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Learn about plant insect control for commercial premises.
If you’ve seen small, dark insects clustering around your windows or the sunny sides of buildings, you may be dealing with boxelder bugs. Read on to learn how to recognize them, where they live, and what you can do to keep them under control.
What are boxelder bugs?
The boxelder bug (Boisea trivittata) is a common pest often found around homes and trees, especially in warm, sunny areas. While they don’t cause major structural damage, their presence in large numbers can become a nuisance. These insects are known for gathering on walls, windows, and siding in the fall as they look for warm places to overwinter.
Key characteristics
The following characteristics can help with boxelder bug identification.
- Adult boxelder bugs are about half an inch long with a flat, oval body.
- Their black bodies are marked with red or orange lines along the wings and thorax (middle body segment).
- Nymphs are bright red and wingless but share the same body shape as adults.
- They have six legs, long antennae, and piercing mouthparts used for feeding.
The boxelder bug life cycle begins when adults emerge from overwintering sites in spring. They lay small, red eggs on trees, leaves, and bark. Within about two weeks, the eggs hatch into nymphs which go through several growth stages before becoming adults.
Adults can live for several months and often produce more than one generation per year in warmer climates. As they complete each phase of development, their behaviors change from feeding on plants to seeking shelter indoors as temperatures drop.
The boxelder bug habitat typically includes areas near boxelder trees, as well as maples and ash trees. These insects are especially drawn to seed-bearing female boxelder trees. During cooler months, they move toward buildings and homes, finding cracks or gaps to shelter in.
The boxelder bug diet, unsurprisingly, mainly consists of the seeds of boxelder and maple trees. They may also feed on the juices of leaves, twigs, and developing fruit. Although their feeding rarely kills trees, it can cause discoloration or minor damage to leaves and fruit.
You’re likely to encounter boxelder bugs across much of the United States, though the highest populations are found in the central and eastern regions where boxelder and maple trees are widespread. They are particularly common in the Midwest and parts of the South but can also appear in western states where suitable trees grow.
Managing boxelder bugs
Whether they’re clustering on sunny walls or finding ways inside, managing boxelder bugs requires both prevention and control. The following sections explain how to stop them from entering in the first place and what to do if they’ve already made themselves at home.
Preventing boxelder bug infestations
- Seal up gaps, cracks, and vents around your home to block entry points.
- Keep windows and doors fitted with tight screens.
- Remove boxelder trees near high-traffic areas or manage seed production where possible.
- Clear fallen leaves and debris that may attract overwintering insects.
Taking steps like these can reduce the chances of a boxelder bug infestation, especially during the fall when they seek shelter.
Effective boxelder bug control methods
Minor infestations can sometimes be managed with vacuuming and removing visible clusters outdoors. For larger infestations, or to address the root cause of an infestation, professional help is sometimes needed.
Our technicians can inspect your property, locate entry points, and recommend targeted treatments to help reduce the problem. With expert guidance, you can protect your property and minimize the risk of future infestations.
Frequently asked questions
Adult boxelder bugs have black bodies with bright red or orange markings along their wings and thorax. They measure about half an inch in length and have six legs with long antennae. Nymphs are smaller and bright red before developing wings as they mature.
Boxelder bugs are native to North America and commonly found near boxelder, maple, and ash trees. In the fall, they leave trees to look for warm, dry places to spend the winter. Homes, sheds, and cracks in siding are typical overwintering sites.
Boxelder bugs are most active in the warmer months of spring and summer when feeding and breeding occur. As temperatures drop in fall, they begin searching for shelter. Activity decreases through winter until they re-emerge in spring.
Boxelder bugs do not bite or sting and are not known to spread diseases. They may cause mild skin irritation if handled or crushed, but this is uncommon. They’re more of a nuisance pest rather than a health risk.