Mud Dauber Wasps (Family Sphecidae)

Mud Dauber wasps are not social wasps like Paper wasps. They are in a different family. Many paralyze spiders to provision mud cells built to enclose eggs, larvae and pupae. The mud cells form long clay tubes or large lumps. The wasps are slender; they are shiny black or brown, orange or yellow, with black markings. Many have long slender thread waists.

Like Carpenter bees, there is no protective worker caste; these wasps are not aggressive; they will not sting unless pressed or handled. Mud Daubers place their mud nests in protected places like electric motors, sheds, attics, against house siding and under porch ceilings. So many wasps congregate at the same site to construct the mud nests that later removal of the nests and repainting is often expensive.

Habitat Alteration and Pesticide Application

Mud daubers are killed easily with aerosol contact sprays. Scrape away mud nests, and cover problem areas with a good quality smooth paint. Nesting should be discouraged on porticos and high porches of historically important buildings.

The Giant Hornet Wasp (Vespa crabro)

Technically, this wasp is the only hornet in North America, but it did not originate here; it was introduced from Europe. It is found in the northeastern quarter of the United States; it ranges as far south as North Carolina and Tennessee with scattered sightings extending west of the Mississippi River.

The Giant hornet is reddish-brown and yellow and almost an inch long. It builds its nest mainly in hollow trees, and in wall voids of barns, sheds and sometimes houses. An open window or door is an invitation to hornet workers, and they frequent buildings under construction. Their large combs and envelope are constructed of partially decomposed wood and, like the Eastern yellowjacket, are very brittle. Workers of the Giant hornet capture a variety of insects including bees and yellowjackets to feed their young. Workers also have a habit of stripping bark back from some shrubs - especially lilac. As they girdle the branches, they lick the sap from the torn edge. They will sting humans, and the sting is painful.

Paper Wasps

Yellowjackets, hornets and paper wasps are all in the same insect family, Vespidae. The common Paper wasp with its umbrella shaped nest or single comb best demonstrates the basic building pattern of a colony.

Paper wasp queens, like other Vespid nest mothers, is the lone female reproductive, who begins her nest by attaching a thick paper strand to an overhanging structure. She then builds hollow paper cells by chewing wood or plant fibers (cellulose) mixed with water and shaped with her mouthparts.

When a half dozen cells or so are hanging together, the Queen lays an egg near the bottom of each one. The little white grubs that hatch from the egg glue their rear ends in the cell and begin receiving nourishment in the form of chewed up bits of caterpillars provided by their mother. When they grow large enough to fill the cell cavity, they break the glued spot and hold on their own by their stuffed fat bodies, hanging head down.

Mature larvae, then, spin silk caps, closing off the cell, and molt into pupae. This same larval behavior pattern is followed by yellowjackets and hornets also. All are females. Other than their white color, these Vespid pupae look like adults; they develop adult systems, then shed their pupal skins, chew through their silk cell cap, pump out their wings, and take their place as worker assistants to their mother. (Paper wasp queens and workers are the same size; yellowjacket and hornet queens are larger than their daughters.)

From spring on, the queen lays eggs and the daughter workers feed larvae and expand the comb or nest. They do not eat the protein (insect) food they gather for the larvae but get their energy from flower nectar. Later in the season, some of the larvae develop into males and others will become next year's queens.

The new males and females mate with those of other colonies, and the fertilized females find hiding places under tree bark or in logs and wait out the winter until they can begin their new colony in the spring. The male Vespids die in winter, likewise the nest disintegrates and will not be used again.

Paper wasps nests are often found near doorways and other human activity areas without occupants being stung. Colonies can become problems, but when they do, Paper wasps can be controlled easily.

When attracted to fallen ripe fruit, these wasps sting people who venture into the same area. Colonies in trees, out buildings, hollow fence posts and other protected places are not as easy to control as those from nests on structures.

Paper Wasp Habitat Alteration

• Remove old nests and scrape the point of attachment. This spot is often selected by new queens for attachment of new combs.
• Remove ripe fallen fruit as often as possible.
• Caulk openings in attics, window frames, and around wall penetrations to keep overwintering females out of unused rooms and spaces.

For more information, please select these pages:

About the Bee

The Africanized Honey Bee (the "Killer Bee")

Yellowjackets - Your Uninvited Picnic Guests

Carpenter Bees

Cicada Killer Wasps

Get the Point about Bee Stings