Boxelder bugs are a common sight in areas where boxelder trees are found, often taking up residence in homes and buildings.
While their appearance may be cause for concern to some, rest assured that these bugs are actually quite harmless.
Unlike other insects such as mosquitoes or ticks, boxelder bugs do not bite humans or animals.
They are part of the Rhopalidae family, closely related to scentless plant bugs, stink bugs, and cicadas, which possess piercing and sucking mouthparts.
Instead of feeding on blood, boxelder bugs use their mouths to feed on boxelder tree seeds and leaves.
Their presence can be a nuisance due to large infestations and the odor released when crushed; however, they do not pose a threat to human health or safety.
So, the next time you encounter a boxelder bug, there’s no need to worry – they won’t bite!
Boxelder Bugs: An Overview
Boxelder bugs, scientifically known as Boisea trivittata (and closely related to Boisea rubrolineata), are a species of true bugs belonging to the Rhopalidae family.
Found in North America, these insects are notable for their distinct black coloring and red markings.
Unlike some other pests, boxelder bugs are generally considered nuisance pests around homes with nearby plantings of boxelder trees.
Although they don’t typically cause significant damage to plants or homes, their feces can stain light-colored surfaces.
Key Characteristics
- Dark gray to black, with red stripes
- Oval shape
- Three red stripes on the thorax
- Red eyes
- Length: about ½ inch
- Wings outlined in red
- Belongs to the same family as stink bugs and cicadas
Boxelder bugs have piercing and sucking mouthparts. They don’t sting or transmit diseases, and they rarely bite, except for defensive purposes.
These insects display several developmental stages throughout the summer, with nymphs being conspicuously bright red.
Do Boxelder Bugs Bite?
Boxelder bugs (Boisea trivittata) are commonly found on boxelder trees and are generally considered nuisance pests.
While they possess mouthparts called proboscis for piercing and sucking, their primary purpose is to feed on plant matter rather than biting humans or animals.
Although boxelder bugs are mostly harmless, there have been rare reports of defensive biting in response to threats.
Unlike a mosquito bite, which can cause irritation or transmit diseases, a boxelder bug bite is not known to cause any significant harm or carry diseases.
Their main defense mechanism includes producing a foul-smelling and distasteful liquid to deter predators, rather than biting or stinging like some other insects.
They are not considered poisonous, and the risk of experiencing vomiting or serious irritation from a boxelder bug bite is extremely low.
In conclusion, boxelder bugs are not known for biting humans or animals, and any potential bite would be very rare and mild compared to other insects like mosquitoes.
Here’s a brief comparison table of Boxelder Bug vs. Mosquito bites:
To summarize:
- Boxelder bugs are harmless and unusual biters
- Mouthparts are designed for plant feeding, not people or animals
- Biting is not their primary defense mechanism
Boxelder Bugs’ Habitat and Host Trees
Boxelder bugs are a type of insect found primarily in North America.
Their habitat mainly consists of areas with boxelder trees, with seeds being their primary food source.
They can also live in other trees, such as(maple, ash, and fruit trees like apple and pear) which are often found nearby boxelder trees.
Boxelder bugs prefer sunny locations. They tend to congregate on:
- Rocks
- Buildings
- Tree trunks
- Leaves
These insects have six legs and two antennae that help them explore their surroundings.
There are several types of trees that serve as host trees for boxelder bugs. Some common species include:
- Boxelder (Acer negundo)
- Maple (Acer spp.)
- Ash (Fraxinus spp.)
- Plum (Prunus spp.)
In the fall, boxelder bugs not only feed on seeds but also tree sap, leaves, and fruits such as apples and pears.
They are an essential part of nature as pollinators for these trees, helping the plants produce seeds and fruits.
The location range is extensive, from Eastern Nevada to the Midwest and other parts of eastern North America.
Preventing and Managing Infestations
Boxelder bugs can become a nuisance pest during the colder months as they seek shelter indoors. Preventing and managing infestations involves simple, non-chemical methods.
Firstly, seal potential entry points:
- Caulk cracks in walls, windows, and vents.
- Install door sweeps on exterior doors.
- Repair window and door screens.
Maintaining cleanliness can also help:
- Vacuum frequently to remove live bugs.
- Clean up any feces, which can cause stains and smell.
Be observant for overwintering swarms and promptly address any sightings. In case of a severe infestation, consider using pesticides. However, be aware of their drawbacks:
- May harm non-target organisms, including natural predators.
- Overuse can lead to pesticide resistance in bug populations.
Introduce natural predators like beetles to control boxelder bugs outdoors.
Keep in mind that while boxelder bugs may cause slight irritation, they are not a true bug and do not bite.
Myths and Misconceptions about Boxelder Bugs
1. Myth: Boxelder bugs are harmful pests that destroy plants.
Fact: While boxelder bugs feed on the seeds and leaves of boxelder trees, they generally do not cause significant damage to these trees or other plants. They are more of a nuisance pest than a destructive one.
2. Myth: Boxelder bugs bite humans frequently.
Fact: Boxelder bugs are not known for biting humans. While they have mouthparts that can pierce, they typically use them to feed on plant matter. Rare instances of defensive biting have been reported, but they are not common.
