Pests that Invade Your Home in Fall

Learn about some of the pests that try to invade your home when the weather starts to turn cold in fall.

As it starts to become chilly in the fall, insects like stink bugs and Asian lady beetles begin to seek out warmth. With its shelter from cold winds and rain and furnace-fed warmth, your home is just the place these pests have in mind. In order to stop them from entering your living space, it's important to take steps to pest-proof all of the places they could get in.

The Top Home Invaders

Here are some of the pests that look to move inside when outdoor temperatures start to drop.

Asian Lady Beetle

When they’re outdoors, Asian lady beetles are an important predator of the aphids and scale insects that can plague your landscape. But when they come indoors, they’re a nuisance. Asian lady beetles range in color from pale tan to reddish orange and can have lots of spots or no spots at all.

While other lady beetles (a.k.a. “Ladybugs”) are round, this type is oval. When disturbed, Asian lady beetles can produce a foul-smelling, yellowish liquid that can stain surfaces. In the fall, they enter your home to hibernate through the winter and then become active again in spring, which is when you’ll find them crawling around your windows and walls.

Boxelder Bug

Boxelder bugs appear most often in areas that have boxelder trees. Their bodies are about a half-inch long and are black with red or orange markings. On warm, sunny days in early fall you can find boxelder bugs congregating on the south-and west-facing sides of buildings.

When looking for a suitable place to overwinter, these pests will typically fly just a few blocks, but they have also been known to occasionally travel as far as several miles. During the winter, boxelder bugs are generally inactive, but on those occasional mild, sunny days, you may find them moving around near windows and other sunny areas. Try not to crush them, as they make an awful smell—and may bite.

Learn more about boxelder bugs

Stink Bugs

While stink bugs don’t bite and aren’t interested in your food, these shield-shaped insects produce a distinctive smell (some compare it to rotting fruit) that can linger in a room. They range in color from green to brown and are about the size of a dime. Like the boxelder bug, they may become active on mild, sunny days in the winter, and you’ll discover them climbing walls and along counters.

Learn more about stink bugs

Scorpions

If you live in the southern U.S., you may find scorpions seeking shelter in your home (especially in basements or cellars) as the night temperatures begin to dip below 75 degrees F. Part of the arachnid family, scorpions have long, slender bodies and 5-segmented tails tipped with a stinger. Their size depends on which species they belong to. Scorpions hunt for food (insects, spiders, centipedes, and even other scorpions) during the evening hours and hide during the day.

Learn more about scorpions

How to Kill & Prevent Fall Invading Pests

The best way to combat these pests in your home is to stop them from coming inside in the first place. In late summer, repair or replace worn-out weather-stripping around doors, mend holes in window and door screens, and seal other cracks and crevices around your home’s foundation. Create a bug-barrier by applying Ortho® Home Defense® Insect Killer for Indoor & Perimeter2 around doors, windows, other entry points, and around the perimeter of your home. Before bringing any plants indoors for the winter, carefully inspect them for hitchhikers.