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Boxelder Bugs
Boisea trivittata (Say)
Boxelder Bugs Identification
Pest Stats
Color
Black with reddish or orange markings on dorsum
Legs
6
Shape
Elongate-oval, somewhat flattened with head narrower than pronotum
Size
1/2” (11-14 mm)
Antennae
Yes
Region
All
What Do Boxelder Bugs Look Like?
Boxelder bugs are black with reddish or orange markings on their back. Adult boxelder bugs have a body shape that is a somewhat-flattened and elongated oval and is about half an inch long. They have six legs and two antennae that are typically half of their body length. Nymphs look similar to adults but lack wings and are bright red in color.
Signs of an Infestation
Boxelder bugs generally become a problem when they invade homes, sheds and garages in the fall and when they emerge in the spring. Like many overwintering pests, homeowners may see evidence of these bugs as the winter ends and they leave their overwintering site to go back outdoors.
Boxelder Bug Photos
Boxelder Bugs Prevention
How To Get Rid Of Boxelder Bugs
In order to prevent boxelder bugs from invading homes, repair holes in window and door screens, seal cracks and crevices with a good quality silicone or silicone-latex caulk and install door sweeps to all exterior entrances.
When getting rid of boxelder bugs that have already entered a home or building, no attempt should be made to kill them in wall voids because dead insect bodies can attract dermestid beetles (larder beetles, carpet beetles, etc). Experts recommend waiting until summer when all live overwintering adults are out of the wall voids. To provide temporary relief during this time, consider using a vacuum cleaner to get rid of the boxelder bugs. The bag should be removed to prevent the bugs from escaping. Then, seal up any entryways into the living space – window pulleys, window and door frames, baseboards, etc. – to prevent a future infestation. For electrical outlets, switch boxes, heating ducts and return air vents, remove the coverplate, seal and replace. For light fixtures and ceiling fans, remove the fixture to its base plate, seal and replace.
If a boxelder bug infestation is suspected, a licensed pest control professional should be contacted to evaluate and assess the problem.
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Do Boxelder Bugs Bite?
Boxelder bugs are not known to bite, but their piercing-sucking mouthparts can occasionally puncture skin, causing a slight irritation and producing a red spot similar to a mosquito bite.
Boxelder Bugs Education
Habits
Overwintering adult boxelder bugs emerge from hibernation in late March to early April when the boxelder buds open. During this time, the adults leave their overwintering sites to return to their host trees for the warmer months. They first feed on fallen boxelder seeds and later move to the female boxelder trees or maple trees where they eat newly developing leaves. Occasionally, boxelder bugs will feed on the fruits of plum and apple trees.
The females lay clusters of straw-yellow eggs on stones, eaves, grass, shrubs and trees – especially in the bark crevices of boxelder trees. The eggs turn red as the embryos develop and hatch about two weeks later. The nymphs feed on fallen boxelder seeds and later on new leaves. There are two generations per year in the warmer regions of the United States.
In the fall, boxelder bugs become gregarious and congregate on the south side of rocks, trees and buildings where the sun hits. After large masses gather, they migrate to nearby buildings or homes to overwinter. These pests tend to hide in small cracks and crevices in walls to insulate themselves from the cold winter temperatures.
Threats
Inside, boxelder bugs are primarily a nuisance pest, however their fecal material can cause a red stain on curtains, drapes, clothing, etc. When crushed or handled roughly, boxelder bugs can also produce a strong, disagreeable odor.
Habitat
In autumn, boxelder bugs become gregarious and congregate on the south side of rocks, trees and buildings where the sun hits. After large masses gather, they migrate to nearby buildings or homes to overwinter. These pests tend to hide in small cracks and crevices in walls to insulate themselves from the cold winter temperatures. In late March to early April, adults leave their overwintering sites to return to their host trees for the warmer months.
Boxelder bugs are not known to bite, but their piercing-sucking mouthparts can occasionally puncture skin, causing a slight irritation and producing a red spot similar to a mosquito bite. When crushed or handled roughly, boxelder bugs may leave a reddish orange stain from their fecal material that can result in discoloration of curtains, drapes, clothing, etc.
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