Western Conifer Seed Bug in House: Quick Solutions for Removal

As fall approaches, you might be surprised to find some uninvited guests in your home — the western conifer seed bug (WCSB). These herbivorous insects are native to western North America, but have spread eastward since the 1950s. They feed on conifers, including various pines, spruces, hemlocks, and Douglas fir. While their feeding habits don’t impact the health of trees, these bugs can become a nuisance when they invade homes seeking warmth and shelter during the colder months.

You may find these reddish-brown bugs, approximately 3/4 inch long, with a white zig-zag pattern on their wings, hanging around your windows or crawling on your walls. Although they may appear threatening, WCSBs are harmless to people, pets, and your home’s structure. But, nobody wants these uninvited guests overstaying their welcome. So, how can you deal with a western conifer seed bug infestation in your house? In this article, we will discuss some simple yet effective methods to keep these bugs at bay and prevent future infestations.

Understanding Western Conifer Seed Bugs

Identifying Characteristics

The Western conifer seed bug (Leptoglossus occidentalis) belongs to the family Coreidae. These insects have some distinguishing features that set them apart from other insects:

  • Body length: They are about 3/4 inch (19mm) long.
  • Wings: Their wings have a mottled dark brown color, with a faint white zigzag line across the center.
  • Hind legs: They have flattened, leaf-like hind legs.
  • Antennae: Long and thin.

They are often confused with the brown marmorated stink bug, but the Western conifer seed bug is longer and narrower. You can easily identify them by their distinct piney odor when handled.

Life Cycle

The life cycle of Western conifer seed bugs involves several stages:

  1. Eggs: Adult females lay chains of tiny eggs (less than 1/10″) on conifer needles.
  2. Nymphs: After hatching, the nymphs go through five developmental stages. They start out as orange and gradually turn darker as they mature.

When fully grown, the insects are strong fliers, capable of covering significant distances.

Habitat and Range

Western conifer seed bugs are native to western North America, where they feed on conifers such as pines, spruces, hemlocks, and Douglas firs. Their feeding does not impact the health of the trees, but they can be annoying when they invade homes during the fall.

The insects’ range has expanded dramatically since the 1950s. They are now found throughout the United States, including in the eastern part of the country. The bugs have also been reported in countries like Turkey, Chile, and Japan, demonstrating their adaptability to different environments.

To keep them out of your home, it’s essential to seal any exterior cracks and equip foundation and attic vents with tight-fitting screens during warmer months. If you find Western conifer seed bugs indoors, consider vacuuming them up as a safe and effective removal method.

Why They Invade Homes

Seasonal Changes

Western conifer seed bugs seek refuge in homes due to seasonal changes. As fall approaches, the temperature drops, and these bugs start looking for warm places to overwinter. Your home can provide the perfect shelter for them to survive the cold months.

During spring, overwintering insects like western conifer seed bugs emerge from their hiding places. You might notice them in your house as they attempt to leave and return to their natural environment.

Searching for Food

These bugs feed on conifers such as pines, spruces, hemlocks, and Douglas firs during the warmer months. However, when fall arrives, their food source may become scarce. Consequently, they search for new food sources and often end up in your home.

When they invade your house, remember that they are not harmful to you or your property. As overwintering insects, they don’t build nests or cause structural damage; they only seek shelter. Therefore, it’s essential to maintain your home’s cleanliness and take preventive measures to keep them at bay.

To avoid future invasions, consider these steps:

  • Equip foundation and attic vents with tight-fitting screens
  • Seal any exterior cracks
  • Regularly vacuum your home, especially in areas where you found the bugs

By taking these measures, you can make your home less inviting for western conifer seed bugs and other overwintering insects during the fall and spring seasons.

Impact of Infestation

Homeowners may experience some issues when western conifer seed bugs find their way indoors. These insects tend to be attracted to the warm interiors of homes, and as temperatures drop, they may begin to enter your home in search of a place to overwinter.

Although western conifer seed bugs do not cause any significant damage to homes or plants, they can be quite a nuisance. They are often confused with stink bugs, which is another type of insect that produces a strong odor when disturbed or crushed. While the odor emitted by western conifer seed bugs is not as strong as that produced by stink bugs, it can still be unpleasant.

Additionally, these home invaders do not reproduce indoors, and they are not known to bite or transmit diseases. The infestation is mainly about the annoyance caused to the homeowner.

Here are some general tips to help manage western conifer seed bug infestations in your home:

  • Seal any cracks or gaps in your home’s exterior to prevent bugs from entering.
  • Install or repair window screens to keep bugs out.
  • Vacuum up any bugs you find indoors and dispose of them outside.
  • Avoid using insecticides, as these chemicals can be harmful to beneficial insects and may not be effective for controlling western conifer seed bug infestations.

Remember to stay calm and patient when dealing with these pesky intruders. By taking these simple preventive measures, you can minimize the impact of western conifer seed bug infestations in your home.

Prevention Strategies

House Insulation and Repair

To prevent western conifer seed bugs from entering your home, take steps to improve your house insulation and repair. One method is to inspect your windows, doors, and window frames for any cracks, and then seal these openings with caulk. Keep an eye on the siding, fascia, eaves, and soffits as well, as these areas can also harbor crevices where bugs can sneak in.

Examine your home’s foundation, looking for any entry points that might need attention. Filling these openings will not only help with bug prevention but also improve your home’s overall insulation.

Effective Use of Screens and Traps

Installing screens on your windows and doors can significantly reduce the chances of western conifer seed bugs finding their way into your home. Ensure gaps are small enough to prevent them from squeezing through.

Traps are also an option for controlling and reducing the population of these bugs. Sticky traps can be placed near doors, windows, or areas where you have spotted them before. Remember to replace traps regularly for maximum effectiveness.

In summary:

  • Inspect and seal cracks, openings, and crevices around windows, doors, siding, fascia, eaves, and soffits.
  • Caulk and repair any gaps or entry points in your home’s foundation.
  • Install screens on windows, doors, and other openings.
  • Use sticky traps near doors, windows, and other points of entry to capture bugs.

By following these prevention strategies, you can help keep your home free from western conifer seed bugs and maintain a comfortable living environment.

