Pests in the High Country: What’s Creeping in as Temps Drop

Fall is Creeping In—So Are the Pests

The mornings are colder. The aspens are just starting to flash that unmistakable gold. Coffee tastes better in a hoodie on the deck. Fall is officially whispering its way into Summit County—and the pests? They’ve already started packing their bags for your house.

At Quality Pest Solutions, we know that as temperatures drop, pest activity actually heats up. Fall is one of the most important times of year to protect your home or business. It’s not just about comfort—it's about stopping the next infestation before it gets cozy in your crawl space.

Here’s what you need to know about mountain pest behavior in the fall, the biggest threats to homes in Summit County, and the steps you can take now to stay pest-free through winter.

Why Fall is Prime Pest Season at Altitude

In high-altitude climates like ours, seasonal transitions are extreme. Cold nights come faster, and animals—including insects, rodents, and ground-dwelling critters—start looking for survival solutions. And your warm, insulated home? That’s luxury real estate.

Here’s what drives pest pressure in the fall:

• Temperature drops: As nighttime temps dip into the 30s, pests instinctively seek warmth and shelter.

• Shrinking food sources: Outdoor vegetation dies back, pushing pests to hunt for alternative food indoors.

• Nesting instinct: Many species, especially rodents and spiders, start prepping for overwintering—building nests or egg sacs in undisturbed parts of your home.

This isn't just an inconvenience. Fall infestations can lead to full-blown winter problems if not handled early.

Top Fall Pests

Living in the Rockies comes with unique pest problems. Here’s who’s making moves right now—and why.

🐭 Mice & Voles

Once the first frosts hit, mice become extremely motivated. They can squeeze through holes as small as a dime, often entering through gaps in siding, door sweeps, garages, or crawlspace vents.

Voles, while less likely to enter structures, can wreak havoc on lawns and landscaping as they tunnel just beneath the surface. You might not see them—but you’ll see the damage come spring.

Signs to watch for:

• Droppings in drawers, pantries, or utility rooms

• Scratching sounds in walls or attic spaces

• Outdoor “runways” in your grass or mulch

🕷️ Spiders

Fall is spider mating season. That means they’re out and active—and likely to take shelter in basements, garages, and corners of rooms that don’t get much foot traffic.

Most species in Summit County aren’t dangerous, but their presence is still a sign of other insects (their food source). And nobody loves a surprise eight-legged roommate.

Pro tip: If you’re seeing more spiders, it usually means you’ve got other bugs inside, too.

🐜 Carpenter Ants

Unlike their lowland cousins, carpenter ants in high elevations stay active well into the fall—especially if they’ve already established a satellite colony in your walls or roofline.

These ants don’t eat wood, but they tunnel through it, which can weaken structural elements over time.

What to look for:

• Frass (sawdust-like debris) near baseboards or window sills

• Large black ants crawling inside, especially at night

• Rustling sounds in walls

🐝 Yellowjackets & Wasps

Fall is the end of the wasp lifecycle—but that doesn’t mean they’re done. In fact, this is when they’re at their most aggressive. Hungry, territorial, and less predictable, they often sneak into attics and siding gaps to hibernate.

Bonus hazard: Wasps love warm exhaust vents (like from your bathroom or dryer), and they’ll follow those warm air trails right inside.

🪰 Cluster Flies

If you’ve ever opened your window on a warm fall day and had a dozen sleepy flies buzz out, you’ve met the cluster fly. These guys don’t reproduce indoors, but they overwinter in attics, behind walls, and under siding—then reappear on sunny days.

They’re slow and harmless but incredibly annoying.

What You Can Do Right Now

Here’s the good news: with a little prevention and a solid plan, fall pest problems can be shut down before they start.

1. Seal the Gaps

Walk the perimeter of your home and look for:

• Cracks in foundation or siding

• Gaps around doors, windows, and utility penetrations

• Torn screens or unsealed attic vents

A little caulk or steel wool goes a long way. We also recommend upgrading door sweeps and installing weatherstripping if you haven’t in a few years.

2. Declutter Your Garage & Storage Areas

Pests love clutter—especially in places that don’t get much light or activity. Clear out cardboard, stored pet food, and forgotten corners of the garage or crawlspace. Use sealed plastic bins instead of open boxes.

If you’ve got firewood, store it at least 20 feet away from the house.

3. Check Attics, Crawlspaces, and Basements

These are the most common entry points for fall pests. Even if you’re not comfortable crawling around yourself, a visual check with a flashlight can help you spot:

• Spider webs

• Droppings

• Chewed insulation

• Entry holes or light coming in where it shouldn’t

  
  

4. Trim Back Vegetation

Shrubs, branches, and tall grasses that touch your home create natural pest highways. Trim anything that’s brushing up against siding or rooflines.

Bonus: This also reduces fire risk and improves your home’s curb appeal going into winter.

5. Schedule a Fall Inspection

We’re not just here for emergencies. A fall inspection from Quality Pest Solutions gives you peace of mind—and a game plan. We’ll walk your property, identify vulnerabilities, and treat proactively for the pests most likely to show up.

Why Early Fall Treatment Pays Off

We like to say pest control is like snow tires: better before the storm hits. Waiting until you see the problem often means it’s already bigger than you think.

Fall treatments can:

• Create a barrier before pests move in

• Knock down existing nests and colonies

• Prevent overwintering behavior that leads to spring infestations

And because many pests in our region hibernate or go dormant, treatments now mean fewer problems for months to come.

Your Local Pest Partner (Not a Franchise)

At Quality Pest Solutions, we’re proud to be Summit County’s family-run pest control team. We live here, we know these mountains, and we understand the unique challenges of high-altitude homes and businesses.

Our slogan—Mountain tested. Business and family approved.—isn’t just a tagline. It’s how we approach every job, from a one-time spider sweep to full-service commercial rodent control.

Don’t Wait for the First Snow

The cold is coming, and the pests already know it. If your home isn’t sealed and treated, you might be setting up a winter Airbnb for some very uninvited guests.

Let’s stop that before it starts.

📞 Call us today or book online for your fall pest checkup.

We’ll bring the backup. You enjoy the season.

Thank you for joining us on this informative journey through the world of Fall pest mitigation in Colorado's mountainous terrain. For more information or to schedule a pest treatment, contact Quality Pest Solutions at 970-485-4843 or visit our website

www.qualitypestsolutionsco.com/ Let us help keep your home and business pest-free, no matter the season.

Quality Pest Solutions - Your Trusted Partner in Pest Management in Mountainous Colorado.