Length: Up to 4 cm
Colour: Black and red/orange
The boxelder bug is a type of insect native to North America. They are named for their preferred habitat of, the seeds of the boxelder tree, which includes hickory and ash trees. Adults can have wingspans around 1.8-2.2 cm wide. The adults are black with red lines on their thoraxes and abdomen, while the nymphs are orange with red markings. They have a typical “bug” shape, though they can be hard to see when hiding underneath plant leaves.
Boxelder bugs will go through three different stages in their lives: egg, nymph, and adult. The eggs are laid from April to June, generally on the undersides of branches and leaves. Nymphs hatch from July to September and progress through five molts before reaching adulthood. Adults begin laying eggs in October until the first frost, which signals winter for boxelder bugs. During winter, they hibernate as adults underneath plant bark by sealing small openings with their feces. Boxelder bugs are generally found on ash, apple, boxelder, maple, mulberry, and pear trees.
They typically only come out in the spring after the first warm days of the season. They mate shortly afterwards. They feed by sucking plant juices from leaves or fruit of plants with their short mouthparts.
The boxelder bug is not known to spread any diseases and typically isn’t a threat to humans. They do, however, bite humans and can leave small welts on the skin where they punctured it with their beaks. This can become a problem for some people who are allergic to boxelder bug saliva. Though harmful to humans, boxelder bugs do have a positive impact on the ecosystem. They are an important food source for birds, spiders and other insects which keeps their population in check.
Since they feed off plant leaves and fruit, boxelder bugs can become a problem when their population grows too large, or they decide to enter a house in search of a place to hibernate for the winter. Their size can make them difficult to get rid of, but there are steps that can be taken to keep boxelder bugs out of a house or away from plants they may want to feed on. Making sure there is no debris, branches or wood lying against the foundation of a house will reduce their chances of getting inside. Removing leaves and fruit that may be in contact with a home will also reduce the chance of boxelder bugs infesting a house. There are pesticides available to use; however, they must be used correctly and may not be necessary if steps are taken to make outside less attractive for the bugs.
The best way to get rid of boxelder bugs is to vacuum them up. They can also be swept or knocked down from plants and drowned in soapy water.