Removal Techniques

Non-Chemical Methods

Vacuuming

One simple method to remove western conifer seed bugs from your house is by using a vacuum cleaner. This can help you quickly and efficiently capture these pests without harming them or your environment. Simply aim the vacuum hose at the bugs and suck them up.

Soapy Water

Another non-chemical option is to use a mixture of soapy water to kill and remove the bugs. Fill a spray bottle with water and a few drops of liquid dish soap, then spray it directly on the bugs. The soapy mixture will suffocate the bugs, making them easier to remove.

Chemical Methods

Pesticides

If the infestation is severe, you may consider using pesticides. Many common household insecticides can be effective in controlling western conifer seed bugs. However, take caution when using chemical pesticides and follow the label instructions.

Permethrin

Permethrin is an insecticide that can be used against western conifer seed bugs. This chemical can be applied as a spray or dust to the areas where the bugs are found, helping to eliminate the infestation.

Bug Zappers

Although not the most effective method, bug zappers can sometimes help control western conifer seed bug populations. Position the zapper in areas where the bugs are most commonly seen. Keep in mind, however, that bug zappers will also attract and kill other insects, including beneficial ones.

To determine which method is best for you, here’s a comparison table:

Method Pros Cons
Vacuuming Non-toxic, safe for the environment May not eliminate entire infestation
Soapy Water Non-toxic, inexpensive Time-consuming, may require multiple sprays
Pesticides Effective, fast-acting Toxic to humans and the environment
Permethrin Effective, long-lasting Toxic to humans, pets, and the environment
Bug Zappers Easy to use, covers large area Kills other insects, not the most effective

By understanding these removal techniques, you’ll be able to make an informed decision on how to deal with the western conifer seed bugs in your house.

Dealing with Dead Bugs

If you find dead western conifer seed bugs in your house, don’t worry, they won’t sting you. Follow these simple steps to clean them up and prevent odors:

  1. Vacuum them up: Use a vacuum cleaner to easily dispose of the dead bugs. Make sure to empty the vacuum bag or container into an outdoor trash can to avoid unpleasant odors.

  2. Wear gloves for manual removal: If you prefer picking up the bugs by hand, use a pair of gloves to protect against any potential allergens or irritants. Dispose of the bugs in an outdoor trash can.

Here are some key points to remember:

  • Western conifer seed bugs don’t sting or bite
  • They may release a foul odor when disturbed or crushed
  • Regular cleaning can help prevent accumulation of dead bugs

By following these steps, you’ll be able to effectively deal with dead western conifer seed bugs in your home. Remember to always dispose of them outside, and keep your home clean to avoid any unwanted smells and future invasions.

Interactions with the Tree Ecosystem

Types of Trees They Infest

The Western Conifer Seed Bug is known to infest various types of conifer trees. Some examples include:

  • Pines
  • Douglas firs
  • Hemlocks
  • White spruces

These insects have a sap-sucking mouthpart allowing them to feed on the seeds within pine cones, potentially impacting the reproductive success of the trees.

Their Role in the Ecosystem

Despite being considered a tree pest, the Western Conifer Seed Bug’s impact on the overall health of conifer trees is minimal. While their feeding can cause some damage to individual seeds, they do not pose a significant threat to the trees themselves. In fact, the presence of these bugs can contribute to the ecosystem by providing a food source for predators such as birds.

Remember, it is essential to maintain a balance between managing tree pests and preserving the ecosystem. With that in mind, although the Western Conifer Seed Bug may cause minor disruptions, its overall role as a participant in the ecosystem is vital.

Western Conifer Seed Bugs and Other Insects

Similar Insects

Western conifer seed bugs (WCSB) belong to the leaf-footed bug family Coreidae, and they can sometimes be mistaken for other household pests. Here are some similar insects to help you identify WCSB:

  • Assassin bugs: These insects have a narrow body and a distinct curved beak. Unlike WCSB, they are predators that feed on other insects.
  • Kissing bugs: Triatominae, also known as kissing bugs, feed on blood and can transmit Chagas disease. They are brown, wingless, and have a rounded abdomen.
  • Wheel bugs: A member of the assassin bug family, wheel bugs have a prominent spiked crest on their back. They also prey on other insects.
  • Brown marmorated stink bugs: These pests are shield-shaped, have a marbled brown color, and release an unpleasant smell when threatened. They are different from WCSB due to their shape and smell.

Natural Predators

A variety of predators can help control the WCSB population. Recognizing them can be useful in controlling pest infestations. Some natural predators include:

  • Spiders: Various species of spiders prey on WCSB and other insect pests.
  • Praying mantises: These large, distinctive insects are well-known for their predatory behavior, including feeding on WCSB and other insects.
  • Birds: Some birds, such as blue jays and woodpeckers, feed on WCSB, helping to regulate their numbers.

By understanding the differences between WCSB and other insects, you can identify and manage pests more effectively. A combination of natural predators and other control methods can help keep your home free from unwanted insect infestations. Remember to stay informed and maintain a proactive approach to pest control.

Health and Safety Concerns

You might be worried about the presence of western conifer seed bugs in your home. It’s natural to have concerns, especially regarding potential bites, disease, and whether they are harmful. Here are some key points to help ease your mind:

  • Bite: Thankfully, western conifer seed bugs do not bite humans. Although they have piercing mouthparts that help them feed on conifer seeds, you won’t have to worry about them biting you or your family members.

  • Harmless: These bugs are generally harmless to humans and pets. They are considered more of a nuisance than a threat, primarily because they tend to seek shelter in buildings during the colder months. Nevertheless, they won’t damage your home or possessions.

  • Disease: There are no known diseases associated with western conifer seed bugs. They don’t transmit any illnesses to humans or pets, so you can rest easy knowing they won’t cause any health issues.

  • Bodies: When you find dead western conifer seed bugs in your home, dispose of them promptly. This can help minimize any potential allergens caused by their bodies. Remember, they are not harmful, but it’s always good practice to keep a clean environment.

To sum it up, western conifer seed bugs are mostly harmless and pose minimal health and safety concerns. However, it’s essential to maintain a clean living space and dispose of any dead bugs to avoid further issues.

