What Do Boxelder Bugs Eat: A Friendly Guide to Their Diet

Boxelder bugs, scientifically known as Boisea trivittata, are insects that primarily feed on the seeds of boxelder trees (Acer negundo).

These true bugs have piercing-sucking mouthparts, allowing them to extract sap from various parts of plants.

In addition to boxelder trees, these insects also consume seeds produced by other maple species and plants like ash, spirea, strawberry, honeysuckle, plum, cherry, peach, grape, and apple.

Their feeding habits can vary with the change of seasons and the availability of their preferred food sources.

Environment and Habitat

Boxelder and Maple Habitats

Boxelder bugs primarily feed on the seeds of boxelder trees, but they can also be found feeding on other maple species.

These trees are commonly found throughout North America, including Canada. The bugs thrive in areas where boxelder and maple trees are abundant, such as your yard and property.

Besides maple trees, these bugs can also be associated with ash and maple trees,.

Boxelder bugs in these habitats increase in population during hot weather, making them more of a nuisance.

Indoor Infestations

While boxelder bugs are more commonly found outdoors, they can venture into your home in search of warmth and shelter.

During cold weather, boxelder bugs can find their way into homes through small cracks, crevices, or openings near doors and windows.

Keeping these pests outdoors is crucial to preventing indoor infestations. To keep your home boxelder bug-free, it is advisable to seal any cracks or holes in your home’s exterior, clear debris near your home, and keep plants well-trimmed.

Remember, a well-maintained yard and property will lessen the chances of boxelder bugs invading your home.

Maintaining a clean environment both indoors and outdoors is key to keeping boxelder bugs and other pests at bay. By taking these preventative measures, you can enjoy a boxelder bug-free environment in your home and yard.

What Do Boxelder Bugs Eat?

Boxelder Seeds Consumption

Boxelder bugs primarily feed on seeds produced by female boxelder trees. They use their piercing-sucking mouthparts to extract the sap from these seeds.

Boxelder bugs are not exclusive to boxelder trees, as they also feed on seeds from other maple species, such as the silver maple tree.

Feeding on seeds continues throughout the summer, allowing the nymphs to mature before cold weather arrives in the fall.

Fruit and Leaves Consumption

While boxelder bugs are mainly known for feeding on boxelder seeds, they may also attack other plants when in heavily infested areas.

These bugs have been observed feeding on leaves, tender twigs, and developing seeds of ash and maple trees.

Moreover, they may consume fruits like apples, plums, raspberries, and strawberries. Here are some common plants that boxelder bugs feed on besides boxelder trees:

• Apple trees
• Plum trees
• Raspberry plants
• Strawberry plants
• Silver maple tree
• Other maple species
• Ash trees

Boxelder bugs make use of their piercing-sucking mouthparts to suck sap from these fruits, leaves, and twigs.

It is important to note that while these bugs will consume a variety of plant materials, their primary food source remains boxelder seeds.

Life Cycle

Egg to Nymph Transformation

In the life cycle of boxelder bugs, females lay their red eggs in crevices of boxelder bark, on leaves, or other objects. The eggs hatch in about 11 to 14 days, releasing reddish-black nymphs.

Here are some characteristics of the eggs:

• Red in color
• Laid by female boxelder bugs
• Hatch in 11 to 14 days

As the eggs transform into nymphs, they go through several stages of development. The nymphs are wingless and possess wing pads. They are also sensitive to light and attracted to warm locations as they grow.

Nymph to Adult Progression

Throughout the nymphal stage, the nymphs gradually progress into adults. They’re usually darker towards their heads and have red abdomens. During their progression, they develop more prominent wings and antennae.

Here’s a comparison table of nymphs and adult boxelder bugs:

Feature	Nymph	Adult
Wings	Wingless with wing pads	Fully developed wings
Body color	Red abdomens, darker head	Mostly black
Legs, antennae	Short and black	Longer and black

Once the nymphs transform into adults, they become more active in searching for food and mates. They typically feed on the seeds and leaves of boxelder trees, as well as occasionally on ash and maple trees.

Behavior and Characteristics

Hibernation and Migration Patterns

Boxelder bugs, like several other insects, undergo a shift in behavior during the winter and fall seasons. In the fall, as the weather gets colder, they tend to search for sheltered areas to hibernate, such as cracks in trees or inside homes.

While they don’t necessarily migrate long distances, they do congregate in large swarms around warm locations.

During winter, you’ll likely find them hibernating in your attic, walls, or other hidden corners.

As the weather gets warmer, they become active again and return outdoors to resume feeding on seeds of boxelder and other maple species.

Survival Mechanisms

Boxelder bugs have developed a few mechanisms to help them survive and thrive.

