If you live in Metro Detroit, Ann Arbor, or anywhere in Southeast Michigan, you’ve probably seen them: clusters of black-and-red bugs lounging on your siding, windows, or porch this fall, congratulations—you’ve met the boxelder bug. These are boxelder bugs, and thanks to warmer-than-average fall weather, they’re still active in November 2025—and they’re looking for a cozy place to overwinter.
These almond-shaped insects, formally known as Boisea trivittata, are native to North America and especially fond of Southeast Michigan’s boxelder, maple, and ash trees. They’re about ½ inch long, black with red-orange markings, and they don’t bite, sting, or damage your home’s structure. But that doesn’t mean they’re welcome guests.
Boxelder bugs are sun-seekers. As temperatures drop, they gather on warm, sunny surfaces—especially the south and west sides of homes. From there, they slip through tiny cracks, vents, and gaps to overwinter in attics, basements, and wall voids. Once inside,they stick around until spring, occasionally popping out on warm winter days.
Nope! They don’t bite or sting. But they can be annoying. When crushed, they release a foul odor and leave behind reddish stains—especially on light-colored walls, curtains, and furniture.
Even though they’re not dangerous, boxelder bugs are a nuisance—and here’s why:
Boxelder bugs don’t come solo—they come in swarms. Homeowners across Southeast Michigan are seeing hundreds to thousands of these bugs clustering on sunny walls, windows, and siding (especially the south and west sides of homes). Once inside, they can hide in attics, wall voids, basements, and crawl spaces, making them hard to fully remove.
Boxelder bugs may not bite, but they definitely leave their mark—literally. When crushed or even disturbed, they release a rust-colored excrement that can stain just about anything it touches.
You might find these stubborn stains on:
These marks are especially noticeable on light-colored fabrics and surfaces, and they’re tough to clean.
As if the stains weren’t enough, boxelder bugs also come with a musty, foul odor. When squished, they release a scent similar to stink bugs. If you vacuum them without a sealed bag, that smell can linger in your vacuum and spread throughout your home.
So not only do they stain your stuff—they stink up your space. The best way to deal with them? Vacuum carefully, empty the contents outside, and clean your vacuum filter with warm, soapy water.
The entry points they use—the tiny cracks, gaps, and vents—can become open doors for other pests. Once these bugs find a way in, they unintentionally highlight weak spots in your home’s exterior. And guess what? Other pests are watching. These same entry points can attract:
In large numbers, their droppings and body parts can cause respiratory irritation or allergic reactions.
Even if you remove them, they come back year after year unless you take preventive action. They overwinter in homes and reappear on warm winter days, crawling out of vents, light fixtures, and window frames.
Here’s your fall checklist to stop these freeloaders from moving in:
Vacuum Them Up
Use a vacuum to remove bugs indoors—avoid squishing them to prevent stains and smells.
Empty vacuum outside immediately then Clean filters with warm, soapy water.
Keep It Clean
Wash exterior walls with soapy water to remove bug-attracting residue.
Seal Entry Points
Caulk cracks around your windows, doors, and siding.
Install weather stripping and door sweeps.
Repair screens on your doors and windows.
Screen off vents and utility openings.
DIY Bug Spray
Mix water with a few drops of dish soap in a spray bottle.
Spray directly on bugs outside—this dehydrates them safely.
If these little critters have already left their mark, don’t panic—here’s how to tackle stains on different surfaces:
Quick tip: Act fast! The sooner you treat the stain, the easier it is to remove.
If your home looks like a boxelder bug convention, it’s time to call in the pros. Safari Tree offers:
We service Southeast Michigan and can help you reclaim your home from these persistent pests.
Let’s kick those bugs to the curb. Call us or visit safaritree.com to schedule your fall pest control service.