Wasps and hornets come in dozens of species across North America and Europe, ranging from half-inch yellowjackets to the two-inch northern giant hornet. Understanding which ones you’re looking at helps you gauge the risk, decide whether a nest needs attention, and appreciate the surprisingly important role these insects play in ecosystems. Here’s a practical breakdown of the most common types you’re likely to encounter.
Yellowjackets
Yellowjackets are the wasps most people run into, especially at outdoor meals. They’re aggressive scavengers drawn to sugary drinks, fruit, and meat, which makes them a frequent nuisance from late summer through fall. Most species measure about half an inch (14 mm), with black-and-yellow banding on their abdomens and yellow legs. Their bodies are smooth and shiny compared to the fuzzier look of bees.
Several species are common across North America. The eastern yellowjacket has a distinctive anchor-shaped marking at the top of its abdomen. The German yellowjacket, now widespread in the U.S., has thick yellow arrow-shaped markings pointing down each abdominal segment. The southern yellowjacket is unusual because queens are a striking orange-brown rather than yellow. The ground hornet yellowjacket is the largest of the group at about three-quarters of an inch (21 mm).
Most yellowjackets nest underground, often taking over abandoned rodent burrows. You might not notice a colony until you accidentally step on the entrance or run a lawnmower over it, which triggers a defensive swarm. Some species, like the aerial yellowjacket, build enclosed paper nests hanging from tree branches or building overhangs instead. Underground nests can house thousands of workers by late summer, which is when encounters peak.
Paper Wasps
Paper wasps are slimmer and longer-legged than yellowjackets, with a noticeably narrow waist and legs that dangle during flight. They’re typically brown or reddish-brown with yellow or orange markings, though coloring varies by species. Their most recognizable feature is their nest: an open, umbrella-shaped comb without any outer covering, attached to a surface by a single stalk. You’ll find these nests under eaves, porch ceilings, deck railings, and inside grills or mailboxes.
Paper wasps are generally less aggressive than yellowjackets. They’ll sting if you disturb the nest directly, but they rarely bother people at picnics or garbage cans. Their colonies are also much smaller, typically a few dozen workers rather than thousands. On the Schmidt sting pain index, a scale running from one to four, paper wasps rate about 1.5. The sensation is described as a burning, throbbing pain, like a drop of superheated frying oil landing on your arm.
Bald-Faced Hornets
Despite the name, bald-faced hornets are technically yellowjackets, not true hornets. They’re larger than typical yellowjackets at five-eighths to seven-eighths of an inch (16 to 22 mm), and their coloring sets them apart immediately: black and white rather than black and yellow, with a mostly white face.
Their nests are impressive structures. They build large, enclosed, egg-shaped paper nests out in the open, often hanging from tree branches up to 60 feet high in the canopy. Nests can also be attached to building walls, overhangs, or utility poles, typically at least three feet off the ground. The nests are light gray, sometimes with gray and light brown stripes, and feature a main entrance at the bottom along with smaller arched openings near the top. A newer nest may have a long entrance tube extending downward. The paper material is made from chewed wood pulp mixed with saliva, forming both the honeycomb-shaped brood cells inside and the protective outer envelope.
Bald-faced hornets are highly defensive of their nests and will pursue perceived threats aggressively. Give any nest you spot a wide berth.
European Hornets
The European hornet is the only true hornet established in North America. It’s large, about an inch long, with a brown-and-yellow striped abdomen and a reddish-brown head and thorax. Unlike most yellowjackets, European hornets are active at night and are attracted to lights, so you might find them bumping against porch lights or windows after dark.
Their nests are tan-brown, relatively fragile, and always built in concealed locations: hollow trees, barns, outbuildings, wall voids, and attics. They’ll also take over abandoned beehives. European hornets are less aggressive than bald-faced hornets unless the nest is disturbed, and they’re actually beneficial predators of grasshoppers, flies, and other pest insects.
Northern Giant Hornets
The northern giant hornet is the world’s largest hornet, measuring 1.5 to 2 inches long. Native to Asia, it was first detected in North America in August 2019 on Vancouver Island, Canada, and has since been found in the northwest corner of Washington State. It has a large, solid yellow or orange head with black eyes, a dark brown or black thorax, and an abdomen with alternating dark brown and yellow or orange bands. The contrast between its bright head and dark thorax is distinctive.
These hornets pose a serious threat to honeybee colonies. A small group can destroy an entire hive in hours. They don’t typically attack people unless they feel threatened, but their sting delivers significantly more venom than smaller wasp species due to their size. U.S. and Canadian authorities have been working to detect and eradicate nests before the species establishes a permanent foothold.
Solitary Wasps Worth Knowing
Not all wasps are social colony-builders. Solitary wasps live alone, rarely sting people, and include some spectacular species. The tarantula hawk wasp, found in the southwestern U.S., hunts tarantulas to feed its larvae. It’s a large, metallic blue-black wasp with orange wings, and its sting tops the Schmidt pain index at a 4 out of 4, described as “blinding, fierce, shockingly electric.” Fortunately, these wasps are docile toward humans and sting only when grabbed or stepped on.
Mud daubers build small tube-shaped nests out of mud on walls and ceilings. They’re slender, usually black or metallic blue, and provision their nests with paralyzed spiders. Cicada killers are ground-nesting wasps nearly as large as the northern giant hornet. Despite their intimidating size, they’re gentle and focused entirely on hunting cicadas. Males may hover near you to investigate but lack stingers entirely.
Why Wasps Matter Ecologically
Wasps are major predators of caterpillars, aphids, flies, and other insects that damage crops and gardens. Social wasps hunt constantly to feed protein to their developing larvae, removing enormous volumes of pest insects over a season. Globally, 164 plant species depend solely on wasps as pollinators. Among these are figs, which in turn support roughly 1,000 tropical bird and mammal species. Wasps also visit a wide range of wildflowers for nectar, including fleabane, boneset, golden Alexander, and New England aster.
What to Do if You Get Stung
Most stings cause pain, redness, itching, and minor swelling around the sting site. This is a normal reaction, and most people feel better within hours or days. If a stinger is left behind (wasps usually don’t leave theirs, but it happens), scrape it out quickly with a fingernail rather than squeezing it, which can push more venom into the skin. Wash the area gently with soap and water, then apply a cold compress. An anti-itch cream and an over-the-counter antihistamine can help with swelling and itching, and a standard pain reliever handles the soreness.
A small percentage of people experience anaphylaxis, a serious allergic reaction that affects multiple body systems at once. Warning signs include hives or rash spreading beyond the sting site, swelling of the lips, tongue, or throat, difficulty breathing or wheezing, dizziness or fainting, stomach pain, and a sudden feeling that something is seriously wrong. These symptoms require emergency treatment immediately, as anaphylaxis can be fatal without intervention. If you’ve had a severe reaction to a sting before, carrying prescribed epinephrine is essential any time you’re outdoors during wasp season.