These aggressive pests possess a sting and bite seemingly bigger than their “buzz”. You’ll find the bright yellow and black insects in the backyard, at picnics and other outdoor activities.
They scavenge for meat and sweet liquids, which brings them into frequent contact with humans. Yellowjacket attacks can be deadly for people who are allergic to their stings.
Although many people see their yellow and black markings and label them "bees", yellowjackets are actually a type of wasp. Yellowjackets, paper wasps and bees are differentiated by several physical characteristics.
What makes them dangerous?
Yellowjackets are more aggressive than other stinging insects such as wasps, hornets, mud daubers or bees. Yellowjackets can sting and bite. Since they don't lose their stinger, they can sting numerous times, and will do so unprovoked.
Yellowjackets vigorously defend their nests. Swarm attacks can occur when someone accidentally steps in or hits a nest opening. Ground vibrations can also trigger attacks from underground nests -- thus, mowing lawns can be hazardous during the late summer season when colonies are large.
Most yellowjacket workers forage for food within 1,000 feet of their nest -- a distance of three football fields.
In the middle of the season -- usually June or July -- yellowjackets are drawn to protein sources, such as hamburgers on the barbecue grill. During the late summer to early fall, they tend to shift their diet to sweets, including soda and juice.
Yellowjacket nests are usually built underground, although some species will construct their nests in hollow logs, trees, attics, between walls, or under eaves of houses. An underground yellowjacket nest is difficult to locate because the entrance is about the size of a nickel.
Yellowjacket nests are established by a single queen in the spring. She builds 20-45 cells, lays eggs in them as they are constructed, and forages for nectar and arthropod prey to feed the developing larvae. In about 30 days, the first 5-7 workers emerge and take over the nest-building functions while the queen lays more eggs.
Yellowjackets construct their nests of plant fibers gathered from weathered or decayed wood or even living plants. A yellowjacket nest consists of a number of rounded combs attached one below another. The combs are usually covered with a layered envelope allowing only one opening. A "guard" will usually be stationed at the entrance of a nest to warn of possible danger.
Nest size varies from 300 to 120,000 cells, although the majority of nests average 2000 to 6000 cells and are 3-6 inches in diameter. The largest yellowjacket nests are those of perennial colonies, which do not die out over winter but continue on for additional seasons with multiple queens. These would be most likely found in warmer climates. The nest of one such colony in California was discovered to be nearly 4 feet long, and a nest found in Florida was 9 feet tall. In November 2000, a nest was discovered in a park in Clermont, Florida that measured about 6 feet in height and 8 feet across and weighed 200 pounds. A pest control operator estimated that it contained 25,000 yellowjackets. The record for any yellowjacket nest probably belongs to a nest found in 1960 in New Zealand, which was nearly 15 feet tall, probably contained several million cells in about 1890 combs, and weighed an estimated 1,000 pounds!
The nest decomposes after the season ends and is not reused.
It is important to note that a nest need not be on your property to cause a yellowjacket problem, since yellowjackets can travel up to 1,000 feet (a distance of 3 football fields) from the nest to forage for food.
If you do have a nest on your property, we recommend calling a pest control operator to remove it because of the danger involved.
The onset of spring's warmer temperatures can bring an unwelcome invader: the queen yellowjacket, searching for a spot to settle and start her colony for the summer.
Yellowjacket queens spend the winter in sheltered locations, such as under loose tree bark or in decaying stumps.
During the first warm days of spring, when the daytime temperatures consistently reach the upper 60s to low 70s Fahrenheit, the queen emerges to look for a new site for her nest. The most frequent nest sites are underground, but some yellowjackets have been known to nest in wall voids of a house.
Yellowjacket colonies started by just one queen can grow to include anywhere from 400 to 5,000 workers later in the season.
To prevent some yellowjacket nests from ever being established, you can use the RESCUE!® Yellowjacket Trap to catch the queens in early spring. Every queen caught in the spring means fewer yellowjackets will be around to torment you in the summer.
Catching queens at this time will not decimate the yellowjacket population. But it does decrease the likelihood that yellowjackets will build a nest on or near your property.
Yellowjacket colonies grow exponentially. A colony started by a single queen can produce thousands of workers -- hundreds of which are fertilized at the end of the season and become new queens themselves. The original queen dies, but the new queens overwinter and each produces a new colony the following year.
Yellowjackets are aggressive and can be unpredictable — especially in late summer when their colonies are at their largest. Taking precautions can help you avoid being stung.
- Look before you drink. Yellowjackets are attracted to sweet foods and drinks like sodas and juices.
- Keep trash covered and away from where you may be eating. The insects like to forage in your garbage for food scraps and sweet drinks.
- Wear heavy clothing when walking in wooded areas. Lightweight clothing may not be tough enough to protect you from a sting.
- Remain calm. When you get aggressive, yellowjackets get aggressive.
- If you find a nest, call a pest control professional. Removing one yourself is probably more dangerous than you think.
- Don’t smash or crush a yellowjacket. They give off an alarm pheromone that alerts others in the area to attack.
- Avoid scented perfumes, hairspray, lotions and brightly colored clothes. Yellowjackets are attracted to them.
- Keep your kids away from overgrown or wooded areas. They’re prime nesting sites for yellow jackets.
- Don’t use gasoline to try to eliminate a yellowjacket nest. It’s dangerous and environmentally unsound.
What to do if you’re stung by a yellowjacket:
- Wash the wound with soap and water to remove venom.
- Apply cold water, ice in a wet cloth, or a paste of meat tenderizer and water.
- Take a pain reliever or antihistamine to reduce swelling
- Apply a calamine product to reduce itching.
- Lie down.
- Lower the stung arm or leg below the heart.
- Don’t drink alcohol or take sedatives.
- If the sting is to the throat or mouth, seek medical attention immediately. Swelling can lead to suffocation.
Signs you may be allergic:
- Severe swelling in parts of the body distant from the site of the sting.
- Widespread skin irritation.
- Constriction in the throat and chest or difficulty breathing
- Dizziness or fainting.
If you experience any of these symptoms, seek medical attention immediately.