How To Get Rid Of Elm Seed Bug? Helpful Tips.

Did you see a nasty-looking black bug with orange streaks on its back? It’s probably the elm seed bug. Here’s how to get rid of elm seed bugs in your home.

Stink bugs, as the name suggests, can stink up your home, especially if they are present in large numbers.

The Elm Seed Bug, although not technically a stink bug, has many of the same properties.

Although not native to the US, these bugs have become very common and are known to invade homes in swarms.

In this blog, we shed light on these invasive pests and how you can get rid of them.

How To Identify Them?

Effective pest control starts with identifying the bugs you are dealing with. The adult elm seed bug ranges from a quarter to a half inch in size.

It has a black or reddish-brown body with unique triangular markings on the back. It can emit a foul odor that will remind you of bitter almonds.

It shares several similarities with the boxelder bug, which is why people often get confused between the two insects.

However, boxelder bugs are darker and have orange markings on their backs, unlike elm seed bugs.

Elm seed bugs come from a different family of bugs called seed bugs, which feed on the seeds of various plants.

How To Prevent Them From Entering?

Although these invasive pests aren’t harmful to humans, pets, or plants, they can stink up your home. This stink is actually their defense mechanism, and it keeps away predators.

Large elm seed bug populations can be a problem due to their mere presence. Below are a few tips on keeping them out:

Sealing off cracks

This is, of course, the most obvious way to make sure stink bugs can’t enter your home. You need to block all the entry points to deny them a way into your home.

Installing fine wire mesh screens in the windows and the doorways is a great way to stop pests from entering without blocking natural light and airflow.

However, there are other entry points that the invasive bug can exploit, such as cracks and holes in your walls.

Look for cracks and voids on the external walls of your home, especially if your home suddenly has many bugs and you aren’t sure how they’re getting in.

Use a sealant like caulk to seal and block all these entry points. As long as the bugs have a way to enter your home, an infestation can always break out.

Keep your property clean.

A dirty yard full of trash not only looks untidy but also attracts a host of pests to your property. Debris doesn’t refer to garbage alone – dead plant matter from your garden counts as well.

The presence of such plant matter can attract stink bugs, and they will eventually find their way into your home. Clean your yard properly to prevent such infestations, especially if there are elm trees on or near your property.

Elm Seed Bug

Other tips

It’s quite common for people to carry overwintering elm seed bugs home on firewood. Inspect the wood carefully before you take it inside.

Carrying out a perimeter treatment with residual pyrethroid insecticides is a good way to keep elm seed bugs out.

How To Get Rid of Them?

Squishing elm street bugs isn’t advisable as it would trigger them to release their odor and stink up your house.

Even if you try to scare it away from your home, the est will release its foul odor. So getting rid of these bugs needs a bit of thought.

Some ideas that might work include vacuuming or using mild pesticides such as deltamethrin dust


An effective way to remove elm seed bugs without startling them or allowing them to release their unpleasant odor is to suck them up with a vacuum.

Unlike picking up bugs by hand, vacuuming will not let the pests get time to release their stink spray. Even when they do, it would be inside the vacuum cleaner.

Using a vacuum is a particularly easy solution when dealing with large clusters of elm seed bugs. Once done, you can throw them all out in one scoop and change the bag.

You can also put some soapy water in the dust container to reduce the stink and kill the bugs.

Using pesticides

You can also eliminate the elm seed bugs by using pesticides, but you need to be careful as most pesticides are too toxic for indoor use.

Cyonara-based insecticides are good against these pests, but they are suitable only for outdoor use. You may treat your lawn, gutters, and exterior perimeter with this type of pesticide.

For non-traffic areas like attics and crawl spaces, you can use deltamethrin dust against these invasive pests.

If you have to use pesticides in living spaces, choose a relatively less toxic pesticide made from natural ingredients and use it in small amounts.

How To Get Rid Of Elm Seed Bug? Helpful Tips

Frequently Asked Questions

What pesticide kills elm seed bugs?

Pyrethroid-based pesticides work best against elm seed bugs. These include synthetic pyrethroids like permethrin, cyfluthrin, and bifenthrin.

However, be careful when choosing a pesticide for indoor use, as it can pose a hazard to your family or pets. If possible, use other methods, such as vacuuming them up or using soapy water.

How long do elm seed bugs last?

Elm seed bugs can live up to five years. They are different from most other bugs that have smaller life cycles.

This makes elm seed bug infestations particularly frustrating as they can reproduce for several seasons and cause their numbers to add up significantly.

How do I keep elm beetles out of my house?

Blocking all potential entry points is the best way to keep elm beetles out of your home. You can use caulk to seal off wall cracks and install wire mesh screens in your windows and doorways.

