The insects commonly called wasps and hornets often cause confusion. Both belong to the order Hymenoptera (which includes bees and ants) and are classified within the family Vespidae, known as the “true wasps.” While this shared family means they have common ancestry and similar social behaviors, their differences are significant for identification. Distinguishing them requires examining their classification, physical appearance, and habits.
The Taxonomic Relationship
The fundamental distinction between a hornet and a wasp is rooted in their classification at the genus level. True hornets belong exclusively to the genus Vespa, which includes about 22 species worldwide and represents the largest of the social wasps. Many other common stinging insects, such as yellowjackets, are wasps but belong to different genera, like Vespula or Dolichovespula. Paper wasps, frequently seen building open-comb nests, are classified in the genus Polistes. The name “hornet” is sometimes misapplied to other large wasps, such as the Bald-faced hornet, which is actually a species of yellowjacket (Dolichovespula maculata).
Key Physical Differences for Identification
Hornets are generally larger and noticeably bulkier than most common wasps, such as yellowjackets. While many wasps measure about one inch in length, hornets often reach up to an inch and a half or more, giving them a stocky appearance. A closer look at the head structure reveals that hornets have a broader area behind their eyes, making their heads appear more rounded than those of other wasps.
The shape of the abdomen also provides a reliable visual cue. Most common wasps have a slender and defined connection between the thorax and abdomen, resulting in a narrow “waist.” Hornets possess a wider, more robust, and rounded abdomen, contributing to their overall thicker body shape. Coloration also differs: many wasps feature bright yellow and black stripes, while true hornets often display more muted colors like reddish-brown and white, or black with yellow accents.
Differences in Nesting and Behavior
The nest architecture of hornets and wasps shows distinct differences. Hornets typically construct large, enclosed, football- or tear-drop-shaped nests made from a papery material of chewed wood fibers and saliva. These nests are often suspended high in trees, shrubs, or on structures, and are completely covered, featuring a single entrance hole. In contrast, many common wasps build their nests in cavities, such as underground burrows or wall voids, or they may construct open, umbrella-shaped paper combs hanging from sheltered spots.
Differences in diet and foraging habits impact how they interact with humans. Hornets are highly effective predators, primarily hunting insects like flies and grasshoppers to feed their young, making them less likely to scavenge human food. Wasps, particularly yellowjackets, are opportunistic omnivores and notorious scavengers. They are readily attracted to sugary substances, fruit, and protein-rich human foods like meat in the late summer. This scavenging behavior often brings wasps into closer contact with people at picnics or outdoor gatherings.
Regarding temperament, both insects can sting repeatedly without losing their stinger, but the circumstances of attack vary. Hornets are generally less aggressive unless their nest is directly threatened, at which point they become fiercely protective. Some common wasps, especially yellowjackets, exhibit a higher level of aggression and are more prone to stinging unprovoked, particularly when foraging or their colony is large and nearing the end of its season.