Hornets and yellow jackets are often confused and their names used interchangeably. Though they share similarities and belong to the same broader wasp family, they are distinct stinging insects. Knowing their differences aids in accurate identification and understanding their roles.
Distinct Species
Hornets and yellow jackets are distinct wasp groups within the Vespidae family, which includes social wasps. True hornets belong to the genus Vespa, with the European hornet (Vespa crabro) being common in North America. Yellow jackets are classified under Vespula and Dolichovespula. For instance, the bald-faced hornet, despite its name, is a type of yellow jacket (Dolichovespula maculata).
Physical Distinctions
Visual identification involves several physical characteristics. Hornets are larger, typically 1 to 1.5 inches long, with some up to 2.2 inches. Their bodies are robust and stocky. European hornets display a yellow and brownish pattern with black markings, appearing less vibrant than yellow jackets. Some may also have reddish markings.
Yellow jackets are smaller, 0.5 to 1 inch long. They have striking black and bright yellow coloration, often with distinct black markings creating a banded appearance. Their bodies are smooth, shiny, and have a narrower waist. Both have six legs and two pairs of wings; yellow jackets often fold their wings longitudinally at rest.
Behavioral and Nesting Habits
Behavioral and nesting patterns also distinguish hornets and yellow jackets. Yellow jackets are known for scavenging, especially in late summer and fall when colonies are largest and food sources scarce. They are attracted to human food like sugary drinks, fruit, and meat at picnics. Yellow jackets often build nests in hidden locations: underground in rodent burrows, within wall voids, or other protected cavities. They are aggressive, particularly when disturbed, and can sting repeatedly.
Hornets are primarily predatory insects. Their diet consists of other insects like flies, caterpillars, and crickets, which they hunt to feed larvae. While adult hornets consume sugary substances for energy, they are less likely to scavenge human food. Hornet nests are constructed from chewed wood fibers mixed with saliva, forming a papery pulp. Most true hornets build aerial nests in exposed locations like trees, shrubs, or building eaves, though some may nest in hollow trees or wall voids. Hornets aggressively defend their nests if threatened.