3. Myth: Boxelder bugs transmit diseases to humans.
Fact: There is no evidence to suggest that boxelder bugs transmit diseases to humans. They are not vectors for any known pathogens.
4. Myth: Boxelder bugs are the same as stink bugs.
Fact: While both boxelder bugs and stink bugs belong to the order Hemiptera and can release unpleasant odors when threatened or crushed, they are different species with distinct behaviors and appearances.
5. Myth: Boxelder bugs infest homes year-round.
Fact: Boxelder bugs typically seek shelter indoors during the colder months to overwinter. They are not usually active inside homes during the warmer months.
6. Myth: All boxelder bugs are the same.
Fact: There are different species of boxelder bugs, with the Eastern Boxelder Bug (Boisea trivittata) and the Western Boxelder Bug (Boisea rubrolineata) being the most common.
7. Myth: Boxelder bugs are only found near boxelder trees.
Fact: While boxelder bugs are commonly associated with boxelder trees, they can also be found near other trees like maple and ash.
8. Myth: Pesticides are the only way to control boxelder bug infestations.
Fact: While pesticides can be effective, there are several non-chemical methods to manage and prevent boxelder bug infestations, such as sealing entry points, vacuuming, and maintaining cleanliness.
Conclusion
Boxelder bugs, commonly found in proximity to boxelder trees, are often mistaken for pests due to their tendency to invade homes in search of warmth.
However, these insects are largely harmless, posing no threat to human health or property. Unlike some other insects, they do not bite humans or animals.
Their primary diet consists of boxelder tree seeds and leaves. While they can become a nuisance, especially when they gather in large numbers, understanding their habits and characteristics can help in managing and preventing infestations.
It’s essential to differentiate boxelder bugs from other similar-looking pests, as the approach to control and potential risks may vary.
Footnotes
Reader Emails
Over the years, our website, whatsthatbug.com has received hundreds of letters and some interesting images asking us about boxelder bugs. Scroll down to have a look at some of them.
Letter 1 – Boxelder Bug Nymphs
Subject: Red and purple beetle
Location: SE Michigan
June 25, 2016 4:48 pm
Hi bugman!
I just noticed thousands of these guys hanging out in my backyard mostly around decorative grass and dry whirlybirds. They vary in size and amount of yellow and seem to like to clump together.
Signature: Lisa M
Dear Lisa M,
These are immature Eastern Boxelder Bugs, Boisea trivittata. Adults are winged. Both adults and nymphs form large aggregations leading to popular names like Democrat Bugs or Populist Bugs.
According to BugGuide they feed on the seeds of the following trees: “Acer grandidentatum (Bigtooth Maple), A. negundo (Boxelder), A. saccharinum (Silver Maple), A. buergerianum (Trident Maple), and Sapindus saponaria (Soapberry).” You must have a nearby maple tree.
Boxelder Bugs do not harm the trees and they are not dangerous, but they can be a nuisance if they are too plentiful.
Letter 2 – Boxelder Bug Aggregation
what are these in such a big cluster?
Sorry this is not a closeup of one or two beatles but I thoght you might be able to ID then because of their marking,,,,,,,,Thanks
Tim Knight
Hi Tim,
Excellent photo of a Boxelder Bug Aggregation.
Letter 3 – Boxelder Bug Aggregation
What’s this Bug?
My ex wife has discovered a lot, and I do mean a lot, of these bugs on the side of her house. There are literally hundreds of them. It appears as if the younger bugs have red bodies and as they mature they grow black wings. Any idea what they are?
Thanks,
Stephen Bland
Hi Stephen,
We get many letters regarding large aggregations of Boxelder Bugs. We have also gotten reports that spraying them with soapy water will kill them.
Letter 4 – Boxelder Bug Aggregation
Red Bug
Hello, Daniel & Lisa!
I thought I would inquire about a picture I sent a few days ago about the red bugs who have invaded our lawn. I’ve not seen anything on the site, just thought I’d ask if you knew what they are and what they do? 😉 Thanks,
Darla Tanner
Hi Darla,
Now that you have finally attached a photo that arrived, we have lost your original letter. Your photo depicts an aggregation of Boxelder Bugs. Often they form large masses of adults and juveniles, especially in the autumn.
In recent months, due to our site’s popularity, we have been forced to run ads, and help with Boxelder Bugs are always present among the ads.
Letter 5 – Boxelder Bug Nymph
what is this beetle?
Hello,
I have hundreds of these little red and black beetles in my yard. Can you identify what they are? Are they harmful to my lawn? I live in Palm Harbor, Florida, near Tampa Bay. Thanks very much for your help. Best regards,
Roger Leighton
Hi Roger,
No photo arrived, but we are guessing probably Boxelder Bugs or other hemipteran.
My apologies, I included two photos in my last email, strange they didn’t come through. I will try to attach the photos differently. Close guess, these beetles do look like boxelder bugs in shape but seem to have much more red to them. Let me know if the photos made it or not this time. And thanks again for your time. Regards,
Roger
Hi again Roger,
This is a Boxelder Bug nymph. The wings of the adults cover the red coloration on the abdomen.
