Return of the Elm Seed Bug (Arocatus melanocephalus)

Again this summer, we are being attacked by the Elm seed bug.  They are everywhere!  They fly in circles in the garage, they drop down on you when you enter your house, they fly into the mashed potatoes on the table. But, they spend most of their time on my kitchen window, crawling around looking for a way in.  They get in via the very smallest of holes.  They squeeze through the tiny vents in my new double windows. Many enter the house and then die on the window sill.

Elm Seed Bug
Elm Seed Bug (Photo courtesy of ID State Dept of Agriculture)

This winter, we had an invasion of them in our family room and I think it all started with one that entered and I made the FATAL error.  I squished it with tissue and threw it away.  The next day there were 20 in the room, I attacked and squished and killed them all.   The next day, twice as many- in December!

Whatever you do, don't squish these guys!  It attracts more of them to your house.  Apparently, the experts say, they have an odor.  I really can't detect it, but the bugs must because the dead bugs bring in more and more.

Now, I vacuum these bugs up with a shop vac in which I have placed a little bit of soapy water.  The soap suffocates the &^%$#'s. My window sills always have a few dead and a few alive bugs on them.

Elm Seed Bug
Dead bugs sitting on the window sill.

As an experiment, before I left for the weekend recently, I placed a few stems of fresh lavender on the sills. Normally, there would be several bugs crawling on the windows, but when I got back I found very few.  Maybe this lavender thing works.  If it is smells that attract them, then smells can repel them too? Not a scientific experiment, but I really think there is a decrease of these guys in my house.

So excuse me, I am going outside to cut more lavender!

Lavender, one of many strongly fragranced flowers
Lavender, one of many strongly fragranced flowers

And if it's strong fragrances that deter them, try these other stinky ones: Marigolds, catmint, purple salvia


Catmint (nepeta)



Published by Vicki

I love gardening and when it comes to vegetables, organic gardening is important to me. I am an Advanced Master Gardener with the University of Idaho, and my favorite garden activity is pruning. When I'm not cutting down plants, you can find me shooting photos on my Canon DSLR or out smashing overheads on the tennis courts.

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    1. Yes, that was a desperate attempt to stop or slow the bugs from coming into the house. I have to say, it was a FAIL. I noticed no difference at all.

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