This article was published originally on 8/15/2012
The European paper wasp (Polistes dominula) is one of Iowa's newest residents. Its native range is from Europe to China and it is the common paper wasp of Europe. It has been in the U.S. since the 1970s and has rapidly spread across the northern half of the U.S. and British Columbia. See BugGuide for a map of the current distribution based on contributed photos and more photos.
The European paper wasp is very similar to our native paper wasps in appearance and habits. The surest way to differentiate the European paper wasp from native paper wasps is by their yellow antennae. All paper wasps build paper nests in similar areas (under eaves or other places on buildings sheltered from rainfall). The European paper wasps tend to be a bit more urban in their nesting preferences. There are a number of native Polistes species, but the northern paper wasp (Polistes fuscatus) is the species commonly observed in Iowa. For more information on the variety of paper wasps species please see BugGuide.
Like our native paper wasps, the European paper wasps build open-comb nests out of paper. The paper comes from chewed wood or paper. Paper wasps are social and a new queen wasp starts the nest each year. She makes the first combs and produces young that become workers. The workers are females, but usually do not reproduce. Instead they create new combs and help raise their sisters. The colony continues adding more combs and wasps all summer. In the late summer and fall the colony produces males and new queens. These new queens mate with the males and then overwinter in a sheltered area. The following spring the new queen carrying fertilized eggs from the previous fall begins her own nest. The old queen and the workers from the previous year do not survive the winter and nests are normally not reused.
Paper wasps are not very aggressive and often nests go completely unnoticed as the wasps will not react to defend the nest unless it is directly attacked. It is best to leave nests alone if it is not in the way. If a nest has to be treated a wasp and hornet spray can be used. Treat on a cool morning or evening when the wasps will be on the nests and slow to react. Do not attempt this is you are allergic to wasps and be sure to follow all labeled directions.
European paper wasps on their open-comb nest. Note the orange antennae.