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 – Western Conifer Seed Bug: Seeks shelter indoors when weather tuns cold

 

Help me ID bug in Chicagoland area
Sun, Jan 18, 2009 at 1:17 PM
One of these appears about every 7-10 days in a second floor bathroom. It’s now the dead of winter and I saw a few more of them in late fall. Can you help identify? It is about 1 inch long. Thanks
TW
Northeern Kane County IL

Western Conifer Seed Bug
Western Conifer Seed Bug

Dear TW,
The Western Conifer Seed Bug, Leptoglossus occidentalis, is a harmless creature that seeks shelter indoors when the weather turns colder.  Interestingly, in the past 30 years, this species has undergone tremendous range expansion from its native Pacific Northwest to include much of Canada and the northern portions of teh Eastern and Midwestern U.S.

Letter 2 – Western Conifer Seed Bug entering home

 

Subject:  Beetle ?
Geographic location of the bug:  Catskill New York
Date: 10/15/2017
Time: 10:15 AM EDT
Hundreds of these bugs on and around my house. Also finding their way into my house.
Can you tell me what they are ? Are they pests or are they good for my garden ?
Thank you !
How you want your letter signed:  Deb

Western Conifer Seed Bug

Dear Deb,
Though it is a North American species, one can make the argument that the Western Conifer Seed Bug is an invasive species when it is found outside its original range of the Pacific Northwest.  Beginning in the 1960s, there was a noticeable range expansion across much of North America and eventually into Europe, and this range expansion is probably due to human assistance.  Western Conifer Seed Bugs will enter homes when the weather begins to cool, and they probably stowed away in luggage and other items that people took with them when they traveled or relocated.  Though Western Conifer Seed Bugs feed on the seeds of conifers, there is no evidence they harm the trees themselves.

Thanks Daniel,     Cannot believe how many are crawling on my house, trying to get in. Some actually do and eventually die.  Is there any correlation between the enormous number of pine cones this fall and the appearance of theses Conifer Seed Bugs ?
Thanks again !
Deb
Hello again Deb,
Your observation that there is a greater food supply in the form of pine cones is a likely reason there are greater numbers of Western Conifer Seed Bugs this year.

Letter 3 – Western Conifer Seed Bug enters home

 

Vain bug caught checking himself out in our bathroom mirror!
Location: Littleton, CO
November 18, 2011 6:54 pm
My son discovered this guy in our bathroom on the mirror. He freaked out, thinking it was an ugly bug that would attack him or something. I grabbed the camera and took pictures before placing him back outside because I thought it was kind of cool looking. Is it some kind of grasshopper? Doesn’t look like the type I am used to seeing around here but I have no clue what else it might be. Thanks for your help!
Signature: Lynette

Western Conifer Seed Bug

Hi Lynette,
As soon as the weather begins to cool appreciably, Western Conifer Seed Bugs like the one in your photo and some other Hemipterans, like the Brown Marmorated Stink Bug and Boxelder Bug enter homes to hibernate.  They do not cause any damage to the home, its furnishings or its inhabitants.  The Western Conifer Seed Bug,
Leptoglossus occidentalis, is native to the Pacific Northwest, but beginning in the 1960s, it greatly expanded its range, probably because of accidental introduction to new regions by humans when the Western Conifer Seed Bug was transported with luggage, packages and other methods of moving goods.

Letter 4 – Western Conifer Seed Bug found in home

 

Subject: Unidentified bug
Location: Illinois – northwest Suburb of Chicago
March 25, 2016 6:59 pm
I have found a couple of these bugs in my bathroom (southwest exposure) but I have never seen them anywhere else in my home. What kind of bug is this?
Signature: Whatever way you like

Western Conifer Seed Bug
Western Conifer Seed Bug

Western Conifer Seed Bugs often enter homes to hibernate when the weather cools.    When the weather warms, they reveal themselves as they attempt to seek egress. 

Letter 5 – Western Conifer Seed Bug found in Toilet!!!

 

Western conifer seed bug
Location: Minticello, MN
February 16, 2011 10:51 am
Hello!
Great website! I was able to ID my bug in just a few minutes by searching for my state on your website. I found it in the one of the toilets where I work, and couldn’t tell if it was alive or not. I’m guessing a member of the cleaning crew knew of the critter’s reputation to stink when squished, and decided to flush it. Just thought I’d pass along the picture since it shows some good detail of the little guy (or girl?). Thanks again for the resource!
Signature: Anne

Western Conifer Seed Bug

Dear Anne,
We are very happy to hear that you were able to easily identify this Western Conifer Seed Bug using our website.  We were also terribly amused by your email.  We think it is awesome that you took the time to photograph this bathroom melodrama and then to research the identity of the poor creature that is most certainly out of its element.  Your email did not indicate if there was a water rescue or if this hapless Western Conifer Seed Bug got flushed.  We prefer to thing that there was a happy ending.

Letter 6 – Western Conifer Seed Bug enters home

 

Subject: Colorful Bug
Location: richmond heights ohio
January 24, 2016 10:17 pm
On the bed, January, in Ohio,
Should I be looking for exterminator?
Signature: letter?

Western Conifer Seed Bug
Western Conifer Seed Bug

In our opinion, in this case an exterminator is a waste of money.  Western Conifer Seed Bugs like the one in your image are native to the Pacific Northwest, but in the 1960s, perhaps due to a major increase in travel, the species greatly expanded its range, now being found in most of North America and most recently being reported from Europe as well.  Western Conifer Seed Bugs frequently enter homes to hibernate when the weather cools.  They will not damage your home or its furnishings and they pose no threat to you or your pets.  They can be an annoyance if they enter homes in great numbers, but they are not breeding indoors.

Letter 7 – Western Conifer Seed Bug

 

I found this bug in my bedroom and I have found others of the same type. Until today I didn’t know they could fly. I know the pictures aren’t that good. The bug is less than inch long and doesn’t move too fast. I’ve only found then in my bedroom. I am concerned they could be some kind of parasitic beetle. Help

You do not have beetles, but Western Conifer Seed Bugs, Leptoglossus occidentalis.

