also swarm differently from subterranean species. Their swarms tend to be smaller, less obvious, and often occur in late summer or early fall. Homeowners may overlook these events, allowing infestations to grow unchecked. Because drywood termites can spread into multiple areas of a structure without relying on soil, infestations can affect attics, roofs, and furniture simultaneously.

For Los Angeles homeowners, drywood termites represent a significant challenge because standard subterranean treatments like soil barriers are ineffective against them. Instead, treatments must target the infested wood directly or saturate entire structures. This makes accurate identification crucial, as misapplying a subterranean-focused solution will do nothing to stop drywood termites. Understanding how they live, reproduce, and damage structures helps homeowners appreciate why specialized strategies are necessary.

Independent Moisture Sources

Drywood termites derive the moisture they need from the wood they consume. This makes them uniquely adapted to dry climates like Southern California. They can infest roof timbers, attic beams, or furniture where no soil contact exists, making detection more difficult.

Direct Wood Infestation Patterns

Unlike subterranean termites, drywood termites do not build mud tubes. They enter directly into wood through small cracks or crevices, then create galleries inside. These internal colonies are hidden from view, which means infestations can persist for years without obvious signs.

Frass Production and Identification

A defining characteristic of drywood termite activity is the presence of frass, or termite droppings. These look like tiny, sand-like pellets that are often pushed out of small holes in the wood.

Swarming Behavior Differences

Drywood termite swarms usually occur in late summer or early fall. Swarms are smaller and less conspicuous than those of subterranean termites, which can make them harder to detect.

Structural Damage Patterns

Because drywood termites live and feed inside the wood, damage often remains hidden until the infestation is advanced.

Common Infestation Locations in Homes

Drywood termites are especially common in:

• Attics and roof framing

• Wooden siding and trim

• Window frames and doors

• Hardwood flooring and paneling

• Furniture, cabinets, and antiques
  

IV. Treatment Method Comparisons

The treatment approaches for subterranean termites and drywood termites differ significantly because their biology and habitats are so different. Subterranean colonies live in the soil, so treatments must target the ground and entry points into structures. Drywood colonies, however, live within the wood itself, so treatments must reach directly into infested areas or saturate entire structures. Using the wrong treatment wastes money and leaves infestations untouched.

For subterranean termites, treatments usually involve soil barriers, baiting systems, or targeted injections near active colonies. These approaches cut off access between the colony and the home while eliminating workers. For drywood termites, treatment often requires more invasive strategies, including whole-structure fumigation or direct heat applications. Foam injections can also be used for localized infestations. Each option comes with trade-offs regarding cost, disruption, and effectiveness, which is why professional evaluation is vital.

In Los Angeles, where both species are active, property owners need to understand that there is no universal solution. Choosing the wrong method can lead to repeated infestations and higher repair costs. Treatments must be species-specific and tailored to the conditions of each property. The comparison below highlights the most common approaches for each type of termite.

Subterranean Termite Treatments

Liquid Soil Barriers
Liquid termiticides are applied to the soil around a building’s foundation, creating a barrier that subterranean termites cannot cross.

Bait Station Systems
Bait stations are placed in the soil around the property. Termites feed on the bait and carry it back to the colony.

Spot Treatments
For smaller infestations, soil injections or targeted wood treatments can be used.

Drywood Termite Treatments

Whole-Structure Fumigation
The entire building is sealed, and gas is introduced to penetrate all wood surfaces.

Localized Heat Treatment
Heat treatment targets specific areas, such as attic beams or furniture.

Foam Injection Methods
Foam treatments are injected into drywood galleries, expanding to reach hidden areas. This is effective for smaller infestations. For a deeper look at foam vs soil treatments, review our foam and soil treatment comparison.

Cost and Effectiveness Analysis

• Subterranean termite treatments often involve higher upfront costs but provide long-term soil protection.

• Drywood treatments range from comprehensive fumigation to localized foam or heat, with costs varying by extent of infestation.
  

V. Prevention Strategies by Species

Prevention is always better than remediation when it comes to termite infestations. However, prevention strategies must be tailored to each species. Subterranean prevention revolves around controlling soil moisture, reducing wood-to-soil contact, and repairing leaks promptly. Drywood prevention, on the other hand, focuses on sealing wood, keeping attics ventilated, and avoiding the introduction of infested furniture.

Los Angeles homes are particularly vulnerable due to the region’s favorable climate for termites. Both species can remain active year-round, so annual inspections are essential. Simple environmental modifications also help reduce risks, such as improving airflow in crawl spaces, storing firewood away from the house, and maintaining landscaping to prevent excess moisture near foundations.

Prevention works best when it is based on accurate knowledge. Many homeowners rely on outdated beliefs about how termites spread or what keeps them away, which can lead to false confidence. Debunking termite myths provides clarity and helps ensure prevention strategies are effective.

Moisture Control for Subterranean Prevention

• Ensure gutters and downspouts direct water away from the foundation

• Repair plumbing leaks immediately

• Maintain proper soil grading to prevent pooling water

• Avoid wood-to-soil contact where possible
  

Wood Protection for Drywood Prevention

• Seal cracks and joints in wood with paint or varnish

• Store firewood away from the house

• Inspect furniture and wood before bringing them indoors

• Keep attics and crawl spaces well ventilated
  

Inspection Frequency Recommendations

Annual inspections are recommended for Los Angeles homes due to the presence of both species.

Environmental Modifications

Removing wood debris, reducing clutter, and ensuring proper airflow all help discourage infestations.

VI. Professional Assessment and Treatment Selection

The differences between subterranean termites and drywood termites highlight why professional identification is essential. Treatments must match the biology of the pest, and experts have the tools to detect colonies hidden deep within soil or wood. A professional inspection not only identifies the species but also determines the severity of infestation and the most effective course of action.

Attempting treatments without proper identification risks failure and recurring infestations. Professionals in Los Angeles use diagnostic processes to confirm which species is present, apply targeted treatments, and provide follow-up monitoring to ensure colonies are eliminated. Ongoing prevention and inspections further reduce risks, offering homeowners confidence that their property is protected.

Protect Your Home With Expert Care

Los Angeles homeowners dealing with termite infestations face unique challenges depending on whether subterranean termites or drywood termites are present. The differences in their biology, habits, and damage patterns make species identification crucial for effective termite control.

For expert diagnosis and safe, reliable solutions, contact Elite1 Termite Control, Inc..