Mud Daubers and Cicada Killers

Harry E. Williams, Professor and Jaime Yanes, Jr., former Assistant Professor,
Extension Entomology and Plant Pathology

Common Name	Scientific Name
Mud Dauber (Black & Yellow)	Sceliphron caementarium (Drury)
Blue Mud Wasp	Chalybion californicum (Saussure)
Cicada Killer	Sphecius speciousus (Drury)

Mud daubers, mud wasps and cicada killers may become a nuisance when they nest around homes and other structures where people live, work and play. In spite of their formidable appearance, these solitary wasps are not aggressive and controls are rarely needed.

Identification

The adult mud wasp is nearly 1 inch long and blackish or iridescent blue-black with bluish wings and a more long and slender waist than most other wasps. The black and yellow mud dauber is blackish-brown with yellow spots and yellow legs. They build finger-like nests of mud attached to flat surfaces under roofs and outbuildings, under eaves, in attics, etc.

The cicada killer is large (1½ inches or more) with a dark brown body and a black abdomen with yellow markings. It nests in the ground, digging galleries in lawns, gardens and flower beds.

Life Cycle and Habits

Solitary wasps are different than the social wasps (yellow jackets, hornets and paper wasps). They have no worker caste and the queens care for their own young. Solitary wasp queens use their sting to paralyze their prey (flies, spiders, caterpillars, cicadas, etc.) rather than to defend their nests. Consequently, these wasps are non-aggressive and rarely sting unless touched or caught in clothing.

Treatment of Stings

If stung, immediately apply a poultice of a meat tenderizer (an enzyme) to the wound. If the sting is not deep, this will break down the components of the sting fluid, reducing pain. Also, a commercial preparation such as a Sting Kill swab can be used. Antihistamine ointments and tablets taken orally appear effective in reducing reaction to stings. However, people who are highly sensitive to stings should consider a desensitization procedure in an allergy clinic and consult their physician about medical kits such as Ana-Kit, which contains antihistamines and aqueous epinephrine (administered by injection), and frequently a bronchodilator material (inhaler).

Control Measures

Usually it is not necessary to control mud daubers and wasps or cicada killers unless they are a nuisance. Sometimes when painting buildings it is necessary to remove the mud tube nests containing wasps. Also, the nesting activity of cicada killers may damage lawns, flower and vegetable gardens, especially when many cicadas are in the area and cicada killer populations are high.

Insecticides: Chemical control should be considered as a last resort, because these wasps are not aggressive and do not sting unless forced to.

Mud dauber nests can simply be removed with a putty knife. Control adult wasps with a fly swatter or a wasp and hornet aerosol spray containing synergized pyrethrins or resmethrin. After using insecticides, scrape away the nest and dispose of it to prevent emergence of developing young and attacks by scavenging dermestid beetles.

Cicada killer wasps will fly near people, but females will not sting unless provoked. Females lay eggs and provide the young larvae with paralyzed cicadas. If control is necessary, locate the nests during the daylight hours (a large amount of soil will appear excavated from each nest). Treat late at night or before dawn when wasps are in their nests and it is cool, ideally less than 60 degrees F. Use a flashlight covered with red cellophane for lighting. You can apply carbaryl (Sevin), bendiocarb (Ficam D) or pyrethrins (Drione) dust into each nest entrance; cover with a handful of moist soil. A can of Whitmire Wasp Freeze is useful.

PRECAUTIONARY STATEMENT

In order to protect people and the environment, pesticides should be used safely. This is everyone's responsibility, especially the user.
Read and follow label directions carefully before you buy, mix, apply, store or dispose of a pesticide.
According to laws regulating pesticides, they must be used only as directed by the label.

Pesticides recommended in this publication were registered for the prescribed uses when printed.
Pesticide registrations are continuously being reviewed.
Should registration of a recommended pesticide be canceled, it would no longer be recommended by the University of Tennessee.
Use of trade or brand names in this publication is for clarity and information; it does not imply approval of the product
to the exclusion of others which may be of similar, suitable composition, nor does it guarantee or warrant the standard of the product.