Letter 8 – Western Conifer Seed Bug

 

Beetle infested!!
Dear Whats that Bug,
Hi there, I was hoping you could tell me what this beetle is and why this year all of a sudden they appeared. They started about a month ago invading the house coming thru the cracks around the windows (we have a very old house not bug proof we live with spiders and bugs) and they were outside waiting for their opportunity to come in ! The really weird part is when you pick them up or try and get them outside they put off a very potent smell almost chemical like. They actually come in two different colors there’s this one that is kind of reddish and then there is a grey and blackish with same markings as the red ones. I have lived here my whole life and have never seen them like this. We live in Northern CA in the Redwood country its about 9 miles inland from the coast. Thank you so much for your help if you can identify these.
Melissa

Hi Melissa,
You don’t have beetles, but Western Conifer Seed Bugs, Leptoglossus occidentalis. They often seek shelter indoors to hibernate.

Letter 9 – Western Conifer Seed Bug

 

Hi Bugman,
In the Slocan Valley in British Columbia there are stink bugs everywhere. My son took these photos. I would like to identify this particular bug so that I can learn what attracts them and how to get rid of them. There are various theories; stink bugs are attracted to light colors, they come into the house with the firewood, they come inside to get out of the cold, they were introduced as a predator for another species, they are naturaly occuring in this area, ladybugs will control them, etc. We are building a small resort and would like to make our buildings stink bug proof. Any info would be greatly appreciated.
Thanks,
Isy

Dear Isy,
You have a Western Conifer Seed Bug. The Western Conifer Seed Bug, Leptoglossus occidentalis was first described in California in 1910 and prior to 1969, it was only known in the Western U.S. Then it started to move East. By the 1970’s it was established in Wisconsin and Illinois, and by the mid 1980’s was found in Minnesota, Michigan and Ontario. In 1990 this species was collected in New York State and in 1992 it was found in Pennsylvania. It is also present in Mexico. The Western Conifer Seed Bug is a True Bug from the Family Coreidae, the Big Legged Bugs or Leaf Footed Bugs. It is a pest on conifer trees. We have no theory about how to keep them out of your resort. That is a question for your contractor.

Letter 10 – Western Conifer Seed Bug appreciates fine art rugs

 

Please help ID this insect
October 20, 2009
Monday morning in our Fine Art Gallery I opened up at 8:30 Am and found this brown and tan friend walking across the oriental rug in gallery 3. I moved him outside and he flew away. Tuesday morning comes around and there it is again walking across the same rug.
JB
Connecticut

Western Conifer Seed Bug
Western Conifer Seed Bug

Hi JB,
At this time of year we receive scores of reports of Western Conifer Seed Bugs entering homes to escape the cold.  We are amused that your individual is an art appreciator.  Western Conifer Seed Bugs are harmless.

Letter 11 – Western Conifer Seed Bug

 

Is this a cricket?
November 26, 2009
What type of insect is this. It is about 1 inch long and very slow moving and docile (can hold it in your hand). I see them on the side of my house and found the one in the pictures in my garage (@ 50F !). We originally were affraid they were Asian long horned beetle but obviously they are not. Can you identify?
Paul
eastern Massachusetts

Western Conifer Seed Bug
Western Conifer Seed Bug

Hi Paul,
With the onset of winter, the number of identification requests we receive for Western Conifer Seed Bugs increases as they seek shelter indoors to escape the cold.  They are harmless, and they will hibernate through winter, producing a new generation in the spring.

Letter 12 – Western Conifer Seed Bug

 

Fall and over winter visitor
January 16, 2010
I have an insect that is probably 1/2 in long not including the head. It has a rusty color (the wings?) and white lines on the sides under the wings. It seems to be found near my slider to the deck. It also finds its way upstairs. It can makes a low buzzing noise when it clumsily flies around like a helicopter. It’ss slow and easy to catch. I just started to see them with the cooler weather in November and now in January continue to see them. What should I do with them? I don’t like to harm bugs. It has six legs. Here’s one at my blog http://naturalworlds.blogspot.com.
Can we co-exist? Will it eat my house that is mostly wood? Thank you in advance. Your site is wonderful.
tess
northeast USA

Western Conifer Seed Bug

Hi tess,
WE have posted several photos of the Western Conifer Seed Bug, Leptoglossus occidentalis, in the past week.  This harmless Leaf Footed Bug often seeks shelter indoors when the weather turns cooler.  It will not harm your home, its furnishings, nor its inhabitants.

Thank you very much. That is indeed my bug!  I won’t be in a hurry to throw them out the door into the cold since, according to what I’m reading, they will let themselves out in the spring.
Thanks again,
teresa

Letter 13 – Western Conifer Seed Bug

 

Is this a type of Giant Twig Wilter bug?
May 1, 2010
Hey,
I found this really weird looking bug on the beach today, it looked like it was African or something, not belonging originally from the USA….so I found your website and I saw a photo of a Giant Twig Wilter bug and it seems similar to that bug…can you please help me I am so curious to see what bug this is and where it possibly came form and originated. Thanks!
Camille
Robert Moses State Park Beach – Long Island, NY USA

Western Conifer Seed Bug

Hi Camille,
You have astute powers of observation.  This Western Conifer Seed Bug is a Leaf Footed Bug or Big Legged Bug in the family Coreidae, the same family as the Giant Twig Wilter.

Letter 14 – Western Conifer Seed Bug

 

I suspect its a borer of some kind…
Location: Merrillville, Indiana
March 21, 2011 5:24 pm
Hello Mr. Bugman, I was wondering if you could help me identify this bug. I suspect it might be a borer of some kind. I found him climbing up the window today. Thank you so much! And thank you for your wonderful website!!!
Signature: Merrillville Lady

Western Conifer Seed Bug

Dear Merrillville Lady,
You found a Western Conifer Seed Bug.  We have tagged this species as one of our Top 10 identification requests because Western Conifer Seed Bugs often enter homes as the weather cools.  They hibernate indoors and become active again in the spring.

