Tennessee is home to only one true hornet species, the European hornet, but a second species commonly called the bald-faced hornet also lives throughout the state. A few other large wasps are frequently mistaken for hornets as well. Knowing which is which helps you gauge the actual risk when you spot a big, buzzing insect near your home.
European Hornet
The European hornet (Vespa crabro) is the only true hornet established anywhere in the United States, and it’s well established across Tennessee. Workers reach about an inch long, while queens can hit 1.3 inches, making them one of the largest wasps you’ll encounter in the state. Their coloring is distinctive: a red and yellow head, a reddish-brown thorax, and a brown-to-yellow abdomen marked with brown teardrop-shaped spots. That warm, rusty coloring sets them apart from the black-and-yellow pattern most people associate with wasps.
European hornets prefer to nest inside protected cavities, especially hollows in large standing trees. You’ll also find them in wall voids of houses, attics, and occasionally underground. Because they favor tree cavities, they’re most common in forested areas and wooded suburbs with mature trees. Their nests are made of papery material and can grow quite large inside these enclosed spaces, sometimes going unnoticed until the colony is well established.
These hornets are active at night, which is unusual among stinging insects. You may see them buzzing around porch lights or exterior fixtures after dark. They’re not typically aggressive away from the nest, but they will defend a colony vigorously if you get too close or disturb the entrance. They can also strip bark from trees and shrubs, which sometimes alarms gardeners.
Bald-Faced Hornet
Despite the name, the bald-faced hornet is technically an aerial yellowjacket, not a true hornet. But because nearly everyone in Tennessee calls it a hornet, and because it looks and behaves more like one than a typical yellowjacket, it deserves a full section here. Workers are black with bold white markings on the abdomen and face, and those large white facial patches are the easiest way to identify them. Workers measure roughly five-eighths to three-quarters of an inch, with queens just over an inch.
Bald-faced hornets build the iconic large, gray, football-shaped paper nests you see hanging from tree branches, eaves, and overhangs. Inside, the nest contains stacked layers of comb surrounded by several layers of papery carton, with the entrance hole near the bottom. A mature nest can be bigger than a basketball by late summer.
These are among the most defensive stinging insects in Tennessee. Workers swarm out aggressively when the nest is disturbed, and each one can sting repeatedly. The pain is immediate and sharp, and the soreness, swelling, and itching can last for days. If you spot one of their nests on your property, give it a wide berth.
Large Wasps Often Mistaken for Hornets
Several wasps in Tennessee are big enough to be confused with hornets, and the most common case of mistaken identity involves the eastern cicada killer. Females can reach nearly two inches long, making them larger than any actual hornet in the state. They have a dark orange head and thorax that fades to black on the abdomen, with three light yellow stripes and an orange tinge to the wings and legs.
Cicada killers look intimidating, but they’re solitary wasps, not social ones. Females dig burrows in dry, sandy soil in sunny spots, dragging paralyzed cicadas underground as food for their larvae. Because they don’t have a colony to protect, they’re far less defensive than hornets. Stings are rare and almost always happen when someone steps on one barefoot or grabs it by accident. Males will buzz around aggressively but have no stinger at all.
Southern yellowjackets are another source of confusion. They share the yellow-and-black color scheme of European hornets but are noticeably smaller, topping out around half an inch. They typically nest underground or in wall voids and are far more likely to show up uninvited at a picnic. If the insect harassing your food is compact, bright yellow and black, and under an inch long, it’s almost certainly a yellowjacket, not a hornet.
When Hornets Are Most Active
Hornet colonies in Tennessee follow a predictable annual cycle. Queens emerge from overwintering in spring and start building small nests alone. Through June and July, the colony grows as workers hatch and take over foraging and nest expansion. By August and September, nests are at peak size and the colony is at its most defensive. This is when you’re most likely to stumble across a mature nest and most likely to have a bad encounter.
Activity ramps up further in late summer and early fall as colonies produce new queens and males. Workers become more aggressive during this period because they’re competing for dwindling food sources before the first frost kills them off. Only newly mated queens survive the winter, hidden in leaf litter, bark, or sheltered crevices. The old nest is never reused the following year.
What To Do About a Nest
If you find a hornet nest on your property, the most important thing is to leave it alone until you have a plan. Disturbing a nest, even slightly, can trigger a mass defensive response. For nests larger than a fist, or any nest near a doorway, play area, or high-traffic spot, professional removal is the safest option. This is especially true for bald-faced hornet nests, given how aggressively they defend their colonies.
Small nests discovered early in spring, when the queen is still alone or has only a few workers, are much easier to deal with. But by midsummer, a mature colony can contain hundreds of workers, and the risk of multiple stings rises sharply.
Handling a Sting
A normal sting reaction includes sharp, immediate pain followed by redness, swelling, and itching around the site. These symptoms typically peak within a day or two and fade over the next several days. To manage a sting at home, wash the area gently with soap and water, then hold a cold, damp cloth or ice pack on it for 10 to 20 minutes to reduce swelling. An over-the-counter antihistamine can help with itching, and a nonprescription pain reliever takes the edge off the soreness. Calamine lotion or hydrocortisone cream applied to the skin several times a day also helps.
Watch for signs of a serious allergic reaction: difficulty breathing, swelling of the lips, face, or throat, dizziness or fainting, a rapid weak pulse, hives spreading beyond the sting site, or nausea and vomiting. These symptoms can appear within minutes and require emergency medical care. People with known insect sting allergies should carry an epinephrine auto-injector, particularly during peak hornet season from August through October.