- (301) 829-0060
- Mt. Airy, MD
- info@pestshieldinc.com
Pest Shield has been treating wood-destroying insects across Frederick County since 2011, operating under Maryland Department of Agriculture license #30263. Owner Troy Yowell holds Maryland certified applicator credential #19058 and brings roughly 35 years of pest management experience, including years protecting U.S. military bases overseas from disease-carrying insects. On-staff entomologist Jeffrey Allwine handles species-level identification for wood-destroying insect cases when field ID isn’t conclusive. The company has earned 338+ five-star reviews and was named Best of Frederick 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.
If you’re seeing large black or red-black ants inside your Frederick home — especially in kitchens, around window frames, or emerging from baseboards — you’re likely dealing with carpenter ants, not a nuisance ant species. Carpenter ants (*Camponotus pennsylvanicus*) are classified as wood-destroying insects in Maryland because they excavate galleries inside structural wood. By the time workers appear indoors, the colony is often already established somewhere you can’t see.
Here’s what to look for:
The confusion most homeowners run into is telling carpenter ants apart from termites. Carpenter ants have pinched waists, bent antennae, and forewings noticeably longer than their hindwings. Termites have straight-sided bodies, straight antennae, and four wings of equal length. Both produce winged swarmers in spring, and both indicate structural concern — but treatment and biology differ, and getting the ID right matters.
The structural risk is real. Carpenter ants prefer moisture-softened or previously damaged wood, which is exactly what’s available in older Frederick homes — sill plates above damp crawl spaces, fascia behind clogged gutters, framing near a slow plumbing leak, deck posts in soil contact. A satellite colony in a wall void can expand for years before any visible sign reaches the interior. One-time treatments that target visible workers without addressing the colony location and conducive conditions tend to suppress activity briefly and let it return.
60+ years of combined experience. Tell us what you’re seeing — we’ll come look, no obligation.
The technician was thorough and reassuring, as well as answering my questions with his in-depth knowledge of termites and carpenter ants. I would recommend Pest Shield to my neighbors and friends.
Sherry Nicholson · August 2014 Read on HomeAdvisor →
Pest Shield, Inc. We had a mice problem and they eradicated the situation. They were thorough and professional and super friendly. I will definitely be hiring them again if needed and would recommend them to anyone who needs pest control.
Kim Mercer · March 2020 Read on HomeAdvisor →
Troy from Pest Shield, inc. called immediately and did a home inspection, but felt that there was no significant problem at the time…some wet wood (a column) that needs to be addressed first, then see if there is truly an issue with carpenter ants. I appreciate his honesty in not pushing pesticide treatments before pursuing other solutions first….no cost for inspection…
Ruth Carson · July 2013 Read on HomeAdvisor →
General pest & rodent control
Because carpenter ants are wood-destroying insects, Pest Shield treats them under the same framework used for subterranean termites — the Termite Warranty Plan, built around a one-time Termidor® HE application. Troy or Jeffrey Allwine begins with a free inspection: a walk of the exterior perimeter, foundation, porch and deck attachments, crawl space access where present, and any interior areas where activity has been reported. The goal is to confirm species, locate the parent and satellite colonies, identify the moisture conditions feeding them, and map the entry pathways into the structure.
Treatment is a single perimeter application of Termidor® HE, the same EPA-registered termiticide Pest Shield uses for subterranean termite work. Termidor is non-repellent — carpenter ants can’t detect it, so they walk through the treated zone, carry the active ingredient back into the colony on their bodies, and transfer it through normal grooming and feeding contact. This is why a one-time treatment reaches the queen and the satellite colonies rather than just killing the workers you happen to see.
Operational details for the Termite Warranty Plan:
After treatment, Troy walks you through what to expect: typically a brief uptick in visible ant activity over the first two to three weeks as the active ingredient moves through the colony, followed by a sharp decline and full silence by the 90-day mark. You’ll also get specific recommendations for the conducive conditions feeding the problem — wood mulch pulled back from the foundation, gutter and downspout corrections, addressing wood-to-soil contact at deck posts, fixing the moisture source behind a stained ceiling. Termidor® HE is EPA-approved and applied to exterior soil and structural perimeters, not living spaces. There is no need to leave the home during treatment, and the application is safe for families with children, pets, and pollinator-friendly plantings once it dries into the soil.
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 where the Monocacy River cuts through the Catoctin foothills, and the housing stock reflects more than two centuries of building — pre-1900 brick rowhomes downtown, mid-century wood-frame neighborhoods along Route 15 and the Route 40 corridor, and newer construction pushing toward Urbana, Walkersville, and Ballenger Creek along wooded edges.
That mix matters for carpenter ants. Older Frederick homes carry the moisture-prone framing, crawl spaces, and wood sill plates these colonies prefer. Mature tree canopy, wood mulch beds, and proximity to the Monocacy watershed keep humidity high through Frederick’s long humid summers — the exact conditions that soften structural wood and turn a wooded backyard into a launching point for satellite colonies. Homeowners dealing with these pressures often benefit from comprehensive pest management in Frederick that addresses the full range of insects these conditions attract.
Look at the body, antennae, and wings. Carpenter ants have a pinched, narrow waist, bent (elbowed) antennae, and forewings clearly longer than their hindwings. Termites have a straight-sided body with no visible waist, straight antennae, and four wings of equal length. Damage also differs — carpenter ant galleries are smooth and sandpapered clean, while termite damage is packed with mud and soil. If you’re unsure, Pest Shield’s free inspection includes species confirmation, and Jeffrey Allwine handles laboratory ID for samples when field identification isn’t conclusive.
It’s a one-time treatment. Because carpenter ants are classified as wood-destroying insects, Pest Shield treats them under the Termite Warranty Plan with a single application of Termidor® HE rather than the recurring 60-day Standard Care Plan used for general ant control in Frederick. One perimeter application reaches the colony through transfer between workers, and the product’s 15+ year residual means you’re not paying for repeat sprays. The lifetime renewable warranty covers re-treatment if activity returns.
Termidor® HE is a non-repellent termiticide, which means carpenter ants can’t detect it and walk through the treated zone normally. They carry the active ingredient back to the colony on their bodies and transfer it through grooming and feeding contact, which reaches the queen and satellite colonies a contact spray would miss. You’ll typically see a brief uptick in visible activity over the first two to three weeks as the product moves through the colony, then a sharp decline. Full colony eradication occurs within 90 days.
If carpenter ant activity returns within the warranty period, Pest Shield returns and re-treats at no additional charge — that’s the 100% effective guarantee. The warranty renews annually for the life of the home under your ownership, which is why it’s called lifetime renewable. Termidor® HE itself remains active in the soil for 15+ years, so renewals are about maintaining the warranty coverage, not redoing the treatment. Troy explains the renewal terms in plain language at the time of service.
Yes. Termidor® HE is an EPA-approved termiticide applied to exterior soil along the foundation perimeter and to structural elements like porch slabs and garage edges — not to living spaces or food prep areas. Once the application dries into the soil, the treated zone is safe for children, pets, gardens, and pollinator plantings. You don’t need to leave the house during treatment, and there’s no need to remove pet bowls or cover play areas inside. If you have specific concerns about a sensitive area on your property, Troy will walk it with you during the inspection.
