Last Updated: March 2026 | Audited by The PCC Research Team
If your inspector found brown mud tubes running up the side of your foundation, you have Subterranean Termites. Unlike Drywood termites, Subterranean termites live deep in the soil beneath your property and build massive super-colonies containing up to a million workers.
You cannot tent a house for Subterranean termites. Tenting gas only kills bugs above ground; it does not penetrate the dirt. To stop this species, you must attack them at the soil level using one of two professional methods: Liquid Trenching (Termidor) or In-Ground Bait Stations (Sentricon).
Method 1: Liquid Trenching (Termidor)
Liquid trenching is the gold standard for immediate subterranean termite eradication. The goal is to create a seamless, chemically treated barrier in the dirt completely surrounding your foundation.
How The “Transfer Effect” Works
Professionals use a non-repellent termiticide (like Termidor SC or Taurus SC). Because the termites cannot smell or detect the chemical, they walk right through the treated soil. The chemical binds to their bodies. When they return to the underground nest, they spread the poison to the rest of the colony through grooming and feeding (the “Transfer Effect”), effectively wiping out the Queen within 90 days.
The Intrusive Installation Process
Trenching is highly effective, but it is incredibly labor-intensive and invasive to your property. To establish the continuous barrier, the exterminator must:
- Digging: Dig a trench 6 inches deep and 6 inches wide in the dirt along the entire perimeter of your foundation.
- Rodding: Drive a long metal rod deep into the bottom of the trench every few inches to inject the liquid termiticide deep into the subterranean soil.
- Concrete Drilling: If you have a concrete patio, driveway, or garage slab touching your foundation, they cannot dig a trench. Instead, they must drill a 1/2-inch hole through your concrete every 12 inches, pump the chemical underneath the slab, and plug the holes with cement.
Method 2: Bait Stations (Sentricon)
If you do not want an exterminator drilling dozens of holes into your expensive stamped concrete patio or pumping hundreds of gallons of liquid chemicals into your soil, Termite Bait Stations are the modern alternative.
The most famous system is the Sentricon Colony Elimination System. Instead of creating a chemical barrier, this system uses the termite’s natural foraging behavior against them.
How Baiting Destroys the Colony
The technician places green plastic bait stations in the dirt around your home every 10 to 15 feet. Inside the stations is a cellulose bait matrix that termites actually prefer over the wood in your house. However, this bait is laced with a Chitin Synthesis Inhibitor (like Noviflumuron).
When the worker termites eat the bait, they don’t die immediately. They carry it back to the Queen and feed the colony. The chemical prevents the termites from molting (shedding their exoskeletons). Because they cannot molt, they die trapped inside their own skin, causing total colony collapse.
Termidor vs. Sentricon: Which is Better?
Both methods are scientifically proven to kill Subterranean termites, but they serve different homeowner needs.
| Feature | Liquid Trenching (Termidor) | Bait Stations (Sentricon) |
|---|---|---|
| Speed of Kill | Fast. Colony elimination usually begins within 30 to 90 days. | Slow. It can take 6 months to a year for the colony to find the stations and consume enough bait to collapse. |
| Intrusiveness | High. Requires digging up landscaping and drilling through concrete slabs. | Low. Stations are simply pushed into the soil. No drilling required. |
| Long-Term Cost | Paid upfront. The chemical barrier usually lasts 5 to 10 years before breaking down. | Requires an ongoing annual maintenance contract (usually $300/year) for the company to monitor and refill the stations. |
If you buy a house with Sentricon bait stations already installed in the yard, they belong to the pest control company, not you. If you cancel the annual monitoring contract, the company is legally allowed to come to your property, dig up the stations, and remove them. If you want permanent protection without a subscription fee, liquid trenching is the better investment.
Get a Subterranean Treatment Quote
Because trenching is priced by the linear foot, costs vary depending on the size and layout of your foundation. Contact a licensed California structural pest control operator to measure your property and compare Termidor vs. Sentricon pricing.
Call For Trenching Quotes: (866) 204-1751Frequently Asked Questions
Q: Can I buy Termidor and trench my own yard?
A: In California, the sale of Termidor SC (Fipronil) is heavily restricted to licensed professionals to prevent groundwater contamination. While you can find DIY termiticides online, properly trenching and drilling concrete requires commercial pumps and specialized rodding tools.
Q: Will the bait stations attract termites to my house?
A: No. Termite bait stations do not use chemical attractants or pheromones to “pull” termites from the neighborhood into your yard. Subterranean termites forage randomly. They simply intercept the termites that are already actively foraging near your foundation.
Q: Are termite bait stations safe for dogs?
A: Yes. The active ingredient (Noviflumuron) specifically targets the molting process of insects. Because dogs and humans do not have exoskeletons, the bait has virtually zero toxicity to mammals. Furthermore, the bait is locked inside a tamper-resistant plastic cylinder in the ground.