An Eruption of Box Elder Bugs?

Adult boxelder bug, Pittsburgh, 2017 (photo from Wikimedia Commons)

24 July 2024

July is certainly Bug Season!

Yesterday Mike Fialkovich sent news that it’s a big year for boxelder bugs (Boisea trivittata) where he works in New Stanton, PA.

Huge numbers of box elder bug nymphs, New Stanton, 23 July 2024 (photo by Mike Fialkovich)

There was a big gathering of Boxelder Bugs at my workplace today. Most were nymphs but a few adults were present. I noticed the adults were numerous recently on the side of the building but today the numbers of nymphs were impressive.

— email from Mike Fialkovich, 23 July 2024

I was a little surprised to see the swarms on non-native winged burning bush (Euonymus alatus).

Boxelder bug nymphs on winged burning bush, New Stanton, 23 July 2024 (photo by Mike Fialkovich)

As their name suggests, the boxelder bugs’ host plant is the box elder tree (Acer negundo), which is both native and abundant.

Large box elder tree along the trail at Duck Hollow, Pittsburgh, July 2021 (photo by Kate St. John)
Box elder leaves, Sept 2020 (photo by Kate St. John)

Soon these nymphs will become adults that look like this … and the bug pictured at top.

Adult boxelder bug, Brooklyn, 2024 (photo from Wikimedia Commons)

Have you seen a swarm of boxelder bugs lately? If so, leave a comment and tell me where.

2 thoughts on “An Eruption of Box Elder Bugs?

  1. I’m in Natrona Heights. I saw a mass of boxelder bugs when turning mulch in a back fence garden. Had never seen them before – there were lots of them….very near my big milkweed planting, so could it be their seed pods that interests them?
    These were small – looked them up so i knew what they were, but saw your post today.
    Are they going to be a problem?

Leave a Reply

Your email address will not be published. Required fields are marked *