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Today’s Post Unintentionally Published Early

11-30-15 western conifer seed bug IMG_1133In case you missed it last night, here it is!

Roughly 30 years ago Western Conifer Seed Bugs (Leptoglossus occidentalis) started moving east. They are now well established coast to coast. Here in the East they seek shelter during the winter, often choosing to share our domiciles with us. Fear not – though they look fairly menacing, they will do you no harm. Western Conifer Seed Bugs do not bite or sting, and in their semi-dormant condition they do not feed or breed. If you choose not to co-habit with these bugs, be forewarned. When disturbed, they can emit a noxious smell.

In the spring they will vacate your house and feed on the sap of the young cones and flowers of conifers, including Eastern White Pine, Red Pine, Scotch Pine, White Spruce and Eastern Hemlock. Mating takes place, eggs are laid and the young nymphs feed on conifer seeds which they find by detecting the infrared radiation that the cones emit.
These bugs are also called “leaf-footed bugs,” and if you look at their hind legs you will see that a section, the tibia, is flattened. Some species display this specialized leg structure during courtship, and others may use it for defense purposes.

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20 responses

  1. Michele

    Curious, are these also called Stink Bugs, or Potato Bugs?

    November 29, 2015 at 6:24 pm

  2. Nancy Pompian

    A wonderful bug to introduce to children by letting it walk over your hands in its slow way. The children ask soon ask to have it on theirs.

    November 29, 2015 at 6:25 pm

  3. Amy

    It is so funny to me that some people find the smell these bugs emit noxious. My husband and I both think it smells wonderful, like fresh green grass. I wonder if anyone else thinks that.

    November 29, 2015 at 6:40 pm

    • Evergreen Erb

      I always wondered what they were called. I think we just made up the name box elder beetle, which may be something else. They are kind of scary when they are flying around in the house. But they are quite placid when resting. Happy once again to learn something I didn’t know, but was curious about.

      November 29, 2015 at 7:10 pm

  4. Irma Graf

    Aren’t they also called assasin bugs?

    November 29, 2015 at 7:00 pm

    • There are some assassin bugs that resemble them, but they’re a different family.

      November 29, 2015 at 8:04 pm

  5. Carmen VandeGriek

    Good to know! We’ve been seeing them, they are beautiful but was wondering about their origins, knew that they were not native.

    November 29, 2015 at 7:01 pm

  6. Sara DeMont

    I still give them a lot of room😜

    November 29, 2015 at 7:06 pm

  7. Susan

    I love these beautiful bugs and they’ve never tossed their “noxious smell” around me. They are not stink bugs or potato bugs.

    November 29, 2015 at 7:10 pm

  8. Betsy Boo

    I tried so hard to ifind out what they were. When I have time – maybe February – I will try to find my first pictures of them. May 10 – 15 years ago.

    November 29, 2015 at 9:45 pm

  9. L

    Are this bug’s markings what distinguish it from the assassin bug, or are there other differences?

    November 29, 2015 at 11:11 pm

    • Western conifer seed bugs do not bite (assassin bugs do), and assassin bugs don’t have the large, flattened tibia in their hind legs. Assassin bugs also don’t have the light and dark bands on the outer edges of their wings.

      November 30, 2015 at 7:36 am

  10. Daphne

    I’m definitely one of those who finds the smell noxious! Glad to finally have the correct name, as I have just been calling them stinky bugs for years.

    November 30, 2015 at 7:33 am

  11. Don’t want them cohabiting with you? I for one can live without the ” stink ” they emit all over one’s hand if handled incorrectly. There is a simple method that works for me. Grab them by the antennae with your index finger & thumb, if you look closely you will see the stream of ” stink juice ” emitted from the abdomen. Out the door they go! I am not a monk…

    November 30, 2015 at 8:16 am

    • You are a master seed bug handler, for sure!

      November 30, 2015 at 9:07 am

  12. Kathryn

    A friend of mine calls these “sprickets” and so in our house, sprickets they will always be. I think it’s a much better name!! They entertain the cats all winter and are welcome to hang out.

    November 30, 2015 at 9:45 am

  13. micky mckinley

    I asked my son-in-law ( a generally smart guy)
    What’s the deal with infrared radiation in pine cones??
    His response:

    Seed tissues need to remain cool; at high temperatures, key proteins in the cells can degrade. My bet would be that the structure of the cones is an evolved trait that increases dissipation of heat absorbed from the sun, thereby protecting the seeds. The cone scales strongly resemble “radiator fins” (i.e., high surface area and small cross-section), which supports this hypothesis.

    What do you think?

    November 30, 2015 at 11:05 am

  14. Barbara

    Are these bugs in any way destructive to the trees, weakening them by their feeding behavior?

    December 13, 2015 at 10:18 am

    • My understanding is that they do compromise the health of the seeds produced on trees they feed heavily on.

      December 13, 2015 at 12:07 pm

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