This solitary, beneficial wasp is found throughout the eastern half of the U.S. and southern Canada. It’s common name is given due to the characteristic look of the mud nests, which consist of elongated cells stacked one on top of or next to another, rather than the solid blob of mud made by the black and yellow mud dauber. Each cell will be provisioned with 3 to 18 spiders and then an egg. Males do not participate in the construction of the cells, but may stand guard near the cells and threaten intruders with a loud buzzing sound. Otherwise these wasps are not aggressive and would sting only if specifically threatened, such as being caught in clothing.
This beneficial wasp should never be harmed. A landscape and home are better off with the wasps than without them, given their nature of preying on spiders.