Letter 15 – Western Conifer Seed Bug

 

What kind of beetle is this?
Location: Sheffield, Massachusetts, The Berkshires
March 31, 2011 11:02 am
Hi…
I’m having a lot of fun on your page and I’m wondering if you can help me identify a beetle.
A few times a year, my girlfriend and I visit a friend’s country home in the Berkshires region of Western Massachusetts. In the summer, it’s mosquito CRAZY there. But in the colder months, there seems to be a migration of beetles into the house.
They are upstairs. They are downstairs. They are in the shower. We wonder what they could find to eat in the upstairs bedrooms.
They don’t bother us too much although we are sure to keep our suitcases shut tight. Occasionally, we’ll pick them up with a tissue and place them outside. I do wonder if we are sending them to die in the cold.
We don’t live there, so we’re not too concerned. But…if we did, what do you suggest would be the most humane way to deal with a beetle invasion like this one?
I’m sorry the photos aren’t more clear. They were taken with my phone camera.
Thanks much for any information you can share about these little creatures!
Signature: Todd from Brooklyn

Western Conifer Seed Bug

Hi Todd,
This is a Western Conifer Seed Bug, not a beetle.  The Western Conifer Seed Bug,
Leptoglossus occidentalis, is native to the Pacific Northwest, but beginning in the 1960s, it began to appear in Eastern States and Canada.  In the early 21st Century, there were reports from Northern Europe.  It is unclear exactly how the range of the Western Conifer Seed Bug began to expand, but your letter brings up an interesting possibility.  Western Conifer Seed Bugs often enter homes as the weather cools so that they can hibernate.  You mention keeping your suitcase shut tight.  It is entirely possible that the range of the Western Conifer Seed Bug increased due to tourism by hitchhiking in luggage.  We do not give extermination advice.  Placing the beetles outside is not, in our mind, inhumane.

Hey Daniel,
Thanks again for all the good info.
They sure do like to come inside!
And I’m happy to say, I haven’t spotted any back
in my apartment in Brooklyn.
Thanks for all the good bug information!
With appreciation,
-todd

Letter 16 – Western Conifer Seed Bug

 

Not uncommon around these parts
Location: New Hampshire, USA.
November 13, 2011 10:04 pm
I keep finding these bugs in my room, usually on the floor, but sometimes I find them near a blue lamp I have on a five foot shelf (they could climb up to it, I’m sure). My mother thinks that they are ’wood bugs’. I believe that they could be attracted to the wood, since half of our house is hard-wood floored and we have a wood stove (that means wood inside!). They appear all over the house, but I find them in my room the most. My room is one of the ones that has hard-wood flooring.
I’ve held the little buggers before! They don’t bite. They remind me of a caterpillar, how they just crawl around without harming me. My dogs find them and eat them sometimes, they’re just fine.
Sorry it’s a lot of info, but I should add that our house is not particularly clean, and my room is the worst of the bunch.
Signature: Youngster

Western Conifer Seed Bug

Dear Youngster,
Even though your photo is terribly blurry, there is enough detail to identify the Western Conifer Seed Bug,
Leptoglossus occidentalis, thanks to your thorough description.  The Western Conifer Seed Bug is native to the Pacific Northwest, but it expanded its range to include most of the northern portion of the western hemisphere beginning in the 1960s.  This range expansion might be due to both global warming as well as accidental introduction because of increased travel.  In the early years of the 21st millennium, Western Conifer Seed Bugs were introduced to Europe where they have naturalized.  Western Conifer Seed Bugs are frequently noticed as cool weather sets in because adults seek out shelter, including homes, as places to hibernate.  Western Conifer Seed Bugs will not damage your home, its furnishing nor its inhabitants.

Letter 17 – Western Conifer Seed Bug

 

Please help identify this bug
Location: Aurora, Colorado
November 13, 2011 10:08 pm
I have found 2 of these in the past week, and have never seen them before now. One was in our shower. The 2nd was on a wall.
Signature: Janet

Western Conifer Seed Bug

Hi Janet,
We just finished posting another letter with a Western Conifer Seed Bug.

 

Letter 18 – Western Conifer Seed Bug

 

What is this bug?
Location: nova scotia, canada
December 11, 2011 9:07 am
Dear bugman,
In the last 4 years this bug has appeared in the area of my parents house. In the fall it tries to enter the house. There are dozens trying to get in. We find them all winter. My parents have lived there for 30 years and they were never there before. When threatened they emit a bad odor.
Signature: Regards, Nick Legge

Western Conifer Seed Bug

Hi Nick,
This is a Western Conifer Seed Bug, and it is a benign creature that will not harm your home or its inhabitants.  Western Conifer Seed Bugs attract the most attention in the fall months when they are mature and seek shelter, often inside homes, where they hibernate until spring.

Letter 19 – Western Conifer Seed Bug

 

Ugly Bug
Location: Central New York State
February 17, 2012 6:05 pm
Lately we have seen a few of these ugly bugs inside of our house. We live in Central New York State (Syracuse Area). The weather has been mild this winter but the daytime temperatures are in the low 30’s. The bug does not try to hard to escape just before I kill it. If it can fly I have not seen them do so. This one was on the bathroom wall. Usually seen in late afternoon or evening and they seem to be here quite often (two to three times a week). Help if you can with ID. You may have to blow these pictures up to get a good view. The ugly bug appears to be about 1 inch in length. Thank you
Signature: Herb Moore

Western Conifer Seed Bug

Hi Herb,
This is a Western Conifer Seed Bug and it commonly enters homes when weather cools.  It will not harm your home.

Letter 20 – Western Conifer Seed Bug

 

Subject: what’s this annoying fella?
Location: Northwest montana
September 18, 2012 8:52 pm
This bug is somewhat of a plague in our nice cabin in the woods of Montana. They live inside and outside and we can’t figure out where they’re coming from or how to get rid of them.
Signature: confounded in the cabin

Western Conifer Seed Bug

Hi confounded in the cabin,
This is a Western Conifer Seed Bug,
Leptoglossus occidentalis, and other than being an annoyance, it will not harm you or your cabin.  Western Conifer Seed Bugs often seek shelter indoors when the weather begins to cool so they can pass the winter in hibernation.  They feed upon juices from the cones of conifer trees.

