Mud nest? in crawlspace

Asked December 31, 2020, 5:06 PM EST

I found this sitting on the ledge in my crawlspace.
Id like to know if it might be the remains of a nest of a harmful organism. It is about three inches long and an inch and a quarter wide. Seems to be made of dried mud.

Benton County Oregon

1 Response

Hi,

This appears to be a mud dauber (Family: Sphecidae) nest. Pretty common and the nest is usually up against a vertical wall. These insects are very beneficial, as they hunt pestiferous insects and spiders. For more information see this Extension publication: https://extension.usu.edu/pests/schoolipm/structural-pest-id-guide/mason-potter-mud-dauber-wasp

Best,