One such feature is their ability to release a foul-smelling odor when threatened or crushed. This odor serves as a defense mechanism to deter predators.

Although boxelder bugs aren’t known to bite humans, they possess a piercing-sucking proboscis used for feeding on plant sap.

This allows them to obtain nutrients from a variety of plant species, including maple, ash, and even fruit plants like raspberry and strawberry.

While boxelder bugs might share some behavioral traits with other insects like beetles and cicadas, it is important to understand their unique characteristics for proper identification and management.

The following table compares certain aspects of boxelder bugs, beetles, and cicadas:

Insect	Feeding Mechanism	Type of Damage Caused	Swarm Behavior	Hibernation Strategy
Boxelder Bug	Piercing-sucking proboscis	Primarily feed on plants, not harmful to humans	Swarms in autumn to find hibernation sites	Hibernates in sheltered locations during winter (indoors/outdoors)
Beetle	Chewing mouthparts	Can cause significant damage to plants, some can be harmful to structures	Some species may exhibit swarming behavior	Various strategies depending on species
Cicada	Piercing-sucking mouthparts	Can damage plants but not considered pests	Emerges in large numbers every 13 or 17 years	Live underground as nymphs before emerging as adults

Potential Harms and Damages

Effects on Plants and Trees

Boxelder bugs can have a minimal impact on plants and trees. They primarily feed on the seeds and fruits of boxelder trees, as well as other maple species and sometimes ash trees, raspberry, and strawberry plants.

Although their feeding may reduce seed viability and cause damage to the fruits, it’s generally not considered serious or significantly harmful to the overall health of the host plants.

Effects on Homes and Buildings

In addition to their impact on plants, boxelder bugs can also become a nuisance for homes and buildings.

As the weather gets colder, they congregate in large numbers and seek shelter in cracks and crevices of walls, doors, and windows. This can lead to potential damages, including:

• Staining: When crushed or threatened, boxelder bugs release a bad odor and can also leave unsightly stains from their feces or defensive fluids on walls, curtains, or other surfaces.

• Punctures: Though it’s not their typical feeding behavior, these insects could potentially cause minor punctures in screens or building surfaces while trying to enter homes and buildings.

To minimize boxelder bug problems, the following preventative measures are recommended:

• Seal any cracks along the foundation, doors, or windows
• Caulk openings where utility cables enter the home
• Screen vents and apply weather stripping on doors

If you find boxelder bugs inside your home, avoid squishing them and causing stains. Instead, use a gentle sweep or vacuum to remove them. Also, ensure that your home is well-maintained to avoid any unwanted entry points for these pests.

Prevention and Control

Natural Predators

One natural way to control boxelder bugs is by introducing their natural predators, such as ants and spiders. These insects can help reduce the boxelder bug population around your property. For example:

• Ants like to feed on boxelder bug eggs and nymphs.
• Spiders can catch adult boxelder bugs in their webs.

Home Sealing and Cleaning

To prevent boxelder bugs from entering your home, make sure to seal cracks and crevices around your house. Here are some steps to take:

• Caulk any openings along the foundation, doors, or windows.
• Seal areas where utility cables enter your home.
• Screen vents and apply weather stripping on doors.

Regular cleaning is also crucial in controlling boxelder bugs. When you spot them, you can:

• Vacuum them up instead of squishing them, as they release a foul odor when crushed.
• Sweep them outside or use a hose with soapy water to wash them away.

Use of Pesticides

While pesticides can be effective, it’s important to consider the safety of your pets and the environment.

In some cases, using insecticides like malathion may be necessary to control large boxelder bug populations in trees. However, always consult a professional before using chemicals around your property.

Conclusion

In conclusion, boxelder bugs, or Boisea trivittata, have a diet primarily centered around the seeds of boxelder trees and other maple species.

Their feeding habits, facilitated by their piercing-sucking mouthparts, extend to a variety of plants including ash, spirea, and various fruit trees like apple, plum, and grape.

The seasonal availability of these food sources influences their feeding patterns.

Their habitat, predominantly around boxelder and maple trees across North America, plays a crucial role in their lifecycle and behavior.

While they are outdoor insects, boxelder bugs can invade homes seeking warmth during colder months, making preventive measures like sealing cracks and maintaining a clean environment essential.

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 – Eastern Boxelder Bug

Unknown bug in Saline Michigan during warm fall days
November 9, 2009
Hi Bugman, many of these bugs cover my black front door which faces south. They have managed to slip through the bottom of the door into the house where they tend to creep along the floor more than fly around. It has been very warm here in Michigan (above 50 F and sunnier than usual.
Curious, Lorraine
Saline, Michigan USA

Dear Lorraine,
Eastern Boxelder Bugs create tremendous aggregations that may contain thousands of individuals.  They are not considered a harmful insect, though their presence is often an annoyance when they try to enter homes in great numbers in the autumn to escape the winter chill.

