As temperatures drop and leaves begin to fall, you may notice a sudden swarm of odd-looking black and red bugs gathering around your windows, siding, and doors. These are boxelder bugs, and while they aren’t considered a common indoor pest, a boxelder bug infestation can still be frustrating, unsightly, and difficult to manage without the right approach.
Read on to know more about what boxelder bugs are, their life cycle, what attracts them, the common signs of a boxelder bug infestation, and exactly how to get rid of boxelder bugs for good.
What Are Boxelder Bugs?
Boxelder bugs (Boisea trivittata) are native to North America and are classified as true bugs, related to stink bugs and cicadas. They are named after the boxelder tree, which is a fast-growing type of maple native to North America. These trees commonly grow near rivers, in yards, and throughout urban landscapes.
Boxelder trees are dioecious, meaning they have separate male and female trees. Female boxelder trees produce clusters of small, greenish-yellow flowers in the spring. As the season progresses, these flowers develop into distinctive seeds called ‘samaras,’ which are flat, winged seeds that spin like helicopters when they fall to the ground.
These seeds hang in long, drooping clusters and turn from green to light brown as they mature. The combination of abundant seeds, accessible bark, and ample leaf cover makes female boxelder trees an ideal habitat for feeding, mating, and egg-laying. In contrast, male boxelder trees produce pollen-bearing flowers but do not develop seeds, making them less attractive to boxelder bugs overall.
What Do Boxelder Bugs Look Like?
Adult boxelder bugs are about ½ inch long with a flattened, oval-shaped body. They’re mostly black with vivid red or orange markings along the thorax and wings. When at rest, their wings lie flat over the back and form a distinctive ‘X’ pattern.
They also have six legs and long, straight antennae, giving them a sleek, recognizable silhouette. Meanwhile, their nymphs (young boxelder bugs) are smaller, bright red, and wingless. As they mature, they gradually develop darker bodies and wings.
Boxelder bugs are also often mistaken for other pests, particularly stink bugs and milkweed bugs. However, there are clear differences. Stink bugs have a broader, shield-like shape and come in duller colors, such as brown or green, lacking the bright red accents of boxelder bugs. Milkweed bugs, on the other hand, share similar red and black coloring but have a more robust body and a different wing pattern, with orange-red bands crossing the back rather than outlining the wings.
The Boxelder Bug Life Cycle
The boxelder bug life cycle helps explain their seasonal behavior and provides insight into the best times to take action. They follow a seasonal pattern:
- Spring (emergence and mating): After overwintering in wall voids, attics, or outdoor crevices, adult boxelder bugs emerge in early spring. They seek out host trees, mostly female boxelder, ash, and maple trees, to feed on new plant growth and to mate.
- Late spring to early summer (egg-laying): Females lay clusters of tiny, rust-colored eggs in tree bark cracks, leaves, or even on siding. Eggs hatch within 10 to 14 days. These bugs typically produce 2 generations per year, especially in warmer climates.
- Summer (nymph development): Nymphs go through several molts over the summer months, feeding on leaves, flowers, and developing seeds of host trees. By late summer, nymphs mature into adults.
- Fall (migration): As days shorten and temperatures drop, adult boxelder bugs begin to migrate toward warmth. That’s when they show up en masse on the sunny sides of buildings, often your home.
- Winter (dormancy): Boxelder bugs become inactive during winter, often inside walls, attics, or behind siding. They may reappear indoors during warmer days, giving the impression of a new boxelder infestation even in the cold months.
What Attracts Boxelder Bugs to Your Home
If you’re wondering why your house seems to be the chosen destination for these bugs, there are several reasons why they might be migrating to your living room:
- Boxelder and maple trees: The primary food source for boxelder bugs is the seed pods, flowers, and leaves of boxelder and maple trees. If your property has female boxelder trees or other seed-bearing maples near your home, you’re at higher risk of a boxelder bug infestation.
- Warmth, sunlit surfaces: They especially like to gather on south- and west-facing walls because these get the most sunlight, and they’re even more attracted to light-colored walls that hold heat longer.