As mentioned earlier, insecticide treatment of the perimeter helps. You also need to check the wood that you are bringing in for your fireplace.

How do you trap elm beetles?

You can trap elm beetles using sticky traps. Place these traps around entry points, such as window sills.

Many sticky traps also use pheromones to attract bugs. This is also an effective way to trap beetles infesting hard-to-reach parts of your home in large numbers.

Wrap Up

You should be especially vigilant about these bugs during late summer and fall. The elm seed bug activity decreases during the colder months, during which time they overwinter.

They lay eggs in elm trees and rarely reproduce indoors. However, there are many reports of these bugs infesting homes. Now that you have read this article, you can deal with them effectively. Thank you for reading.

Reader Emails

Over the years, many of our readers have checked in with us about this new type of bug stinking up their place.

We wanted to share with you some of these emails to help you understand just how bad it can get and how much people want them out of their houses!

Letter 1 – Elm Seed Bug Infestation in Idaho


Subject: everywhere
Location: Lewiston Idaho hot dry low elevation pacific northwest
July 8, 2014 6:37 pm
These little tiny beetle shaped insects fly all over they just came out of every crevasse of the house they are dark brown and there are tons they are like termites in basically but I’m not sure I don’t think it is a type of termite please help
Signature: they’re everywhere

Elm Seed Bug
Elm Seed Bug

Dear t.e.,
Last year we posted a letter, also from Idaho, regarding an infestation of Elm Seed Bugs,
Arocatus melanocephalus, and since that time, we have received many comments.  ABC News reported on this dilemma a year earlier in July 2012.  Boise local KTVB News also reported on this infestation last July.  This is an invasive species introduced from Europe, and until a natural predator is discovered, we suspect they will continue to spread in North America.

Letter 2 – Possibly Elm Seed Bug infestation in Oregon


Subject: What are these guys?
Location: Bend Oregon USA
July 2, 2017 4:15 pm
A big hatch yesterday in 85 degree weather. Came out of side of wood storage shed. Bend, Oregon
White moth pic isn’t related, just for fun. Always love to see their intricate wing art
LOVE your FB page! Thanks!
Signature: Always Curious

Possibly Elm Seed Bug Infestation

Dear Always Curious,
These are definitely True Bugs and they appear to be immature nymphs, which sometimes makes exact identification difficult.  If you are able to send an image of a winged adult, that might help.  Our first impression is that this might be an infestation of Elm Seed Bugs, an invasive, introduced species that has spread in Washington, Idaho and Utah as well as Oregon according to BugGuideHermiston Herald does include an image of a nymph that looks very similar to what you have submitted.  We would not rule out that it might be an infestation of another invasive species, the Mediterranean Seed Bug.

Possibly Elm Seed Bug Infestation.
Oh m’gosh Thanks so much for the reply! I bet they are elm seed bugs as there are many elms around and many are diseased.
My gratitude!

Letter 3 – Invasive Elm Seed Bugs in British Columbia


Subject:  Elm Seed bug?
Geographic location of the bug:  Osooyos, BC Canada
Date: 01/22/2018
Time: 05:58 PM EDT
Your letter to the bugman:  Hi There
Just hoping to get conformation on this beetle.
Thank you
How you want your letter signed:  Hannah Rowe

Elm Seed Bugs

Dear Hannah,
We agree that these are invasive Elm Seed Bugs,
Arocatus melanocephalus.  According to BugGuide:  “Native to, and widespread in S. & C. Europe, established and spreading in w. NA (BC-OR-ID-UT)” and “Invades homes during summer, may stay through the winter.” 


  • Bugman

    Bugman aka Daniel Marlos has been identifying bugs since 1999. is his passion project and it has helped millions of readers identify the bug that has been bugging them for over two decades. You can reach out to him through our Contact Page.

  • Piyushi Dhir

    Piyushi is a nature lover, blogger and traveler at heart. She lives in beautiful Canada with her family. Piyushi is an animal lover and loves to write about all creatures.

7 thoughts on “How To Get Rid Of Elm Seed Bug? Helpful Tips.”

  1. I have caught eight or ten of the insects (elm seed bug) in my house over the last month. How do I get rid of them?
    Boise, Idaho , October, 2014

  2. These are now showing up in Ephrata Wa also. While they aren’t a horde they seem to be here in fairly high numbers. I’ve lived here for 14 years and had never seen these before this year. There are lots of Elm trees here and as anyone that lives near a large elm tree they are quite prodigious with their seed production. At time in late May into mid June the elms shedding their seeds appears almost like snow fall. Heavy snow fall.

  3. I’m completely grossed out. I haven’t slept in 2 nights. These Elm Seed Bugs have invaded and are driving me batty. So glad to finally put a name to these. We have tons of Chinese elm trees in this town. Now how do I get rid of them?


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