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Subterranean Termite Control in Southern California
Subterranean termites are the most destructive termite species in the United States. Ultimate Termite provides Termidor liquid barrier and borate treatment across Orange County, LA County, the Inland Empire, and Riverside County.
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What Are Subterranean Termites?
Subterranean termites (Reticulitermes hesperus and related species) live in underground colonies that can number in the millions. They require moisture from soil contact and build mud tubes to travel above ground to reach wood in your home's structure.
They are the most destructive termite species in the US, responsible for the majority of termite damage. Unlike drywood termites, subterranean termites eat along the grain, leaving a honeycomb-like structure that can catastrophically weaken floor joists, support beams, and wall studs within 12–18 months of establishment.
Signs of Subterranean Termite Infestation
Mud Tubes on Foundation
Pencil-width tunnels of soil and debris running up foundation walls, pipes, or along the subarea. The clearest sign of subterranean activity.
Damaged Floor Joists
In the crawlspace or subarea, floor joists may show honeycomb-like damage along the grain. Wood may feel soft or crumble when probed.
Blistering Paint
Bubbling or blistering paint on interior walls can indicate subterranean termites tunneling close to the surface behind drywall.
Swarmers in Spring
Winged reproductive termites swarm in spring, often near soil-to-wood contact areas. They shed wings after mating — piles of wings indicate active swarming.
Important: Fumigation Does NOT Eliminate Subterranean Termites
Tent fumigation kills insects inside the structure but does not affect the underground colony. Subterranean termites live in the soil — fumigating the house leaves the colony intact. The correct treatment is a soil-applied liquid barrier such as Termidor (fipronil).
Treatment Options for Subterranean Termites
Termidor Liquid Barrier
The industry-standard treatment for subterranean termites. Fipronil is applied around the perimeter and under the slab. Termites spread it through the colony, eliminating the entire population within 90 days. 10+ year protection.
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Borate Treatment
BoraCare or Tim-bor borate is applied to wood surfaces in the subarea and framing. Effective as a preventive and for treating limited subterranean activity near wood-soil contact points.
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Frequently Asked Questions
What are mud tubes?
Mud tubes are pencil-width tunnels made of soil, wood, and debris that subterranean termites build to travel between the ground and above-ground wood. They protect the termites from predators and moisture loss.
Does fumigation work on subterranean termites?
No — fumigation kills insects inside the structure but does not affect the underground colony. Subterranean termites require a soil treatment such as Termidor liquid barrier.
What is Termidor treatment?
Termidor (fipronil) is a liquid barrier applied around the foundation. It is slow-acting so termites spread it through the colony via grooming and contact, eliminating the entire colony.
How long does Termidor last?
Termidor provides protection for 10+ years when properly applied. It binds to soil particles and remains effective even in rain.
Can I treat subterranean termites myself?
Not effectively — Termidor (fipronil) requires a licensed pest control operator and specialized equipment to apply correctly. DIY products are far less effective.
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