Elm Seed Bug

Identification

• black and red bug about 1/3 inch long
• triangular segment between the top part of the wings
• triangle is black and surrounded by red on the top portion of the wings (see bottom picture, 2nd bug)
• alternating black and red pattern outside of wings
• red abdomen on underside

Nesting Habits

• found in and around buildings in the spring and fall, especially outdoors where elm seeds have accumulated in the spring
• elm trees

Diet

• elm seeds

Significance

• nuisance: congregate around buildings that have nearby elm trees and elm seeds; can come indoors and annoy occupants
• overwinter in cracks and crevices in buildings
• may stain lightly colored materials and emit an unpleasant odor when smashed
• not a health threat

IPM Recommendations

• Remove elm trees in the area if possible.
• Seal cracks that may allow bugs to enter buildings.
• Vacuum to remove indoor and outdoor populations.
• Remove elm seeds that have collected around buildings.
• Remove elm from tree planting lists.
• Remove volunteer elm while they are small.

For more information, see our Elm Seed Bug fact sheet.