- (301) 829-0060
- Mt. Airy, MD
- info@pestshieldinc.com
Pest Shield has been treating spider activity in Frederick County homes since 2011, operating under Maryland Department of Agriculture license #30263 with a team carrying over 75 years of combined pest management experience. Owner Troy Yowell brings roughly 35 years in the industry, and on-staff entomologist Jeffrey Allwine handles species-level identification when field ID isn’t conclusive. The company was voted Best of Frederick, MD Pest Control in 2021 and Best of Nextdoor four years running from 2021 through 2024. Every new client relationship starts with a free inspection — no pressure, no upsell.
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.
Spiders show up indoors because they’re following food. If you’re finding webs in basement corners, spiders in window frames, or one scurrying across the garage floor, the underlying issue is rarely the spiders themselves — it’s the insects already in your home that are drawing them in. Treating only what you can see usually means the problem returns within weeks.
The most common signs Frederick homeowners notice:
The species most often encountered in Central Maryland homes include the common house spider (Parasteatoda tepidariorum), the cellar spider (Pholcus phalangioides, often called “daddy long-legs”), and wolf spiders (Hogna and other Lycosidae species). None of these are medically significant. Black widows (Latrodectus mactans) are present in Maryland but typically stay in undisturbed outdoor locations like wood piles and sheds. Brown recluse spiders (Loxosceles reclusa) are uncommon here, though they’re occasionally encountered and warrant professional identification rather than guesswork.
A one-time interior spray will knock down what’s visible today, but spiders reinfest from outside within weeks because the conditions that attracted them — entry points, harborage, and prey insects around the foundation — haven’t changed. That’s the gap ongoing exterior treatment is built to close.
60+ years of combined experience. Tell us what you’re seeing — we’ll come look, no obligation.
We chose Pest Shield after contacting a few different pest control companies because we liked how Troy took his time to explain his experience and the science behind the products he uses. Troy has been working with us to manage two separate infestations and he has been incredibly generous with his time, energy and expertise. After speaking with my husband, he offered to come out the same day and as he inspected the house, he offered useful suggestions for ways to manage other things like spiders in the windows. We have a young son who is immunocompromised and Troy was very respectful of the safety precautions that we are currently taking. We are so grateful for his knowledge, promptness and kindness.
Erin Swen · December 2021 Read on Google →
Troy was excellent. He came on time and was very friendly and professional. He explained everything in great detail and did the inspection and treatment same day. The inspection was very thorough. Price was reasonable compared to other pest companies. I highly recommend Pest Shield.
Gosia Riebman · July 2022 Read on HomeAdvisor →
Troy was a pleasure to work with. Fingers crossed that the ants don’t come back. Got the yearly protection plan.
John Dickerson · August 2016 Read on HomeAdvisor →
General pest & rodent control
Pest Shield‘s spider control approach starts from the outside. As Troy puts it — and as customers have repeated in reviews — “Pest Shield treats your house primarily from the outside to prevent pests from ever getting into your house and keeps the chemicals out of your home.” For spiders specifically, that exterior-first method matters: spiders reinfest from outside, and the prey insects feeding them are concentrated around the foundation, soffits, window frames, and entry points. Treat the perimeter, and you interrupt both populations at once.
Every new client relationship begins with a free inspection. Troy or one of the technicians walks the property to identify spider activity, locate harborage areas (cracks, soffits, foundation gaps, basement window wells), and assess the broader pest pressure that’s sustaining the population. If a sample needs species-level confirmation — particularly if there’s any concern about a venomous species — Jeffrey Allwine handles laboratory identification.
For ongoing protection, Pest Shield’s Standard Care Plan is the service that holds results:
When the initial inspection turns up a heavy interior population, the first visit includes targeted indoor treatment in addition to the exterior perimeter — egg sacs removed where accessible, web sites treated, and harborage points addressed. From there, the recurring 60-day cycle maintains the result.
Products are EPA-approved, and nontoxic bio-pesticide options are available for households with children, pets, or family members with sensitivities. Troy has been documented proactively cautioning customers about treatment around young children and adjusting the approach accordingly. The exterior-first method itself is part of the safety profile — chemicals stay outside the living space whenever possible.
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 Catoctin Mountain foothills meet the agricultural valley along the Monocacy River, with US-15 and I-70 cutting through neighborhoods that range from historic downtown rowhomes to wooded suburban lots on the city’s edges. The mix of older housing stock, mature tree cover, and surrounding farmland creates year-round pest pressure that supports both spider populations and the insects they hunt.
Frederick’s older homes — particularly those with unfinished basements, stone foundations, and crawl spaces — provide ideal spider harborage, and the city’s humid summers sustain the prey insects drawing spiders indoors. Late August through October brings peak indoor sightings as spiders mature and shift toward warmer shelter, which is when most pest control in Frederick service calls come in.
Because spiders reinfest from outside, and the insects they feed on are still around your foundation. A one-time interior spray kills what’s visible but doesn’t change the conditions drawing spiders in — entry points, harborage near the foundation, and prey insects in your yard and along the perimeter. Pest Shield’s Standard Care Plan addresses this with exterior treatment every 60 days, which interrupts both the spiders and the prey population. If activity reappears between scheduled visits, retreatment is included at no charge.
Almost certainly not. The common house spider, cellar spider, and wolf spider — the three you’re most likely encountering in Frederick homes — are not medically significant. Black widows are present in Maryland but typically stay in undisturbed outdoor spots like wood piles and sheds. Brown recluse spiders are uncommon in this region but occasionally turn up; if you find a spider that concerns you, save it in a sealed container and we can have our on-staff entomologist confirm the species before recommending anything.
Most Frederick service calls are scheduled same-day or next-day. Call (301) 829-0060 and you’ll speak directly with Troy, an office staff member, or a technician — no call center, no dispatcher. Troy assesses the situation on the phone and schedules accordingly. The first visit is a free inspection, with no obligation to enroll in a service plan.
Yes. Pest Shield uses EPA-approved products and offers nontoxic bio-pesticide options for households with children, pets, or family members with sensitivities. The exterior-first treatment approach is itself part of the safety profile — most of the work happens outside the living space, which is why customers with crawling babies, dogs, and immunocompromised family members have specifically chosen Pest Shield in their reviews. Troy will discuss the specific products and any precautions during the inspection.
The Standard Care Plan covers general pest pressure — ants, crickets, silverfish, stink bugs, centipedes, water bugs, rodents, and the other insects that often drive spider activity in the first place. That’s part of why the plan works for spider control specifically: addressing the prey insects around your foundation reduces what’s drawing spiders in. The bi-monthly 60-day cadence is more frequent than the standard quarterly schedule most companies offer, and the 100% effective guarantee means free retreatment between scheduled visits if anything covered reappears.
