I get a lot of questions on paper wasps. They are the wasps that make the honeycomb-like nest around the eaves of your house.
A paper wasp queen is the lone female reproductive, who begins her nest by attaching a thick paper strand to an overhanging structure or protective site. She then builds hollow paper cells by chewing wood or plant fibers (cellulose) mixed with water and shaped with her mouthparts.
There are 27 species in North America that are considered semi-social.
When a half dozen cells or so are hanging together, facing downward, 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.
The fact that they feed on caterpillars makes paper wasps beneficial insects, which you want some place close by, but not necessarily on your house. 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.
Paper wasps are not normally aggressive until you disturb their nests. The European paper wasp is far more aggressive than our native paper wasp. This wasp first came to the United States in 1981 and has been found on both the East and West coasts and probably occurs all across the country.
From spring on, the queen continually lays eggs and the female workers feed larvae and expand the comb or nest. Each nest can house a few to several dozen paper wasps. 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 wasps die in winter; likewise the original 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.
There can be up to 100 or more members by August. 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.
Remove old nests and scrape the point of attachment. You can spray the area with Avon’s Skin-so-Soft, as wasps don’t like it.
Remove ripe fallen fruit and garbage as often as possible. Caulk openings in attics, window frames, and around wall penetrations to keep overwintering females out of unused rooms and spaces.
You can freeze the wasps in a nest with a carbon dioxide extinguisher or you can vacuum up all exposed individuals (with 2 tablespoons of cornstarch in the bag) and/or spray with soapy water. If possible wear heavy clothing, gloves and a veil. Proceed cautiously, especially if you must use a ladder.
Fagerlund can be reached by e-mail with pest control questions for this column at [email protected] or by phone at 505-385-2820.
A word on paper wasps – El Defensor Chieftain
wasp nest – Google News