Yellow jackets and hornets are often confused, though they are distinct insects. While both are social wasps, they differ in physical characteristics, behaviors, and nesting habits. Understanding these distinctions can help in accurate identification.
Understanding Yellow Jackets
Yellow jackets are predatory social wasps found across North America. Workers typically measure about 12 mm (0.47 inches), with queens reaching around 19 mm (0.75 inches). Their bodies are black and yellow, featuring alternating bands on the abdomen, though some species may display black and white patterns. They have smooth, shiny bodies and narrow waists, distinguishing them from hairier insects like bees. Yellow jackets also tend to have a rapid, side-to-side flight pattern before landing.
Yellow jackets construct paper nests from chewed wood fibers mixed with saliva. These nests are often built underground in soil cavities, abandoned rodent burrows, or protected spaces like tree stumps, wall voids, or attics. They are known for aggressive scavenging, particularly in late summer and fall, when they are attracted to human food, sweets, and garbage. Yellow jackets are carnivorous, preying on other insects, and can sting repeatedly, making them a significant concern around outdoor activities.
Understanding Hornets
Hornets are the largest eusocial wasps, with most species measuring 1 to 1.5 inches, though some can reach up to 5.5 cm (2.2 inches). They have a more robust and stocky build compared to yellow jackets. While many hornets exhibit yellow markings, their coloration often includes brown or reddish-brown with yellow or yellowish stripes, rather than the vibrant black and yellow of many yellow jackets. Their faces may also appear slightly more elongated.
Hornets build communal paper nests above ground, often in trees, shrubs, or within structures like wall voids, attics, or sheds. These nests can be quite large, sometimes reaching up to 24 inches in diameter. Hornets are predatory insects, primarily hunting other invertebrates to feed their larvae, and are less drawn to human food sources than yellow jackets. They aggressively defend their nests when threatened, and their stings can be particularly painful due to the venom composition.
Key Distinctions Between Them
Key distinctions between yellow jackets and hornets are evident in their appearance, nesting habits, and behavior. Hornets are generally larger than yellow jackets, which are typically half an inch to one inch long. While yellow jackets display bright black and yellow bands, hornets often have more muted tones, incorporating brown or reddish-brown with yellow or white markings. Hornets also possess a more robust build and slightly hairier bodies compared to the smoother yellow jackets.
Nesting preferences also differ significantly. Yellow jackets commonly build concealed nests underground in soil cavities or abandoned burrows, or in protected spaces like wall voids. In contrast, hornet nests are usually found above ground, often suspended from tree branches, shrubs, or attached to buildings, and are frequently visible aerial structures.
Behaviorally, yellow jackets are highly aggressive scavengers, readily attracted to human food and stinging even away from their nest. Hornets, conversely, are primarily predators of other insects, less likely to scavenge, and aggressively defend only their nests.
The Scientific Classification
Both yellow jackets and hornets belong to the same biological family, Vespidae, which includes social wasps. This shared classification contributes to their common confusion. However, within the Vespidae family, they are categorized into different genera.
Yellow jackets are classified under the genera Vespula and Dolichovespula. For instance, the Eastern yellowjacket is Vespula maculifrons, and the bald-faced hornet, despite its common name, is a type of yellow jacket (Dolichovespula maculata). Hornets belong to the genus Vespa, with the European hornet (Vespa crabro) being a well-known example. This taxonomic distinction clarifies that while related, yellow jackets and hornets are not the same insect.