Are Boxelder Bugs Dangerous? Uncovering the Truth

Boxelder bugs are a common sight in many parts of North America, particularly during the warmer months. These insects can often be found near boxelder trees, as well as other tree species like ash and maple.

While they may seem like a potential threat, it is important to understand their behavior and impact on humans and the environment.

These bugs belong to the Rhopalidae family, which is closely related to Coreidae, a group known for emitting unpleasant odors when alarmed. However, they are considered scentless plant bugs and do not emit strong smells.

Both boxelder bugs and invasive brown marmorated stink bugs can be seen congregating on walls during the early fall, in search of warmth and shelter.

Despite their occasional large numbers, they are generally harmless to humans and do not cause structural damage to buildings.

Although boxelder bugs are not considered dangerous, they can sometimes be a nuisance due to their tendency to gather in large numbers. In some cases, they may also feed on the developing fruits of various trees, causing minor damage.

It is important to note that these insects pose no significant threat to humans, and their presence should not cause undue concern.

 

What Are Boxelder Bugs

Boxelder Bug Identification

Boxelder bugs are small insects with a striking black and orange color pattern on their bodies. They have an elongated, somewhat oval shape and measure about ½ inch in length. Some key features to help identify boxelder bugs include:

• Black body with orange or red markings
• Six legs
• Oval-shaped wings covering the abdomen
• Part of the Rhopalidae family

Life Cycle

Boxelder bugs go through various life stages, from egg to nymph, and finally, adults. The nymphs are smaller and have a bright red color, while the adults have a more distinct black and orange pattern on their bodies.

During the summer, you can observe boxelder bugs in all stages of development. As they progress through their life cycle, their coloration and size change, making it easier to identify the different stages.

Are Boxelder Bugs Harmful or Dangerous?

Boxelder Bugs and Humans

Boxelder bugs are a harmless nuisance around homes and buildings, particularly near boxelder tree plantings. While they can be an annoyance, they do not pose any significant threats to humans.

They are not known to bite or sting, making them safe to coexist with. However, they can become a sizable annoyance as they congregate in large numbers around buildings and homes.

 

Effects on Pets and Animals

Boxelder bugs do not pose a direct danger to pets or animals. Even when present in large numbers, these insects do not cause harm to animals or transmit diseases. It’s important to note that:

• Boxelder bugs don’t bite or sting pets or animals
• They’re not known to carry or transmit diseases to pets or animals

Comparison Table: Boxelder Bugs versus Dangerous Insects

Characteristics	Boxelder Bugs	Dangerous Insects
Bite or Sting	No	Yes
Harm to Humans	No, only a nuisance	Yes, can cause pain and discomfort
Harm to Pets/Animals	No	Yes, can harm or cause distress
Disease Transmission	No	Yes, can transmit various diseases

Damage Possibilities Caused by Boxelder Bugs

Potential Home Damage

Boxelder bugs, while not directly harmful to humans, can cause some minor damage in homes. They are known to produce liquid feces that leave behind stains on walls, curtains, and drapes when crushed.

Additionally, their presence in large numbers can be a nuisance as they often shelter in eaves and windowsills.

Agricultural and Property Effects

Boxelder bugs can have negative impacts on trees and crops. For example, they can feed on developing leaves, causing distortion or yellowing of the foliage. Here are some potential damages to agricultural properties:

• Tree damage: Their feeding habits may also lead to damage to flowers, tender twigs, and seeds of boxelder trees.
• Damage to fruits: In heavily infested areas, boxelder bugs may attack fruits raspberry, and strawberry plants, causing possible harm².

However, it’s important to note that the plant damage they cause is generally not considered serious.

Comparison of Boxelder Bug Damages

Type of Damage	Severity	Examples
Home & Interior	Low	Stains on walls, curtains, drapes
Agricultural (trees, fruits)	Low	Distortion of foliage, and fruit harm

Overall, boxelder bugs are more of a nuisance than a serious threat to homes or agricultural properties. By practicing proper home maintenance and identifying potential infestations early on, their impact can be minimized¹³.

Boxelder Bug Habits and Preferences

Feeding Patterns

Boxelder bugs mainly feed on boxelder trees by sucking sap from leaves, tender twigs, and developing seeds. They can also occasionally feed on ash trees, maple trees, and the fruits of raspberry and strawberry plants.

• Preferred food: Boxelder trees
• Secondary targets: Ash trees, maple trees, raspberry, and strawberry fruits

Preferred Environments

These bugs are known to congregate in large numbers on the sunny side of trees, buildings, and walls during fall. They prefer sunny locations and tend to overwinter in protected dry places, such as wall voids, attics, and basements.

• Outdoor environments: Trees, buildings, walls (particularly the sunny side)
• Indoor environments: Wall voids, attics, basements

Boxelder Bugs’ Relation to Other Insects

Boxelder bugs belong to the same family as stink bugs, cicadas, and other insects with piercing and sucking mouthparts. However, unlike their relatives, these bugs are scentless and considered harmless nuisances.