- Entry points: As temperatures drop, boxelder bugs seek ways to enter homes through vents, siding gaps, window frames, doorways, and rooflines to find a warm place to overwinter.
- Overwintering shelter: Boxelder bugs don’t tolerate cold well, so they seek out warm structures to hibernate in through the winter. They don’t reproduce indoors but can become active on warm winter days and accidentally enter your living space.
Are Boxelder Bugs Dangerous?
No, boxelder bugs are not considered dangerous to humans or pets. They do not sting or transmit disease and are generally not known to bite, though there are rare reports of defensive biting. They do pose several inconveniences.
For instance, their excrement leaves rusty-orange marks that can stain surfaces, especially light-colored curtains, furniture, and walls. If crushed, they release a foul odor similar to that of stink bugs, which can linger and add to the unpleasantness.
In rare cases, handling them may cause mild skin irritation due to the compounds they secrete. While they’re not physically harmful, the presence of a boxelder bug infestation can significantly impact your comfort and the cleanliness of your living space.
5 Signs of a Boxelder Bug Infestation
Unlike termites or bed bugs that stay hidden, boxelder bugs are quite visible. Look for the following signs to confirm a boxelder bug infestation:
- Large numbers on exterior walls: In fall, you may see hundreds of boxelder bugs sunning themselves on the southern or western walls of your home.
- Presence indoors: If you see boxelder bugs inside your home, particularly in window sills, ceiling light fixtures, or even slowly crawling across the floor, it likely means they’ve found a way in through cracks or gaps. They often remain hidden in wall voids or attics during winter, only emerging on warm days.
- Clusters around entry points: Groups of boxelder bugs near baseboards, door frames, attic vents, or gaps around window screens suggest they’re actively trying to enter or have succeeded in getting into your home.
- Red or rust-colored stains: Small, reddish stains on light-colored curtains, painted walls, or upholstered furniture are often left behind by the excrement of boxelder bugs. These marks can also appear if the bugs are accidentally crushed.
- Foul odors: A musty smell may develop if a large number of boxelder bugs have died in wall voids or attics.
How to Get Rid of Boxelder Bugs + Prevention Tips
Dealing with boxelder bugs requires a two-pronged approach: eliminating those that are already inside and preventing new ones from entering. Below are ways on how to get rid of boxelder bugs and some prevention tips to keep them from coming back for good:
Spray with Soapy Water or Bleach Solution
A simple way to kill boxelder bugs on contact is by using a homemade soapy water solution. Mix several tablespoons of dish soap with water in a spray bottle and spray it directly onto the bugs. The soap breaks down their waxy outer coating, causing them to dehydrate and die. This is especially useful for treating clusters on the outside of your home, particularly on sunny walls.
Alternatively, a diluted bleach and water spray can also eliminate these pests when applied directly. However, take care when using bleach: avoid spraying it on plants or any surfaces that could be damaged, and ensure good ventilation if you apply it indoors.
Always spray directly on the bugs for best results, and be prepared to reapply if the bugs return. For less harsh options, you can also knock them into a bucket of soapy water to drown them or use a strong spray from a garden hose to wash them off exterior walls and trees.
Vacuum Visible Bugs
If boxelder bugs make their way indoors, resist the urge to squash them. Instead, use a vacuum with a high-efficiency particulate air (HEPA) filter to remove them cleanly and efficiently. Immediately empty the vacuum contents into a sealed bag and dispose of it outside to prevent the bugs from crawling back out.
After vacuuming boxelder bugs, be sure to promptly clean the areas where they were removed using soapy water to eliminate any lingering residue or odors.
Seal Up Entry Points
Inspect your home’s exterior for cracks and openings, and seal them with caulk or weatherstripping. Repair torn window screens, add door sweeps, and use fine mesh to cover attic or soffit vents to block common access points.
Trim or Remove Female Boxelder Trees
Removing female boxelder trees or replacing them with male varieties can significantly reduce the local bug population. However, this won’t eliminate all of them, and it’s not a permanent fix, as the bugs can still fly in from neighboring trees.
