Mud Daubers are Sphecid wasps that are solitary, not social as are honey bees, yellowjackets. These solitary wasps capture prey (spiders, bugs, other insects) which are placed into an individual cell. A mud dauber does not construct cells or nests from paper (salivary solution and wood pulp) as do yellowjackets, hornets and paper wasps, but from mud. During the summer months the Mud Dauber can be seen lighting on the ground at the edge of mud puddles the day after a summer rain. The liquid from the mud puddle is used to build the all too familiar mud cells. These cells (or dirt dauber nests, as some will call them) are built on the exterior of barns, sheds, homes or other structures. These cells can be plastered individually or in rows by a single female wasp. Seeing several cells does not mean you have a colony of mud daubers, since these wasps are not social insects.
A very important part of mud dauber elimination is removal of the cells or nests. In the Mud Dauber Information section, the food source of this wasp is mentioned because of its importance. These wasps are beneficial because they feed on possible pests, bugs, spiders – but the wasps become a pest when they use our homes as a nesting spot. [If there is a large population of Mud Daubers in an area, there is a large population of other bugs and spiders in the same area.]
In elimination of the wasps, their food source has another impact on your home: secondary pest invasion. A deserted mud dauber nest contains the wasp’s prey that was originally captured as food for the young wasp larvae. Certain Dermestid beetles are attracted to the prey, pupal castings and larvae of the wasps. A common pest that invades homes from deserted wasp nests is the Carpet Beetle.
Removing the nests and eliminating the wasps can be done in one step, in most cases. Using your hose-end sprayer, broadcast a solution of Cypermethrin on the exterior of the structure. Liquid concentrates of Cypermethrin (Demon EC,
Cynoff EC) work best. Wasps, bees and hornets do not like Cypermethrin!
Start your application at the top sides of the structure, working your way down to the ground; in this manner you will get the coverage you want without much waste. With good water pressure, your pesticide application should break up and wash off the mud made by the wasps. If not, a long stick should be used to remove all nesting materials. Old mud nests not only look unattractive but can make your home vulnerable to Carpet Beetles or other dermestids that invade homes.
During the summer months you might want to treat the exterior of your home with Demon or Cynoff insecticides, to help prevent re-infestation of wasps and to keep down other pests such as spiders, ants, scorpions, carpenter ants, roaches, centipedes, millipedes – most household pests.