- (301) 829-0060
- Mt. Airy, MD
- info@pestshieldinc.com
Pest Shield is a Mt. Airy-based pest management company serving Frederick homeowners since 2011 under Maryland Department of Agriculture license MDA #30263. Owner Troy Yowell holds Maryland certified applicator credential #19058 and brings roughly 35 years of pest management experience, including contract work protecting U.S. military bases overseas from disease-carrying insects. Entomologist Jeffrey Allwine on staff handles termite protection treatments and supports species-level identification when field findings need confirmation. Pest Shield holds a 5.0 rating across 338+ Google and HomeAdvisor reviews and was named Best of Frederick MD Pest Control in 2021.
How it works
Four steps. No surprises. Same answer whether it's your first call or your tenth.
You reach Troy or someone on his team directly. No call center, no dispatcher, no routing.
Same-day or next-day for most calls. Emergency stinging-insect situations and real-estate WDI deadlines get priority.
We identify the species, locate entry points, and find the source — not just the symptom.
Written recommendation, straightforward pricing, no obligation. If you don't need treatment, we'll tell you.
Most Frederick termite calls start with something a homeowner noticed — a small pile of wings on a windowsill, dirt-colored tubes running up a foundation wall, or wood that sounds hollow when tapped. The species responsible in this part of Maryland is the Eastern subterranean termite (Reticulitermes flavipes), which lives in the soil and travels into structures through hidden routes. By the time the signs are visible, a colony has typically been active for some time.
Frederick’s risk profile is higher than the regional average for a few reasons. The clay-heavy soils across Frederick County hold moisture against foundation walls, creating the sustained damp conditions subterranean termites need to survive. Older homes in Frederick’s historic core sit on stone, brick, or rubble-and-mortar foundations with more potential entry points than modern poured concrete. And wooded lots throughout the county put cellulose sources — stumps, root systems, mulch beds, firewood — close to structures, sustaining colonies that can then expand toward the house.
A single inspection visit can tell you whether what you’re seeing is active or old damage. That distinction matters: live infestations need treatment, while inactive galleries from a colony that’s already gone may not require any chemical application at all.
60+ years of combined experience. Tell us what you’re seeing — we’ll come look, no obligation.
Troy is a true professional. He accommodated my schedule by coming after hours to do an inspection. I had gotten a “free inspection” from another BIG, WELL-KNOWN company and they had me believing I had live termites. I was suspicious when they didn’t show up for the initial treatment, and more so when I got conflicting information from people at their company. Turns out I didn’t have termites, and Troy was straight up, didn’t try to rip me off with a service I didn’t need. He SAVED me $1400 and I will surely use him in the future if I ever have a pest problem of any kind! Go Pest Shield!
Marion Entwisle · June 2014 Read on HomeAdvisor →
Troy seems to genuinely like what he does and to educate his customers. He came to appointment ahead of time, explained things thoroughly, even taking me to crawl space under house to show where termites were entering house. Price was very competitive: price per linear foot was lower than other company and estimator from other company had included perimeter of a shed which, from my understanding, should not have been included because shed has no foundation, so not subject to invasion by termites. Work performed on time and as advertised. As indicated by others, a knowledgeable, competent and honest gentleman.
Otto Louis-Jacques · December 2015 Read on HomeAdvisor →
Troy was very friendly, knowledgeable, and professional. He was able to work with my historic home (with difficult access) and treat for my termite infestation. He was very reasonable with cost as compared to other quotes, especially the big pest companies (which I would not recommend). He was incredibly respectful of my newly planted grass and garden (as he had to maneuver his supplies through it to treat). He even helped to troubleshoot a leak in that part of the house. His communication was very clear and thorough as well. Initial inspection and treatment were prompt! Would definitely recommend.
Julia · May 2022 Read on Google →
General pest & rodent control
Every termite job at Pest Shield starts with a free inspection. Troy or Jeffrey Allwine walks the property — exterior foundation, crawl space if accessible, basement, and any reported problem areas — to confirm whether termite activity is present, identify the species, locate entry points, and assess the scope of the colony’s reach. Homeowners are walked through what’s been found, often shown the evidence directly, and given a straight answer on whether treatment is warranted. If it isn’t, Pest Shield says so. Troy is documented across the review record telling Frederick-area homeowners they don’t need treatment when the evidence doesn’t support it — in one well-known case, contradicting a “big, well-known company” that had convinced a customer she had live termites and saving her $1,400.
