Mud Daubers University of Maryland Extension

Mud daubers are dark, often metallic black or blue wasps. They are not aggressive.

Clay Masters: These Wasps Make Good Neighbors - WALTER Magazine

Home and Garden Information Center

Extension College of Agriculture & Natural Resources at UMD

Mud dauber - Wikipedia

Home and Garden Information Center

Black and Yellow Mud Dauber: Unraveling the Life of a Unique Wasp - What's That Bug?

Scoliid Wasp University of Maryland Extension

Identify and Manage Outdoor Insects

Check out this old nursery of Organpipe Mud Dauber Wasps!

University of Maryland Extension