Letter 21 – Western Conifer Seed Bug

 

Subject: Infestation
Location: Catskill MOuntain – Ulster County, NY
September 26, 2012 4:22 am
These are gathering all over my house – inside and outside. Just checked the guest room and they look like a wallpaper pattern on the wall – is this like the ladybug’s attraction my house – something about pheromones or something? Thanks – I’m a fly fisherman and have book marked your site.
Signature: Marc Silag

Western Conifer Seed Bug

Hi Marc,
This is a Western Conifer Seed Bug,
Leptoglossus occidentalis.  Since the 1960s, they have greatly expanded their range from the Pacific Northwest to include much North America in the northern latitudes.  They have also spread to Europe.  Western Conifer Seed Bugs will enter homes to hibernate when the weather cools.

October 18, 2012
If I never expressed my thanks to you for helping the ID of those Western Conifer Seed bugs in my house, I do so now.
Much easier to handle a household pest once you know what they can and cannot do.
ms

Thanks so much for writing back Marc.  We had a tough day and your kindness is much appreciated at this point.

Letter 22 – Western Conifer Seed Bug

 

Subject: Martha’s Vineyard bug
Location: Martha’s Vineyard, MA
October 7, 2012 1:17 pm
I photographed this on Martha’s Vineyard on Oct. 6, 2012. It was a sunny day, about 70 degrees F.
Signature: Gary

Western Conifer Seed Bug

Hi Gary,
This is a Western Conifer Seed Bug,
Leptoglossus occidentalis, and we have been getting at least one identification request per day despite not posting any new images lately.  Your photo is exceptional, so we are creating a new posting.  The Western Conifer Seed Bug is native to the Pacific northwest, but beginning in the early 1970s, it began to increase its range, most likely through accidental human intervention.  The Western Conifer Seed Bug is now found across the northern portion of North America in Canada and the northern states.  In the early 2000s, it also was introduced to Europe where it is spreading.  This is one of our most common identification requests when the weather cools as the Western Conifer Seed Bug will enter homes to hibernate.  It is not considered a threat to people, pets or homes, and it feeds on fluids from the seeds of conifers, so it doesn’t do any harm to the trees themselves either.  It is considered a nuisance when there are high population densities of Western Conifer Seed Bugs.

Thanks for the quick response and the kind words about the photo.

Letter 23 – Western Conifer Seed Bug

 

Subject: Are leaf-footed bugs invasive?
Location: Dover, NH
October 26, 2012 12:03 pm
Hi, It is autumn in New England, so that means the office at my work is buzzing with leaf-footed bugs. Are they native or are they invasive?
Love your site!
Thanks,
Linda
Signature: Linda

Western Conifer Seed Bug

Dear Linda,
Many Leaf Footed Bugs are native to your part of the country, however this species, the Western Conifer Seed Bug,
Leptoglossus occidentalis, is not one of them.  The Western Conifer Seed Bug is native to the Pacific Northwest, and sometime in the 1960s, it began to expand its range across the continent.  It is unclear if this was a natural range expansion or if the Western Conifer Seed Bug was transported by people, though we suspect the latter to be the case.

Letter 24 – Western Conifer Seed Bug

 

Subject: Face of Jesus on a bug?
Location: Jerome, AZ
November 18, 2012 11:37 pm
My neighbors think this is a hualapi tiger (assassin bug) but it appears to have more of a pointy nose than a cone nose …
My house has captured lots of these on all of its windowsills so I hope they do not bite 😉
And there is the cool face of Jesus on its back … Perhaps I can charge admission.
Signature: knitz

Western Conifer Seed Bug

Dear knitz,
This is a Western Conifer Seed Bug,
Leptoglossus occidentalis, a species native to the Pacific Northwest that began to expand its range greatly beginning in the 1960s.  It is unclear how much of that range expansion is natural and how much has been aided by the increase in travel among humans.  We have never had anyone anthropomorphize the markings on the Western Conifer Seed Bug, but we will concede that there is the resemblance of a face on this particular individual.  Since we will be out of the office for Thanksgiving, we are postdating your submission to go live later in the week during our absence.

THANKS for the quick reply … All of the ones at my house have the *face*
Again, thanks for the great site 😉
erica
Knit 1 Bead 2
Jerome, Arizona

Letter 25 – Western Conifer Seed Bug

 

Subject: A grasshopper mated with a stink bug?
Location: Pittsburgh, pa
March 9, 2013 7:19 pm
Found this big in my bathroom and I’m curious what it is because I’ve never seen it before.
Signature: Sean

Western Conifer Seed Bug
Western Conifer Seed Bug

Hi Sean,
This Western Conifer Seed Bug,
Leptoglossus occidentalis, is classed in the same insect order as a Stink Bug, but it is in the Big Legged Bug or Leaf Footed Bug family Coreidae, which is most likely the reason you thought a stink bug mated with a grasshopper.

Letter 26 – Western Conifer Seed Bug

 

Subject: what is this guy?
Location: Tacoma, WA
October 9, 2013 4:19 pm
Found a cool bug. What is it?
Signature: Michelle

Western Conifer Seed Bug
Western Conifer Seed Bug

Dear Michelle,
This is a Western Conifer Seed Bug,
Leptoglossus occidentalis, and you can compare your photo to this individual on BugGuide.  You have provided one of the only images of the Western Conifer Seed Bug in our archives that was sighted in its natural range, the Pacific Northwest.  At some point in about the 1950s, there was a major range expansion, perhaps due to human intervention, and the Western Conifer Seed Bug is now found in many parts of North America according to the BugGuide data.  In the late 20th Century, it was introduced to Europe where it is now established.  We get numerous reports when cooler weather sets in because the Western Conifer Seed Bug seeks shelter from winter weather by hibernating indoors, so they enter homes.  See BugGuide for more information.

Letter 27 – Western Conifer Seed Bug

 

Subject: What is this bug?
Location: Indiana
October 10, 2013 2:37 pm
We found this little bug in our indoor plant store and cannot figure out what it is.
Signature: Planted Inc

Western Conifer Seed Bug
Western Conifer Seed Bug

Dear Planted Inc,
Western Conifer Seed Bugs like this frequently enter homes to hibernate when the weather turns cooler.

