When you discover termites in or around your St. Louis home, the immediate question is: what’s the best way to get rid of them? For most homeowners, it comes down to two proven approaches — bait systems like Sentricon and liquid barrier treatments like Termidor. Both have been protecting homes for decades, and both work. But they work in fundamentally different ways, and the right choice depends on your specific situation, your property, and your long-term goals.

As a Certified Sentricon Specialist, Roberts Pest Control installs both Sentricon bait systems and liquid barrier treatments across the greater St. Louis metro. We are not here to sell you one over the other — we are here to give you an honest, side-by-side comparison so you can make the most informed decision for your home. If you already know you have termites, you can contact us directly for a free inspection. Otherwise, read on for a thorough breakdown of both options.

How Liquid Barrier Treatments Work

Liquid termite treatments — most commonly using Termidor (the brand name for the active ingredient fipronil) — work by creating a continuous chemical barrier in the soil around your home’s foundation. The process involves drilling small holes through concrete slabs, porches, and garage floors, then trenching along the exterior foundation walls. A professional-grade termiticide solution is injected into these channels, saturating the soil to form a treated zone that termites must pass through to reach your structure.

A typical liquid treatment for an average St. Louis home requires pumping 100 to 200+ gallons of chemical solution into the ground around the perimeter. When termites forage through this treated soil, they pick up the active ingredient and carry it back to nestmates through normal grooming and contact behavior. Fipronil is a “transfer effect” chemical, meaning it spreads through the colony — though it does not typically eliminate the entire colony the way a targeted bait system does.

Liquid treatments provide immediate protection. The moment the chemical is in place, any termite trying to access your home through that treated soil will be affected. The barrier typically remains effective for 5 to 10 years, depending on soil conditions, moisture levels, and the specific product used. However, the barrier can degrade over time — especially in Missouri’s clay-heavy soils, where freeze-thaw cycles and heavy rains can shift the soil and create gaps in coverage. When the barrier eventually breaks down, retreatment is necessary.

It is important to understand that a liquid treatment does not kill the colony itself. The colony continues to live and grow underground. You are blocking its access to your structure, but the termites are still there — foraging, expanding, and potentially finding untreated pathways to your home or neighboring properties.

How the Sentricon System Works

The Sentricon system takes a completely different approach. Instead of creating a chemical barrier in the soil, Sentricon uses a network of in-ground bait stations placed every 10 to 20 feet around your home’s perimeter. Each station contains a cellulose matrix laced with noviflumuron, an insect growth regulator that disrupts molting — a biological process termites cannot survive without.

Here is why this matters: termites are constantly foraging. Subterranean termites can maintain foraging tunnels spanning the length of a football field. When foraging workers encounter a Sentricon station, they feed on the bait and recruit other colony members to the food source — standard termite behavior. As noviflumuron spreads through the colony via feeding and grooming, workers begin to die during their next molt cycle. Because the queen depends on workers to feed and care for her, the colony structure collapses. This is what Corteva Agriscience (the manufacturer) calls Colony Elimination Technology — it does not just block termites, it kills the entire colony, including the queen.

Modern Sentricon stations use Always Active technology, meaning the bait is present from day one. There is no outdated “monitoring only” phase where stations sit empty waiting for termites to arrive. Your protection starts the moment the stations are installed. The bait matrix is also designed to be more attractive to termites than wood, based on extensive university research.

Sentricon has earned the EPA’s Presidential Green Chemistry Challenge Award — the only termite control product to receive this recognition. It protects landmarks including the White House, the Statue of Liberty, and Independence Hall. Across 70+ peer-reviewed studies, Sentricon has demonstrated consistent colony elimination in every climate and soil type tested.

Side-by-Side Comparison

When Liquid Treatment Makes Sense

Liquid barrier treatments are not obsolete — there are situations where they are the better tactical choice. If you are dealing with an active infestation and need immediate knockdown, a liquid treatment can stop termites from entering your home within hours of application. The transfer effect of modern termiticides like Termidor means affected termites will spread the chemical to nestmates, providing meaningful colony suppression even if full elimination is not guaranteed.

Liquid treatments also tend to carry a lower upfront cost compared to Sentricon installation plus annual monitoring. For homeowners working within a tight budget, or for properties where a bait system is not the best structural fit — such as homes with extensive hardscaping, very narrow perimeters, or unusual construction — a liquid barrier may be more practical.

In some cases, the smartest approach is a combination treatment: liquid termiticide applied to active infestation areas for immediate protection, with Sentricon stations installed for ongoing colony elimination and long-term monitoring. We recommend this dual approach for severe infestations or high-risk properties. Learn more about our termite treatment options.

When Sentricon Is the Better Choice

For the majority of St. Louis homeowners, Sentricon offers advantages that liquid treatments simply cannot match. If you plan to stay in your home long-term, Sentricon’s ongoing monitoring and colony elimination provides continuous protection that does not degrade over time the way a liquid barrier does. Every year your stations are serviced, every year you are protected.

If you have environmental concerns, Sentricon is the clear winner. There are zero chemicals pumped into your soil — the active ingredient is contained entirely within locked, tamper-resistant stations. This is especially important for properties with wells, gardens, koi ponds, or water features nearby, where soil saturation with termiticide raises legitimate groundwater concerns.

Sentricon is also ideal for new construction — pre-construction Sentricon systems can be installed before the foundation is poured, providing protection from day one without the need for drilling or trenching. And because Sentricon comes with a warranty-backed monitoring program, you get professional inspections and station maintenance as part of the package. If a new colony moves into range, your stations are already there to intercept it. Check our pest control cost guide for detailed pricing information.

What Roberts Pest Control Recommends

After years of installing both systems across the St. Louis metro area, our honest recommendation is this: for most homes, Sentricon is the better long-term investment. The reason is straightforward — colony elimination means you are solving the termite problem, not just managing it. A liquid barrier keeps termites out of your house, but the colony is still thriving underground. With Sentricon, the colony dies.

The Always Active technology means there are no gaps in your protection. From the moment stations go in the ground, bait is present and available. There is no waiting period, no empty monitoring stations, no hoping termites find the right spot. And with annual monitoring, our technicians physically inspect every station, replace bait as needed, and check for new termite activity — catching problems before damage starts.

Roberts Pest Control is a Certified Sentricon Specialist. That means we are trained, authorized, and held to the manufacturer’s standards for installation and monitoring. Not every pest control company in St. Louis carries this certification. That said, we also install liquid treatments when the situation calls for it — active infestations that need immediate intervention, budget-sensitive situations, or combination treatments for maximum protection. We will give you an honest recommendation based on your property, your risk factors, and your goals — not a one-size-fits-all sales pitch.

Frequently Asked Questions