Comparing Boxelder Bugs to Stink Bugs:

Feature	Boxelder Bugs	Stink Bugs
Family	Rhopalidae	Pentatomidae
Feeding	Sap from leaves, twigs, seeds	Sap from leaves, twigs, fruits
Smell	Scentless, odor when crushed	Strong odor when disturbed

Preventing Boxelder Bug Infestations

Sealing and Securing Homes

To prevent boxelder bugs from entering your home:

• Seal cracks and crevices with caulking
• Install door sweeps and use weather stripping around windows and doors
• Ensure screens on windows and vents are in good condition

For example, you may discover a gap between your foundation and siding. Use caulking to seal the gap and deter boxelder bugs from entering.

Pros of securing homes:

• Reduces boxelder bug infestations
• Lesser need for pest control treatments

Cons of securing homes:

• Can be time-consuming and expensive

Landscaping Tips and Best Practices

Proper maintenance of the outdoor area surrounding your home can help in minimizing boxelder bug infestations:

• Remove boxelder trees or limit their growth near your home
• Clear debris, like leaf litter, that can provide shelter for the bugs
• Trim branches providing contact or access to your home’s structure

A comparison of different landscapes:

Landscaping Feature	Attracts Boxelder Bugs	Reduces Boxelder Bug Infestations
Boxelder Trees	✓
Tidy Garden		✓
Tree Branches Touching the House	✓

Keep in mind that while landscaping can help, it may not completely prevent boxelder bug infestations, as they can still fly and find alternative ways to enter your home.

Pest Control

As a last resort, you can consider hiring a professional pest control service to help manage and prevent boxelder bug infestations.

However, this is not a preferred method, as boxelder bugs are generally harmless and considered a nuisance rather than a harmful threat.

It’s recommended to focus on sealing and securing your home and maintaining a tidy landscape in order to prevent them in the first place.

Controlling Boxelder Bug Populations

Natural and Chemical Pesticides

Boxelder bugs often become a nuisance around homes and buildings near boxelder, ash, and maple trees. To control these pests, you can use natural methods, such as:

• Soapy water: Mix a few drops of dish soap with water in a spray bottle, and squirt it directly onto the bugs.
• Neem oil: Applying neem oil as a natural pesticide can deter boxelder bugs from infesting your home.

For severe infestations, chemical pesticides may be necessary. These can include:

• Pyrethrin-based insecticides: Effective against a variety of pests and generally safer for humans and pets.
• Synthetic insecticides: Stronger options like permethrin and cyfluthrin should be used cautiously to avoid harm to beneficial insects.

Mechanical Control Methods

Besides pesticides, several mechanical methods can help control boxelder bug populations:

• Vacuuming: A vacuum cleaner with a hose attachment can help to remove individual bugs or small groups found inside your home.
• Physical barriers: Seal cracks and gaps in your home’s foundation to prevent bugs from entering.

Some key features of each control method are:

Control Method	Pros	Cons
Natural Pesticides	Eco-friendly, less harmful to humans and pets.	May not be as effective for large infestations.
Chemical Pesticides	Effective for large infestations.	Can harm beneficial insects, and risk of chemical exposure.
Mechanical Methods	Non-toxic and safe for the environment.	Requires more effort and may not eradicate an entire infestation.

Remember, when handling boxelder bugs, it’s important not to crush them, as they can release a bad odor. Utilize these control methods to safely keep their populations at bay.

Conclusion

In conclusion, while boxelder bugs may seem like a potential threat due to their occasional large numbers and gathering tendencies, they pose no significant danger to humans.

However, they do cause damage to trees and other agricultural properties. With proper home maintenance and landscape management, you can keep these bugs at bay.

Understanding their behavior and taking preventive measures can ensure peaceful coexistence with these unique and colorful insects.

The next time you encounter these curious creatures remember that they are harmless and are a part of our natural ecosystem.

Footnotes

1. Penn State Extension ↩ ↩² ↩³
2. Extension ↩ ↩²
3. UMN Extension ↩

Reader Emails

Over the years, our website, whatsthatbug.com has received hundreds of letters and some interesting images asking us about these insects. Scroll down to have a look at some of them.

Letter 1 – Eastern Boxelder Bugs emerge from hibernation

what bug is this?
Location: Sunderland, Massachusetts
April 3, 2011 10:55 am
hi there, we just found a swarm of these bugs trying to invade our mother’s house. We’ve only seen them around here recently, but don’t know what they are.

They appear to have nested in a crack in the foundation under her front door. While most are outside have worked their way into the house.

they are just under a half-inch long. Their body is black. they have a red back, and when the wings are closed, a red stipe is still visible between the folded wings. Although they can fly, most are walking around on the walls, doors, etc.

Can you please let us figure out what kind they are?
thank you
Signature: mc

Dear mc,
You have an aggregation of Eastern Boxelder Bugs that have just emerged from hibernation.  When the weather begins to cool, Eastern Boxelder Bugs seek shelter and they have adapted to cohabitation with humans. 

Cracks in foundations are frequently used as an entry to homes where the Eastern Boxelder Bugs remain dormant until warm sunny spring days.  Then they emerge and sun themselves on southern-facing exposures. 