Letter 28 – Western Conifer Seed Bug enters home

 

Subject: What is this
Location: London, Ontario, Canada
December 6, 2015 8:07 am
This bug can fly. Have no idea where it came from or what it is but we’ve had 4 of these in our home in the last month. 3 of which were in the last 2 weeks. They were first seen outside in the back yard then they started appearing in the house. We generally don’t keep flowers in the house, the ones in the picture are a birthday gift for my daughter so I’m positive I can rule that out as an attraction for this bug.
We are in London, Ontario, Canada.
The first time we’ve seen one of these guys would have been the back yard back in the summer so temperatures would have been in the 20C and upwards.
Current outdoor temperature is on average approx 2 – 10 C.
Signature: Rob

Western Conifer Seed Bug
Western Conifer Seed Bug

Hi Rob,
This Western Conifer Seed Bug is native to the Pacific Northwest, but beginning in the 1960s, it expanded its range, probably helped by increased human air travel, across North America.  Western Conifer Seed Bugs seek shelter indoors to hibernate when the weather cools.  It will not harm you or your home, but large number indoors may be a nuisance.

Letter 29 – Western Conifer Seed Bug enters home

 

Subject: Who is this dive-bomber?
Location: White Mountains, NH
December 19, 2015 5:30 pm
This fellow has been chasing me around the house for a couple days. He’s a bit over an inch long (two inches including legs), with a hexagonal body — tan with darker brown markings if you can catch him without too much backlighting. He seems to be attracted to bright lights — the glass door in the daytime, electric lights at night. He seems to prefer flying to scurrying, though he’ll walk very slowly across a surface (spent several hours exploring the french doors), and doesn’t remain airborne for more than 10-15 seconds at a time.
Signature: Harassed in New Hampshire

Western Conifer Seed Bug
Western Conifer Seed Bug

Dear Harassed in New Hampshire,
Theoretically, this Western Conifer Seed Bug is not a native species for you in New Hampshire as it is native to the Pacific Northwest, but beginning in the 1960s, there was a significant range expansion which we personally believe is related to increased air travel for Americans.  The Western Conifer Seed Bug can now be found in much of North America and it has been reported from Europe as well.  We can conclude that the European immigration is NOT a natural range expansion.  Western Conifer Seed Bug reports tend to peak in the fall because the insects are fully grown, have developed wings that allow them to fly, and they are seeking to hibernate to escape severe winter conditions.  They seek shelter indoors, just like your individual, and that makes them more visible.  The Western Conifer Seed Bug will not harm you or your home, but if they are numerous, they can be an annoyance.

Daniel, thank you for the identification and additional information!

Letter 30 – Western Conifer Seed Bug enters Home

 

Subject: Beetle
Location: North Dakota
October 12, 2016 11:25 pm
Found crawling in the house. Would like to know if they are poisonous as I am an avid reptile collector and breeder and they may be attracted to my bioactive vivariums.
The grid is a cutting mat with 1/2″ squares marked.
Signature: Bee Green

Western Conifer Seed Bug
Western Conifer Seed Bug

Dear Bee,
This is a Western Conifer Seed Bug, a species that frequently enters homes to hibernate when the weather begins to turn cold.  To the best of our knowledge, they are not poisonous.

Letter 31 – Western Conifer Seed Bug enters home

 

Subject:  Found in kitchen
Geographic location of the bug:  Sullivan county NY
Date: 01/26/2018
Time: 08:00 PM EDT
Your letter to the bugman:  I don’t know what this bug is.
How you want your letter signed:  Nancy Heller

Western Conifer Seed Bug

Dear Nancy,
Western Conifer Seed Bugs like the one you submitted often enter homes when the weather cools so that they can hibernate.  Western Conifer Seed Bugs, though a nuisance, do not pose any threat to your home or furnishings, and they will not harm you or your pets.

Letter 32 – Western Conifer Seed Bug enters cabin

 

Subject:  Strange bug in cabin
Geographic location of the bug:  Vermont
Date: 02/13/2018
Time: 04:20 PM EDT
Your letter to the bugman:  Can you ID THE BUG IN THE PHOTO?
How you want your letter signed:  Ken Petretti

Western Conifer Seed Bug

Dear Ken,
The Western Conifer Seed Bug is an insect with well documented behavior of entering homes when the weather cools so it can hibernate.  Native to the Pacific Northwest, the Western Conifer Seed Bug has greatly expanded its range in the last 50 year.

Dear Daniel,
Thank you very much. We were/are concerned as our grand children visit our cabin often.
I looked at your link which provided additional information.
What would you suggest the best way to contain and eliminate these bugs?
Thank you,
Ken
They are not dangerous.  We do not provide extermination advice.

Letter 33 – Western Conifer Seed Bug enters Home

 

Subject:  Bug identification
Geographic location of the bug:  Newton, Ma
Date: 04/09/2021
Time: 12:11 PM EDT
Your letter to the bugman:  Hi, we have found one of these bugs inside the house every few weeks.  Slow moving, sitting on the wall (or today, on the headboard).   We catch and have put outside but would like to know if they are pests or not!
How you want your letter signed:  Bernard

Western Conifer Seed Bug

Dear Bernard,
This is a Western Conifer Seed Bug, a species native to the Pacific Northwest.  Sometime in the 1960s, perhaps an early indication of global warming or possibly due to increased human travel, the Western Conifer Seed Bug began to expand its range and it is now quite common in the eastern portions of North America.  The Western Conifer Seed Bug seeks shelter indoors to hibernate and most of our requests come from folks like you who find them in the home.

Authors

    by
  • Bugman

    Bugman aka Daniel Marlos has been identifying bugs since 1999. whatsthatbug.com 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.

35 thoughts on “Western Conifer Seed Bug in House: Quick Solutions for Removal”

  1. I wanted to comment on this bug. I live in Ct as well in an apt complex and my apt has tons of them in there. They fly and are near windows and tend to go near the lamps. I complained to the apt office several times they told me that their is nothing to get rid of them with and they would have to seal up cracks and any a/c units. They come in near winter and come from pine trees. I hate them any other assistance on this would be great.