Letter 2 – Eastern Boxelder Bug Nymph

Red eyed Bug
Hi bugman,
I have bookmarked your site, as living in Florida presents many different bugs, most of which I hadn’t been able to identify. I expect that will change with the help of your site. I have a bug around the outside of my home that I haven’t seen before. It’s kind of shaped like a stink bug, likely a beetle, but after searching your site, I couldn’t find anything. I have attached a picture, the “grid” is a standard household screen so that may provide a size estimate seven squares = approx 1cm. I have many of this little critters around from about 1/2 this ones size, to a little larger. I’d love to know what this odd bug with the bright red eyes actually is.
Thank you,
Randy Baker
Spring Hill, FL

Hi there Randy,
This is an Eastern Boxelder Bug, Leptocoris trivittatus, in its immature form. Adults have wings. In the fall, nymphs and adults form large aggregations. They feed on juice in the foilage of boxelder, maple and deciduous fruit trees.

Letter 3 – Eastern Boxelder Bug

Need help indentifying bugs in my basement.
Dear Bugman,
I hope I hear back from you because I have a seemingly significant population of one particular variety of bug in my basement that are getting to be a real pain. I live in Michigan and it is obviously winter here. I have never had an issue with this kind of insect prior this year, noticing them first in the late fall of ’05. The bug in question is predominately black on the back side with narrow orange stripes. It is primarily orange on the underside with black markings. It has six legs and one pair of wings. It flies, but is mostly seen attached to florescent lights in my basement office. Not counting it’s front antenna it is approximately 1/2 to 3/4 inches in length and it’s body (not counting leg span) is approximately 3/8 of an inch in width. While there seems to be steady stream of these bugs, I rarely see more than one or two at a time. If I can identify what this bug is it would go a long way to enable me keep the little beasts out of my basement. To help with your identification I have attached two digital photos. The object at left is a screw on pop bottle top as to lend some scale to the image. Your help would be greatly appreciated.
Thanks,
Mark Hatton

Hi Mark,
The Eastern Boxelder Bug, Boisea trivittatus, often seeks shelter indoors to hibernate. This insect also forms large aggregations with hundreds or even thousands of individuals.

Letter 4 – Eastern Boxelder Bug Aggregation

What’s This Bug
May 16, 2010
I live in Roanoke Rapids, NC which is right on I95 just before you reach the VA border. It has been in the 90s the last couple of days. When I returned home today from Weekend College my wife showed me two colonies of these bugs. What kind of bug are they? and do I have to worry about them?
Howard L. Bethany
Roanoke Rapids, NC

Hi Howard,
This is an aggregation of Eastern Boxelder Bugs, Boisea trivittata.  Both the winged adults and wingless nymphs feed on the seeds of boxelder and maples, but they do not harm the trees.  Most of our reports come in the autumn when large aggregations are formed and the adults sometimes enter homes to hibernate.  When Boxelder Bugs are extremely plentiful, they can be a nuisance, but they are not cause for alarm.  You can read more about Boxelder Bugs on Bugguide.

Letter 5 – Eastern Boxelder Bug

Subject: What kind of bug?
Location: Illinois
March 10, 2013 3:22 am
These bugs are overwhelming us. What can we do to get rid of them? Seem to be attracted to wood.
Signature: Sandy Berg

Dear Sandy,
Eastern Boxelder Bugs or Democrat Bugs, Boisea trivittata, often enter homes in great numbers to hibernate.  The best way to safeguard against this is to weatherproof your home and eliminate any small cracks and gaps where they can gain entry.

Letter 6 – Eastern Boxelder Bug

Subject: What is this bug?
Location: Ottawa Canada
March 27, 2013 6:11 pm
I started to see these bugs last year. They start out as tiny pin head size bugs that are totally red. There are thousands in a nest which looks like a moving bunch of red dots. As they grow they start to become black untill they are mostly black with a little red. They also can fly. They were everywhere in the fall. Thousands of them all over my house and I saw a lot of nests on my property. They seem to be harmless as they will walk on you and not bite. The only bother is the sheer number and now that spring has come, they seem to be coming from nowhere. I am just curious as I have never seen this bug in my life. They seem to be about 1/2” full grown, six legs and two antenna. Thanks.
Signature: Harry Van Hofwegen

Our Automated Response
Thank you for submitting your identification request.
Please understand that we have a very small staff that does this as a labor of love. We cannot answer all submissions (not by a long shot). But we’ll do the best we can.