Eastern Boxelder Bugs are quite benign, however, they can become an annoyance if they are plentiful.

Letter 2 – Eastern Boxelder Bugs

red bugs
Location: Wills Point – East Texas
May 11, 2011, 4:20 pm
These bugs appeared this year. They have made their home in the mulch that surrounds my pool. I wanted to know if you could tell me any information about these bugs.

I’d like to know if I need to get rid of them to protect my kids and animals or if they were harmless.

Signature: Michelle

Dear Michelle,
You have immature Boxelder Bugs and they are perfectly harmless, though they are frequently considered an annoyance because they can appear in prodigious numbers. 

You can search through our archives where there are over twenty-five postings of Boxelder Bugs or you may also check BugGuide for additional information.

Letter 3 – Eastern Boxelder Bugs

Subject: Red Beetle type of bug
Location: Holland NY
August 20, 2012, 5:32 pm
We have an infestation on some of our trees with this bug. What is it and how do we get rid of it?
Signature: Thank You B. K Holland NY

Dear B. K Holland NY,
You have Eastern Boxelder Bugs, Boisea trivittata, which are sometimes called Democrat Bugs in the midwestern states.  They are benign creatures that might become a nuisance if they are numerous as they sometimes enter homes to hibernate. 

They are one of our most frequent identification requests, so we often tag them with Top 10, but we have not posted a good aggregation image in some time.  We do not give extermination advice.

Letter 4 – Eastern Boxelder Bugs reported on bird and animal droppings

Subject: Box Elder Bug Aggregation?
Location: Lake County, IL
September 25, 2012, 1:03 pm
Thank you for this great site!
Recently, I found piles, and individuals, of these red and black bugs on a trail around the Volo Bog (IL).

They were most often seen en masse on bird/animal droppings.
Signature: LSchiele

Dear LSchiel,
Though we have no dearth of new postings of Eastern Boxelder Bugs on our website at the moment, we are fascinated by your report that you found them feeding on bird and animal droppings. 

They were most likely extracting fluids since they have mouths designed for sucking.  Your photograph includes a seed that appears to be a maple “helicopter” and that would indicate that the typical food of the Eastern Boxelder Bug is present in Volo Bog.

Letter 5 – Western Boxelder Bugs

Update:  February 29, Leap Day 2016
Upon linking to this old posting from British Columbia, we realized these are Western Boxelder Bugs, Boisea rubrolineata, NOT their eastern relatives.

Subject: Red Bug ID…Please
Location: Golden, BC., Canada
September 20, 2013, 3:51 pm
These bugs seem to have appeared very quickly and I have never seen them in this area before. I need to know if they are harmful to my family or my home. They also seem to be multiplying very quickly.

Any info you may have would be greatly appreciated. Thank you.
Signature: Claude Poirier

Hi Claude,
Eastern Boxelder Bugs, or Democrat Bugs as they are also called in parts of the midwest south of the border from you, do not pose any threat to your family or home, but they can become a nuisance if they get plentiful, especially since they have a habit of entering homes to hibernate when the weather begins to cool.

Letter 6 – Eastern Boxelder Bugs hibernating in home

Subject: Bug identification
Location: Upstate NY Catskill Mountains
February 23, 2017 11:05 am
In the past 2 weeks, I’ve noticed these bugs crawling around in broad daylight. They resemble a roach but my husband swears it’s not. I see about 10 on any given day.

They are seen sporadically anywhere, kitchen floor, living room floor, etc. Never seen on countertops but the thought of bugs in my home gives me the creeps. Could you please help me out here and identify this bug?

It started about 2 weeks ago, as the weather has been warming up here in the Catskill Mountains, Upstate, NY.
Signature: Marie

Subject: Bug identification
Location: Upstate NY Catskill Mountains
February 23, 2017 11:28 am
I just recently sent you a inquiry if you could help me identify this bug that we’ve seen more and more in the past 2 weeks. Seems like since the weather got a bit warmer, we’ve suddenly seen this bug.

Looks like a cockroach to me, but my husband says it’s not. Other people up here in Upstate New York, Catskill Mountains, have also seen them and don’t know what they are. Can you help me out with identifying this pest?

Never see them on the kitchen counters, and see about 10 a day in broad daylight. Has six legs and antennae. Dark brownish in color, and I believe they have wings, but I’ve never seen them fly. About 1/4 -1/2 inch in size.

Have spotted them throughout our first floor. We do have an unfinished basement that gets occasional water from rain. So please see if you can let me know what they are and what I can do to get rid of them. Thanks so much.

Dear Marie,
You have Eastern Boxelder Bugs, a species known to form large aggregations outdoors and to seek shelter indoors to hibernate once the weather cools. 

Once the weather begins to warm again, the hibernating Eastern Boxelder Bugs become active and attempt to gain egress to the outdoors, at which point they are noticed. 

Eastern Boxelder Bugs are harmless, and they will not damage your home, but they can become a nuisance when they are plentiful.

Thank you so much, Daniel.  You were a big help.  Not sure how to get rid of them though.  Any ideas?
Marie