Asian Lady Beetles and Boxelder Bugs: The Sun-Seekers on Your Siding

On a bright fall afternoon, step outside and look at the south or west side of your house. If you see dozens (or hundreds) of small bugs crawling on the siding, around window frames, or up near the eaves, you're probably looking at Asian lady beetles, boxelder bugs, or both.

These two are the sun-seekers of the fall pest world. Both gather on warm walls this time of year, and both are experts at finding the tiny gaps that lead inside. Here's how to tell them apart and what you can do about them.



Asian Lady Beetles: Not Your Garden Ladybug

Asian lady beetles were brought to the United States on purpose, to help farmers control aphids and other crop pests. Outdoors, they're helpful. Indoors, they're a headache.

How to identify them:

• About 1/4 inch long, round and dome-shaped
• Color ranges from pale tan or yellow to bright orange and red
• Can have many spots, a few, or none at all
• Look for a black "M" or "W" shaped mark on the white area just behind the head. That's the giveaway that it's an Asian lady beetle and not a native ladybug.

Why they're a problem:

• They come back every year. Lady beetles leave behind a scent that helps others find the same home. If you had them last fall, you'll likely see them again.
• They stain and smell. When threatened, they release a yellowish fluid from their legs. It smells bad and can stain walls, curtains, and furniture.
• They can bite. It's more of a pinch than a true bite, but it surprises a lot of people.
• Allergies. Large numbers of lady beetles indoors have been linked to allergy symptoms in some people.

Asian lady beetles are especially drawn to light-colored homes and buildings that stand out against their surroundings, like a house at the edge of a wooded lot. That's a lot of homes in the Chattanooga area and North Georgia.

Boxelder Bugs: The Red-and-Black Crowd

Boxelder bugs are easy to spot once you know what to look for.

How to identify them:

• About 1/2 inch long, flat and oval
• Black body with red or orange lines on the back and edges
• Young boxelder bugs (nymphs) are smaller and bright red

Why they're a problem:

• They gather in huge numbers. Boxelder bugs feed on the seeds of boxelder, maple, and ash trees. If you have those trees near your home, expect big crowds on sunny walls in the fall.
• They stain. Their droppings can leave reddish-orange spots on curtains, walls, and fabrics.
• They wake up on warm days. Boxelder bugs that slip into walls and attics often come out on warm winter days and early spring, confused and looking for a way back outside. That's why you might find them on windowsills in January.

The good news? Boxelder bugs don't bite people, damage your home, or eat your food.

Why Both Pests Love Your Sunny Walls

With our current mix of cool nights and warm afternoons, these insects are on the move. They warm up on walls that get the most afternoon sun, then crawl into any gap they can find: around window and door frames, under siding, through attic vents, and around pipes and wires.

Once they're inside your walls or attic, they settle in for the winter. When the house heats up, or on a warm winter day, some of them wander toward the light and end up in your living space.

Do's and Don'ts

Do:

• Vacuum up beetles and boxelder bugs indoors, then empty the bag or canister outside right away.
• Caulk cracks around windows, doors, trim, and siding.
• Replace worn weatherstripping and door sweeps.
• Make sure attic, soffit, and crawl space vents are screened and in good repair.
• Seal gaps where utility lines enter the home.

Don't:

• Crush lady beetles. It releases the smelly, staining fluid.
• Use bug bombs or foggers indoors. They don't reach insects hiding in walls and can create more mess than they solve.
• Wait until spring. By then, the bugs are already inside. Fall prevention is key.

Stop Them Before They Get In

The most effective way to deal with Asian lady beetles and boxelder bugs is to treat the outside of your home where they gather, before they find their way inside. GPM's Exterior Perimeter Control targets the areas these pests use to get in, and our monthly service keeps that protection going as the seasons change. You can learn more on our Lady Bugs and Beetles pages.

We're a family-owned, father-and-son team with over 40 years of hands-on experience, and we've been protecting homes across Chattanooga and North Georgia since 2006. If lady beetles or boxelder bugs are covering your house, give us a call at 423-517-7378 or get a quote online.