Boxelder Bugs In Utah

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Summer sunshine brings a lot of beauty and positive vibes into our Utah communities, but it also brings many tiny nuisances along with it. Boxelder bugs are known as “true bugs,” and they are often misidentified as stink bugs or ladybugs. As a state with a county named “Box Elder,” it is no surprise that these bugs are seen in large gatherings all over Utah. While they are not medically significant and will not seriously harm you, they are often dreaded for their ugly congregations, staining excrement, and foul-smelling discharge.

How To Identify Boxelder Bugs

two box elder bugs on a white background

As one of the most easily identifiable insects in Utah, boxelder bugs are likely to be spotted all summer long. The most common nickname of the boxelder bug is the “Halloween bug,” which references its unmistakable black and orange colors. Aside from its famous colors and markings, there are a few other key characteristics you can look for when trying to identify boxelder bugs.

  • Flat bodies of roughly ½ an inch in length
  • Pale black color with bright orange-to-red markings
  • Bright markings make up part of “X” shape on wings
  • Three vertical orange markings behind head
  • Long, curved antennae
  • Large red eyes, with two smaller eyes on top of head
  • Long proboscis tucked under body when not in use

How Long Do Boxelder Bugs Live?

On average, boxelder bugs in Utah live for about one year. However, adults are active for only a few days of their lives before dying, spending much of their lives developing and overwintering. Eggs are typically laid in spring and summer and take only a few days to hatch. New hatchlings are a bright red color, as they are not born with their black wings. As the young insects molt, they develop wings and become darker in color. Adults are able to fly up to two miles while looking for a source of food and shelter.

Boxelder bugs breed mainly in spring and early fall, and a single bug can breed up to three times in its life. However, most immature bugs die in late fall because boxelder bugs need to overwinter, and only the mature bugs are strong enough to survive winter conditions. Adult females that survive overwintering will lay hundreds of eggs in the springtime before the end of their short lives so the next generation can thrive.

Where Are Boxelder Bugs Found?

As their name suggests, boxelder bugs dwell in cracks in the bark of seed-bearing trees, such as boxelder trees, maple trees, and ash trees. Their diet consists almost entirely of the seed pods and leaves of these trees, which are accessed by the insect’s long proboscis. Boxelder bugs will spend the majority of their lives on the seed-bearing female trees, but they are rarely found on the male trees.

two box elder bugs climbing up a tree

Boxelder bugs will spend as much time as possible in seed-bearing trees, but they will migrate once the weather turns a bit colder. Like many true bugs, boxelder bugs can detect the smallest change in temperature, which lets them know when the harmful cold weather approaches. As temperatures get a bit too cool in the trees, these bugs will begin seeking out warm, sunny surfaces. As fall sets in, boxelder bugs are notorious for getting into cracks and crevices of homes for overwintering.

swarm of red box elder bugs on the foundation of a home

Once a reliable source of food is found, boxelder bugs will not stray far. You are most likely to see boxelder bugs gathered in large clusters on the sunny side of buildings near seed-bearing trees. This allows the bugs to soak in all the sunlight they require while still having nearby access to the trees and/or fallen seed pods. From there, the bugs will start to look for small entry points into your home when the temperatures begin to drop, such as underneath doors, in between side paneling, through vents, etc.

Are Boxelder Bugs Harmful?

Boxelder bugs do not sting or transmit disease, leading many people to label them as “harmless.” While it is true that these insects do not pose a significant health risk to humans, they are still, at best, a nuisance on your property. Below are just a few of the annoyances caused by boxelder bugs.

Boxelder bugs…

  • gather in large, unsightly clusters against the side of your house.
  • can bite for defensive reasons, though reports are rare.  
  • release a foul stench when touched.
  • will ravage fruits of other trees if their desired maple trees are not present.
  • can quickly invade a home in large numbers.
  • produce a hideous excrement that will stain your home’s interior.

How To Stop Boxelder Bugs

Preventing boxelder bugs from congregating on and around your home is always the best way to handle these insects. Unfortunately, many people live with boxelder bugs all winter and have no idea until the bugs begin to emerge in spring. Walls and attics make perfect environments for the bugs to overwinter, but you may not even know they are there until the weather gets warmer and these pests become active again.

box elder bug pest control

Preventive Treatments

Stopping these pests from getting into your home is always easier than trying to remove them. Keep the following guidelines in mind this season when it comes to protecting your home from boxelder bugs.

  • Remove or cut back female boxelder trees.
  • Do not plant maple/boxelder trees.
  • Mow frequently and/or pick up fallen seed pods immediately.
  • Seal or caulk any cracks along the perimeter of your home.
  • Fill cracks in the concrete around your home and yard.
  • Repair holes in screen doors and windows.
  • Install mesh covers over vents.
  • Install door sweeps and weather stripping.
  • Call a professional pest control service.

Curative Treatments

If preventive measures fail and you are forced to deal with a boxelder bug invasion in your home, remembering the guidance below could make the difference between a successful bug removal or a much worse pest problem.

  • Spray large clusters of bugs off your home’s exterior with a power washer or hose.
  • Mix water and hand soap in a spray bottle to use against any bugs in your home.  
  • Vacuum the bugs up, seal the vacuum bag, and dispose of the bag away from your home.
  • DO NOT squish boxelder bugs; they will leave horrible stains inside your home and release an offensive odor that will only attract more boxelder bugs.
  • Call Holmes Lawn & Pest for more information on pest control in Utah. Dealing with boxelder bugs can be a tricky problem, but we are here to help!

We hope you enjoyed our blog on boxelder bugs in Utah. If you are finding brown recluse spiders in your home or around your yard, check out this article to learn everything you need to know on this potentially dangerous arachnid.

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