Letter 6 – Boxelder Bug Aggregation
What is it ?
I have been seeing these bugs on the walking trail at different times during the year. Usually they are swarming on a nearby Locust Tree, but now that the trail has erected a sign with glass panels, they are swarming on it.
Also inside the glass. They are about the size of a Lightening Bug, thin flat body, red wings. They CAN fly, but not too far. Are they any danger to the wood. ? I will attach a pic. Thanks
Joe “Pip” Betz
Hi Joe,
It seems we chose wisely when we decided to make the Boxelder Bug our featured Bug of the Month for November, but judging by the number of letters, our readership is having a disconnect when it comes to identifying their own sitings.
We had three images posted on our homepage at the time your letter was submitted, and your letter will make four. There is much information online about Boxelder Bugs.
Letter 7 – Boxelder Bug Aggregation
Curious – Red Bug – Beetle?
Hello,
I ran across your site while investigating what this bug may be. I live Eastern Ontario (Ottawa), Canada. These bugs have been here since June, Usually clump together on wood. But lately they have been spreading out, on leaves of plants and my covering my basement windows.
They are pretty, but I am wondering what they are and if I should be worried. I appreciate any help you may have to offer. I have attached 2 photo’s. One of them clumped together and another on their own. Thank you in advance
Christina
Hi Christina,
We try to keep a photo of Boxelder Bugs on our homepage, especially in the autumn when they become more noticeable and sometimes seek shelter inside homes.
They are Scentless Plant Bugs that form large groupings of the red wingless nymphs along with the black and red winged adults. These groupings are known as aggregations. There are several products as well as numerous websites advertising methods to rid your yard of Boxelder Bugs.
Letter 8 – Boxelder Bug: Wrongfully Maligned???
Another Boxelder Question
I’m shocked to find you advocating the extermination (via a mild solution of detergent and water) of Boxelders without explaining WHY they should be killed. This is even more surprising after reading your reactions to all the carnage photos sent to you.
For some reason, the poor little (seemingly) harmless Boxelder just isn’t a worthy creature. I think I’ve read through all the postings regarding Boxelders and I haven’t found (unless I missed it) a good reason for killing them. Please enlighten me. Though I don’t think another photo is needed, I’ve attached one. (Sorry I couldn’t get him to smile…)
Dan
Hi Dan,
Your letter has given us pause to think about this. Here is what BugGuide has to say: “Adults take plant juices from maples, fruit trees, sometimes nectar. Nymphs feed on seeds, also dead insects, sometimes cannibalize other nymphs as they molt. ” and “Considered a nuisance when it invades houses.
Not an economically important pest, as its main food source (Boxelder) has little or no commercial value.” So, Boxelder Bugs are a nuisance, but are not a particular threat. We should perhaps revisit our advise on how to control them. We have never endorsed wholesale extermination of the species.
People whose lives are impacted by population explosions of Boxelder Bugs, especially when they invade the home, might want a environmentally safe means of control. Though we tolerate insects in our home, we would not want to be invaded by 1000’s of Boxelder Bugs, and if that happened, we might resort to some means of control.
Once again, for clarification, we have never endorsed wholesale extermination, but perhaps our advice to use soapy water should be reserved for otherwise uncontrollable numbers.
Letter 9 – Boxelder Bug Nymph: Democrat Bugs
Red bug thing
Location: Austin, TX
March 30, 2011 12:56 pm
Can you please help me identify? We live in Austin, TX and these seem to be infesting the yard and wooded areas… clustered in large groups.
Signature: Sarah Warland
Hi Sarah,
This is an immature Eastern Boxelder Bug nymph, Boisea trivittata. Adults and nymphs can become a nuisance because they often form large aggregations and they often enter homes in the fall where they hibernate until warm weather returns.
They will not harm the home, but most folks do not want to share their dwellings with great quantities of insects. They feed upon the seeds of boxelder and other maples, so they also do not have a direct negative impact on the plants themselves.
They are benign insects, but again, they are considered a nuisance since they can become quite plentiful. Depending upon your political affiliation, you may or may not find it amusing that they are also commonly called Democrat Bugs.
Cool! Thanks so much… we do seem to be infested but I am glad to know they are not harmful.
Much appreciated!!
Letter 10 – Boxelder Bug aggregation
Subject: Little red bugs
Location: Hamilton Ontario Canada
September 22, 2012 9:39 am
Hi, we found a group of these little red/orange bugs recently and have no idea what they are.
The scale doesn’t show in the photos, but they’re about 1/4” to a max of 1/2” long.
They were found in an outdoor area, around an old storage trailer. As the pictures show, they seemed to congregate together, though they were spread across a large area.
We are in Hamilton Ontario (southwestern shore of Lake Ontario), and the weather was sunny and warm. The pic was taken a few days ago.
Any idea what these guys are?
Signature: Allan
Hi Allan,
A similar aggregation of Eastern Boxelder Bugs, Boisea trivittata, is currently featured on our homepage banner. Because they form such large aggregations, Boxelder Bugs are also called Politician Bugs, Populist Bugs or Democrat Bugs.