    Reply
  2. I’m also from CT and am experiencing my first fall with these bugs. The first one I found in my bathroom late at night, it got a trip down a toilet, but not before spraying that awful smell. I didn’t bother to find out what it was then.
    ………………………………………………….
    Tonight I had another encounter, though this one was unseen. My boyfriend and i were watching tv and all of a sudden we heard an insect thrashing around. Then the smell hit me, and I instantly recognized it. Boyfriend didn’t smell anything, so I tried to describe it. It smelled like an unripe banana peel, and he recognized it then. Decided to find out what it was this time, and after a bit of googling I found out it was this guy.
    —————————————–
    Just wish I knew where tonight’s invader went. Now I know its not harmful, but I’d rather not have it getting spooked and spraying regularly.

    Reply
  3. I live in Strafford County New Hampshire. We live on a river and are surrounded by pine trees. This year, much more then past years, we are experiencing a pest problem with the Western Conifer Seed Bug. What is effecting them this year particularly, AND what is that pungent smell they emit when you disturb them?
    Thanks ahead!

    Reply
    • Insect populations move in cycles. This is just a year when the Western Conifer Seed Bugs are plentiful. Many Hemipterans, not only Stink Bugs, can emit odors.

      Reply
  4. I caught one of these Western Conifer Seed Bugs on my Jade Plant. Creemore, Ontario, Canada (close to Georgian Bay). Strange thing to find in my house in the middle of winter.
    Your site is a great source for insect identification.
    Thanks

    Reply
  5. I found one of these guys on one of my flowers and took a picture of it. I live in Northern Ohio and have lived here for 56 years and have never seen one before. I do have several pine trees around in the neighborhood. Love your site! I have been here a few times to identify critters. I was going to post a picture I took of him, but am not sure how to do it

    Reply
  6. I have had these in my home every Spring and every Fall for the last 4 to 5 years. I am invaded with them. They are everywhere and do find them in my hair or on me at times. The most frightening of was on one morning I was awakened with a pinkish one on the edge of my mouth. I had to pull to get it off and it left a big blister-like sore that took a week to heal. I wished I could get them out of my home. I catch them and keep them in a covered jar until they have expired. So, I do not think they are harmless. Sorry to disagree….my personal opinion.

    Reply
    • I’m truly sorry of your experience with this bug.
      I do have them also in the winter season…but maybe one
      at the time. I never had a problem with it.

      The blister on your month could be also cold sore…
      since this bugs do not bite.

      Reply
    • I’m truly sorry of your experience with this bug.
      I do have them also in the winter season…but maybe one
      at the time. I never had a problem with it.

      The blister on your month could be also cold sore…
      since this bugs do not bite.

      Reply
    • If you want to keep Western Conifer Seed Bugs from entering your home, you need to understand why they are entering and how they are gaining access. They enter homes to provide shelter from the elements, and they are able to enter homes through cracks in the foundation, gaps in windows and doors, and even simultaneously as people come and go through open doors. You can make your home inhospitable by keeping the indoor temperature the same or lower than the outdoor temperature, though that would not help much for the human inhabitants. You can have your house hermetically sealed, but that could get costly. You will most likely never be able to keep them out with 100% assurance, but you can at least weatherproof your windows and doors and check for cracks in the foundation. That will have the added benefit of keeping your heating and cooling costs down.

      Reply
  7. How does this bug enter your home? Can they come up through the drains. [Most of the ones I find are near the kitchen of bathroom sink.]

    Do they do damage to coniferous trees?

    Reply
    • We are relatively certain that Western Conifer Seed Bugs do not enter homes through drains. They do not harm trees, but they will affect the viability of the cones. According to the Penn State Entomology website: “This true bug of the family Coreidae feeds mainly on the seeds and developing cones of several species of conifers and their respective hybrids.”

      Reply
  8. How does this bug enter your home? Can they come up through the drains. [Most of the ones I find are near the kitchen of bathroom sink.]

    Do they do damage to coniferous trees?

    Reply
  9. I can back these people from New England with regards to this bug. I have a jar that I capture these bugs in and they are definitely this bug! I can submit a pic of five of them. They are gross, and if you step on them they smell bad!!!

    Reply
  10. I have been finding a lot of Western Conifer Seed Bugs inside my home in Mid Michigan area October and they scare me to death, do they bite? what is their purpose in my yard, why are they trying to get into my home? How do I get rid of them?? Any info will be helpful, thank you.

    Reply
    • Western Conifer Seed Bugs, an invasive species in Michigan, do not bite. They enter homes to hibernate when the weather cools. We do not offer extermination advice.

      Reply
  11. I have found a couple of these bugs in my house in upstate NY this weekend. I scooped them up with a paper towel and placed them outside- don’t like to kill anything unless it’s a parasite or super destructive like EAB. And yes they fly.

    Reply
  12. Have been removing a number of these beetles from inside, the basement mostly and now in the kitchen. Our home is surrounded by Norway Spruce with large cones. Anything we can do to make their visit less desirable? We also get the stink bug in early fall. I also meant to comment we live near Toronto ON

    Reply
  13. I keep finding more of these bugs in my house. I am freaking. Someone told me it’s a kissing bug? Maybe you can help. Thank you very much

    Reply
    • Western Conifer Seed Bugs are classified in the same order as Kissing Bugs, so they share some similar anatomical features. Western Conifer Seed Bugs do not pose a threat to humans.

      Reply
  14. Mr. Bug Man, does the Western conifer seed bug have a dangerous bite if disturbed. my wife was bitten by one and it was very painful

    Reply
  15. I’m concerned that what I think are the conifer seed bugs are kissing bugs which I’ve read can spread disease. Twice I’ve awoken to one crawling on me. How do I tell the difference? They were ALL OVER the outside of my house this past fall and have gotten into the house. I’m still finding them but not in such numbers. They make a buzzing noise when flying and stink when I squish them. Can you help me to correctly identify them?

    Reply
  16. I have lived in NE my entire life (over 40) and I have not come across these until this year and I have found about 20 of them so far in and around our house this fall. Do these bugs cause any damage (e.g., like the powder post beetle etc.)? Thank you!

    Reply
  17. I found one in my bathroom also on the toilet, however, I live in the UK so totally baffled how it got here. I’d been in the bathroom a lot that day doing repairs & it just appeared after I left the room.

    Reply

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