Paper wasps are perhaps the most common wasps around structures. They are also known as "umbrella wasps" because their nests look like umbrellas hanging upside-down from eaves and overhangs. Common species include the northern paper wasp (P. fuscatus), a black to reddish-brown wasp up to ¾-inch long, and the European paper wasp (P. dominula) which is black and yellow, resembling a yellowjacket.
A paper wasp nest is a single comb of hexagonal cells made of a papery material the wasps form by chewing wood and mixing it with saliva. Larger nests can harbor up to 75 paper wasps including larvae and pupae developing within the cells. To feed the larvae, paper wasps capture insects, especially caterpillars. Late in the year, colonies of paper wasps, yellowjackets and hornets produce new queens that abandon the nest (it will not be reused) and seek shelter for winter. Many find their way into structures and are later seen crawling sluggishly across the floor when temperatures rise in late winter or early spring.