The European Hornet (Vespa crabro) is the largest hornet species found in both North America and Europe. This social insect is known for its large colonies and its distinct, paper-like nest structure. Understanding the visual characteristics and preferred placement of this hornet’s nest is necessary for identification and safely avoiding conflict.
Distinctive Physical Characteristics
The nest is constructed from a papery material that workers create by chewing weathered wood fibers and mixing them with saliva. This mixture creates a water-resistant, cellulose-based envelope for the colony. The resulting paper is characteristically brownish or tan, often incorporating pieces of bark or decayed wood, which gives the outer surface a mottled or rugged texture.
Unlike the smooth, uniform gray of some other aerial wasp nests, the European Hornet’s nest often appears brittle and messy. Mature nests are generally pear-shaped or oval, sometimes reaching up to two feet in length and 20 inches in diameter. The construction provides a protective shell for the multiple horizontal combs inside. A single nest can house a colony of 200 to 400 workers, though some colonies may contain up to 1,000 individuals by late summer.
Typical Nest Placement and Structure
European Hornets prefer building their nests within enclosed, dark cavities, a behavior that contrasts with many other social wasps. Primary nesting sites include hollow tree trunks, their natural habitat, but they readily use man-made voids. Common urban locations are wall voids, attics, sheds, and sometimes abandoned beehives.
Because the nest is hidden inside a cavity, the structure is rarely visible. Often, the only outward sign is a small, inconspicuous entrance hole where the hornets fly in and out, usually situated six feet or more above the ground. The internal architecture consists of multiple horizontal combs, often stacked in six to eight layers, where the brood is raised. These combs are usually enclosed within the paper envelope, though nests built in protected spaces may lack a complete outer covering.
Differentiating the Nest from Look-Alikes
Distinguishing a European Hornet nest from other stinging insect nests involves observing the material, color, and placement. The nest is often confused with those of the Bald-faced Hornet and various Yellow Jacket species. Bald-faced Hornet nests are typically smooth, gray, and always exposed, hanging freely from tree branches or building overhangs in an inverted teardrop shape. This contrasts sharply with the European Hornet’s brown, rugged paper and hidden cavity placement.
Yellow Jackets also build paper nests, but they typically construct them underground in old rodent burrows or within small wall voids. The European Hornet’s preference for large, aerial, enclosed cavities like hollow trees or attics is a defining difference. The presence of a large, brownish, papery structure concealed within a structural void is a strong indicator of a European Hornet colony.