When treatment is warranted, Pest Shield delivers it under the Termite Warranty Plan, built around Termidor® HE:
| Element | Detail |
|---|---|
| Product | Termidor® HE — high-efficiency non-repellent termiticide |
| Application | One-time treatment around foundation perimeter, slabs, porches, and garage |
| Pricing | By linear foot of foundation perimeter |
| Colony eradication | Within 90 days of application |
| Residual effect | 15+ years in soil |
| Guarantee | 100% effective |
| Warranty | Lifetime renewable |
Termidor HE works through transfer. Termites can’t detect it, so they walk through treated soil, pick up the active ingredient on their bodies, carry it back to the colony, and pass it to nestmates through grooming and feeding. Within about 90 days the colony — including the queen — is eliminated, not just the workers visible at the structure. The treated soil zone remains a barrier for 15+ years, which is why a single application can carry a renewable warranty rather than a recurring contract.
After treatment, the property is documented in writing and the warranty paperwork explains exactly what’s covered going forward. Termidor HE is applied into the soil and slab penetrations around the foundation — not inside living areas — and is EPA-approved for use around occupied homes. The active ingredient binds to soil particles after application and does not move into the structure or into groundwater under normal conditions. For families with children and pets, this is one of the reasons it’s become the standard for residential subterranean termite treatment.
Owner
Founded Pest Shield in 2011 after years as a pest management contractor on U.S. military bases in Iraq and Afghanistan. Around 35 years in pest management. Personally handles or leads the majority of service calls.
Pest Management Specialist
Field technician handling residential and commercial service calls across Frederick, Carroll, and Montgomery counties.
Pest Management Specialist
Field technician handling residential and commercial service calls across the service area.
Our Entomologist
Consulting entomologist on species identification, conducive conditions, and treatment strategy for difficult cases.
Frederick sits at the eastern edge of the Catoctin Mountains where the Monocacy River cuts through clay-heavy Piedmont soil. The city’s historic district carries stone, brick, and mortar-and-rubble foundations dating to the 18th and 19th centuries, while surrounding county neighborhoods spread across wooded lots, former farmland, and creek valleys along Route 15, I-70, and I-270.
That mix matters for termites. Frederick County’s clay soils hold moisture against foundation walls year-round, creating the damp soil zone subterranean termites depend on. Older downtown foundations offer more cracks and mortar gaps than modern poured concrete, and wooded lots through Frederick and into Walkersville, Urbana, and Myersville keep cellulose — stumps, mulch, firewood — close to structures. For homeowners dealing with the full range of seasonal pest pressure in this area, pest control in Frederick covers the broader protection picture beyond termites alone.
Indoor swarmers almost always indicate an active termite colony in or under the structure. Subterranean termite swarmers emerge in Central Maryland from March through May, typically after a warm rain, and they look for light — which is why they show up at windows and door frames. Save a few in a sealed bag or jar if you can; species confirmation matters, and Jeffrey Allwine, Pest Shield’s on-staff entomologist, can verify whether what you’re seeing is a termite swarmer or a carpenter ant. Either way, a free inspection will give you a definitive answer before any treatment is recommended.
Termidor HE is a one-time liquid soil treatment applied around the foundation; bait stations are an ongoing monitoring system that requires regular inspection and replenishment. Termidor HE works because termites can’t detect it — they walk through treated soil, pick it up, carry it back to the colony, and transfer it to the queen and nestmates, eliminating the colony within about 90 days. The treatment remains effective in the soil for 15+ years, which is why Pest Shield’s Termite Warranty Plan covers it with a lifetime renewable warranty rather than a recurring contract.
The Termite Warranty Plan guarantees 100% effectiveness of the Termidor HE treatment and is renewable for the life of the home. If termite activity is found within the treated area during the warranty period, Pest Shield returns and addresses it at no additional charge for treatment. The warranty is renewed annually at a modest cost to keep coverage active. Specific terms, including any structural exclusions and renewal fees, are documented in writing at the time of treatment so you have a clear record of what’s covered.
Yes. Termidor HE is EPA-approved for residential use and is applied into the soil and slab penetrations around the foundation — not into living areas. The active ingredient binds tightly to soil particles after application and does not migrate into the structure or into groundwater under normal conditions. Once application is complete, families and pets can use the home and yard normally. Troy explains the application process and any short-term precautions during the inspection, before any treatment begins.
Yes, and that’s a common reason Frederick homeowners call. Second opinions are part of how Pest Shield operates — inspections are free, and Troy has a documented track record of telling homeowners they don’t have an active termite problem when the evidence doesn’t support one. In one well-known case, a “big, well-known company” had convinced a homeowner she had live termites; Troy’s inspection found none and saved her $1,400. If you’ve been quoted termite treatment and something feels off, call 301-829-0060 and we’ll come look before you commit.