Hello:
Thanks for your email.  Crazy thing, but I have looked for a long time and I just stumbled on an image of this bug so I just figured it out.  It is a Boxelder bug.  I have never seen them around my home ever until last year and now I have thousands of them.  I appreciate you guys and the work you do for people.  I hope they will leave soon because they are annoying.
Cheers,
Harry

Hi Harry,
We are happy to hear you quickly identified your Eastern Boxelder Bug once you discovered our site.  We have numerous postings of the aggregations the Eastern Boxelder Bugs form, especially in late summer and autumn.  They feed on the seeds of boxelder trees and other maples, so we assume you have a large maple tree or trees near your home.  Boxelder Bugs also enter homes in the fall to hibernate.  Boxelder Bugs often have isolated populations that are very numerous, but several hundred feet away, they are noticeable absent.  Their populations might also fluctuate greatly from year to year.  We suspect if the conditions are right for them in your yard, they are most likely there to stay.  We will be away from the office for a few days for the holidays, so we are postdating your submission to go live later in the week.

Letter 7 – Eastern Boxelder Bug

Subject: Beetle
Location: West Chester PA
November 15, 2015 10:19 am
Found this sun-loving bug on the wall and between the window and screen. In groups.
Signature: Kathleen

Dear Kathleen,
The Eastern Boxelder Bug is not considered a pest species, but when they are present in large aggregations, many folks consider them to be a nuisance, especially when they enter homes to hibernate with the onset of colder weather.

Letter 8 – Eastern Boxelder Bug nymphs eat dead mouse

Subject: Are These Jadera Bugs eating this mouse?
Location: Brevard, North Carolina
October 8, 2016 8:42 pm
Are these Jadera bugs eating this dead mouse?
Signature: Eric

Dear Eric,
Though they resemble Red Shouldered Bug nymphs, Jadera haematoloma, as you can see in this BugGuide image, but these are actually Eastern Boxelder Bug nymphs, Boisea trivittata, based on this BugGuide image.  According to North American Insects and Spiders:  “All instars eat maple seeds; later instars are carnivorous scavengers of insect carcasses as well. All developmental stages congregate on sunny surfaces, especially wooden surfaces proximate to their food source.”  Your image indicates they are opportunistic, and they will scavenge more than just insect carcasses.

Letter 9 – Eastern Boxelder Bug

Subject: bug unknown
Location: Northern Virginia
November 10, 2016 6:05 am
We found this bug around our house. Especially when then weather is warm. Not a firefly. Not sure what it is. Thanks for identify!
Signature: Not sure

This is an Eastern Boxelder Bug, commonly called a Democrat Bug because of the large aggregations they sometimes form.

Letter 10 – Eastern Boxelder Bug Nymphs

Subject:  Beetle ? Pine Borer ?
Geographic location of the bug:  North New Jersey
Date: 09/01/2017
Time: 05:25 PM EDT
I just cut down 2 large white pine trees a couple months ago. Now I am finding what I swear are 1 million of these bugs on my other trees and in the fallen pine needles.
I dont know if they are harmful to humans, my pets or the other trees, whether they should be left alone, removed somehow.
Any help would be appreciated.
thanks,
How you want your letter signed:  Bob

Dear Bob,
These are Eastern Boxelder Bug nymphs, and although they are harmless, when they are present in large numbers, they can be quite a nuisance.  They are sometimes called Democrat Bugs.

Letter 11 – Eastern Boxelder Bug

Subject:  bugs on house siding
Geographic location of the bug:  agawam, ma
Date: 11/05/2017
Time: 02:43 PM EDT
tons of these bugs on outside of house. never had them before
How you want your letter signed:  Don Williams

Dear Don,
This is an Eastern Boxelder Bug, a species that often aggregates in large numbers.  Houses with light colored, south facing walls that are in the sun are favorite locations for aggregating.  Eastern Boxelder Bugs are also known to enter homes to hibernate once weather begins to cool.  The aggregations have led to common names like Populist Bug and Democrat Bug. 

Letter 12 – Eastern Boxelder Bug

Subject:  Is this a kissing bug
Geographic location of the bug:  Northfield, Minnesota
Date: 10/01/2021
Time: 04:00 AM EDT
Your letter to the bugman:  This particular one has been infesting and appearing all across my campus – I wanted to confirm any possibility that it is a kissing bug or some invasive species.
How you want your letter signed:  To: Alexander

Dear Alexander,
This is not a Kissing Bug or Blood-Sucking Conenose Bug, the insect that spreads Chagas Disease.  This is an Eastern Boxelder Bug which you can verify by comparing your image to this BugGuide image.  Kissing Bugs and Boxelder Bugs share some physical features which is why they are classified together in the insect order Hymenoptera.  Eastern Boxelder Bugs do not suck blood and they are not dangerous, but they are sometimes considered a nuisance when they form large aggregations on homes and in yards.