If tree removal isn’t possible, regularly clean up fallen seeds and leaves beneath and around them. Boxelder bugs also shelter in piles of leaves, rocks, boards, overgrown shrubs, and dense plants, so clearing these areas helps limit their habitat. For added defense, maintain a 6-to 10-foot-wide cleared zone around your home by mowing weeds, trimming grass, and raking away debris.
Use Natural Deterrents
Diatomaceous earth is a natural option that kills bugs by dehydrating them. Sprinkle it along foundation lines, entryways, and window sills where bugs are likely to crawl. Be sure to apply this powder carefully, avoiding direct contact with the skin and inhalation. You may also use sprays made from neem oil or essential oils, such as peppermint, citrus, clove, or lavender, around doors and windows to repel them.
Use Insecticides Sparingly and Carefully
Insecticide sprays are generally not the best solution for boxelder bug control, as they often work no better than vacuuming or hosing and may require repeated applications. For outdoor control, insecticidal soaps can reduce nymph populations on tree trunks. At the same time, pyrethroid insecticides, such as cyfluthrin or deltamethrin, may be used to spot-treat clusters on walls or foundations.
Larger infestations on trees might require treatments with chemicals such as malathion or carbaryl. These should only be applied by certified pesticide professionals to avoid harmful runoff into nearby water sources.
Also, indoor insecticide sprays or foggers for boxelder bugs are usually not recommended because they must be sprayed directly or crawl over treated surfaces for the insecticide to be effective. Such treatments can also leave pesticide residues on household surfaces.
Overall, insecticides should be considered a last resort. It should be used carefully and sparingly in combination with physical removal and preventive measures.
Call a Professional
If you’re struggling to control a persistent boxelder bug infestation despite trying various DIY methods, it may be time to seek professional help. Pest control services understand the boxelder bug life cycle and can apply targeted treatments to target the bugs at various stages, increasing the chances of long-term success.
Professionals also have access to specialized tools and insecticides designed specifically to manage these bugs, ensuring a more thorough and lasting solution. They can also offer advice on how to effectively eliminate boxelder bugs, thereby reducing the likelihood of recurring problems.
Get Help with Your Boxelder Bug Infestation with At Home Pros Today!
Dealing with a boxelder bug infestation can make your home feel unclean and uncomfortable. The good news is that you don’t have to tackle it alone. Whether you’re looking for long-term prevention or immediate relief, At Home Pros connects you with trusted local experts, such as Terminix and Aptive Environmental, who know how to get rid of boxelder bugs the right way.
Reach out to At Home Pros today to get in touch with a licensed pest pro in your area!
FAQs About Boxelder Bugs
Here are answers to some of the most commonly asked questions about boxelder bugs:
Can boxelder bugs survive on indoor plants or houseplants?
Boxelder bugs primarily feed on the seeds and sap of certain trees and are not known to feed on typical indoor plants. While they may occasionally crawl on houseplants, they don’t consume them or cause damage like spider mites or aphids.
Their mouthparts are adapted for piercing tree seeds and leaves, so houseplants are not a suitable food source. If you find boxelder bugs indoors, they’re usually just wandering or seeking shelter rather than feeding. Keep houseplants away from window sills and entry points where bugs might gather.
Can boxelder bugs fly, and how far can they travel?
Boxelder bugs are capable of flight, but they usually stay close to their preferred host trees or overwintering sites.
Their flights are often short-distance movements within a neighborhood or yard, helping them locate food or shelter. Although they can be carried by wind over longer distances, boxelder bugs don’t typically migrate far from areas where their host trees grow. This means that infestations tend to be localized around boxelder and maple trees.
Can artificial lights attract boxelder bugs at night?
Boxelder bugs are not strongly attracted to artificial lights like moths or some other insects. They are primarily daytime creatures that rely on warmth and food sources rather than light for navigation.
However, if they have already entered a building, they may be seen near windows or light fixtures, as these areas often provide warmth or access to exits. Using outdoor lighting thoughtfully won’t significantly increase the presence of boxelder bugs, but sealing entry points effectively is essential.
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