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written by
Marianne C. Ophardt
WSU Extension Faculty
for the Tri-City Herald, Kennewick, WA

The Difference Between Yellowjackets and Paper Wasps

Are yellowjacket and wasps the same pest? No, they’re different and we have both in our area. Paper wasps are a real nuisance in my yard. They’re social wasps (living in groups) and build relatively small open-celled nests (not enclosed with a papery covering.) Our native paper wasps are distinctly different from yellowjackets. They have reddish brown slender bodies with yellowish markings and long dangling legs.

However, our area of Washington has been invaded by the European paper wasp. It has a larger shiny black and yellow body that looks much like the common yellowjackets of the region. Unlike yellowjackets, these invasive paper wasps don’t scavenge for food and are considered beneficial because they eat live insects. They’re often a problem because they build their nests almost anywhere in the yard and will sting if their home is threatened.

The common area yellowjackets build large enclosed papery nests in the ground. The entrance to their nests is small and often unnoticed. During the summer the yellowjackets are helpful by eating live insects. They also forage for other sources of protein, such as dead animals, garbage, and ripe fruit.

Once they secure their dinner, they chew it up and return to their nest to feed it to developing larvae. The larvae in turn produce a nutritious liquid for the adult workers to eat. Yummy! In the fall, the yellowjackets’ insect prey start to disappear plus fewer yellowjacket larvae are available to produce their dinner. Without enough food they turn aggressive when seeking out both protein and sugar based foods. That’s when they become a hazard at outdoor feasts.

How to Trap Yellowjackets

I’ve tried using a bright yellow manufactured trap, as well as a homemade trap baited with sweet syrup and fruit juice, but both didn’t trap any yellowjackets. I have lots of yellowjackets around my yard and I want to get them under control before my big barbecue next week. What am I doing wrong?

The problem may be that you have a problem with paper wasps, not yellowjackets. The good news is that paper wasps don’t forage for protein and sweets at picnics. If they’re causing you a problem near a picnic table, they’re probably defending a nearby nest. Try to locate their open-celled nests and treat with an appropriate aerosol insecticide product labeled for wasp control. To avoid getting stung, follow label directions and apply the spray during the evening when it’s almost dark.

If yellowjackets are a problem, lure traps will work for some types of yellowjackets, but their trapping potential can be enhanced by using meat, such as chicken, as an attractant. The meat should be replaced frequently, along with removing the dead yellowjackets. Place baited traps around the periphery of your yard. If you’re trying to protect a picnic spot in a larger area, place the traps about 200 feet away, spacing them every 150 feet apart.

I have tried the WHY traps you recommended for yellowjacket and paper wasp trapping but they don’t seem to work. How come?

The WHY traps work well for the common yellowjackets and native paper wasps in our region, but their attractant doesn’t appear to be effective for the European paper wasp which now outnumbers the native one. Dr. Peter Landolt, the USDA scientist who developed the attractant for the WHY trap, is trying to develop an attractant that will work for the European paper wasp.

Published: 8/24/2012 2:05 PM


written by

Marianne C. Ophardt

WSU Extension Faculty

for the Tri-City Herald, Kennewick, WA

Two interesting insect phenomenon are bugging area residents. One of these is straight out of a horror movie. Thousands of big black beetles are on the move, marching down streets through yards all going in the same direction. This migration of beetles happens every year, but it’s only noticeable when the population of beetles is high and when the migration occurs suddenly.

The beetles being noticed are darkling beetles. Darkling beetles, also known as stink beetles (more about that later), belong to the genus Eleodus in the Tenebrionidae family of beetles. There are over 1400 species of this beetle family in North America, with most being found in the western part of the continent. They like sandy areas and are very common in desert and coastal regions. About 100 species of Eleodus are indigenous to the western United States, with at least 20 of those species living in our Mid-Columbia region.

As a group, darkling beetles are small to medium sized beetles, ranging in size from 1/16 to 1 3/8 inches in length. Most are black or dull brown. Their antennae tend to be segmented into 11 parts and slightly clubbed on the end. Their wing covers (elytra) are fused and often striated. Because their wings are fused they’re unable to fly, so to get from here to there they must walk. This makes them quite a slow moving beetle.

Darkling beetles are considered beneficial insects because they primarily eat decaying plant matter, such as dead leaves and rotting wood. They only occasionally eat live plant tissues. Most times their presence in yards, gardens, and the desert goes unnoticed, since they are ground dwellers. While active both night and day, they spend the hot part of the day in cool, moist, dark places, such as under rocks and garden debris.

I talked to Dr. Richard Zack, WSU Entomologist in Pullman, about this sudden mass migration being observed in our area. He said that it’s quite common for a number of darkling beetles species to migrate in large numbers in the fall. Some years this movement is more gradual, taking a couple of weeks to a couple of months and it goes by unnoticed. However, Zack notes that this year the abrupt change from hot weather to cooler conditions probably triggered the sudden mass migration being noticed by area residents. He also mentioned that most insect populations increase and decrease in cycles and it sounds like this is a “high” year for darkling beetles in the Mid-Columbia. Zack says if the weather would warm up again it would probably slow down the migration.

Now here is an especially interesting note about the darkling beetles… the reason they’re also known as stink beetles. If they’re disturbed or threatened they will point their rear end up in the air and emit a dark, foul smelling fluid. ( This liquid just kind of oozes out, it doesn’t get sprayed out.) The fluid is stinky enough to ward off potential predators, such as snakes, birds, rodents, raccoons, coyotes, and foxes. This is a particularly effective defense, especially for the large darkling beetle species. If you handle a darkling beetle, you may also encounter this icky, stinky juice, but it should wash off easily.

So while strange and interesting, this mass migration should not cause undue alarm. The beetle migration will soon be over and because they aren’t harmful, no control of their mass numbers is needed. If present in large numbers and causing a nuisance, sweep them up and get rid of them.

Yellowjackets are the other population of insects alarming area residents. While this insect is also considered to be beneficial, it’s a pest when it invades our living areas. They make it difficult to picnic outdoors at this time of year and can be found around garbage cans, car windshields, vineyards, fruit orchards, and anywhere else they can pick up a meal.

Why are there so many of them? In late summer and early fall, yellowjacket colonies are close to the end of the season and their workers are out looking for food for their queens. The queens are very important because they are the only yellowjackets that survive the winter. The rest of the colony dies. As summer draws to an end, their main source of food… other insects… becomes less available. This forces yellowjacket workers to find other sources of food. Plus, at this time of year their populations are at their highest, making competition for food fierce. The yellow jackets become very assertive and aggressive in gathering food. In the fall, they’re particularly fond of sweets, including soft drinks, fruit, and ice cream.

Sanitation and avoidance are your best options in dealing with a yellowjacket problem at this time of year. If dining outdoors, keep food and drinks covered until you’re ready to eat. Clean up any spills and put away leftovers as soon as you finish eating. If possible, dispose of your trash within closed plastic liners in trash cans with tight fitting lids. If there are leaks, be sure to clean your trash can. Remove and dispose of fallen and unwanted fruit from apple, plum, pear, and other types of fruit trees, as well as from grape vines. In parks, locate your activities as far away as possible from trash cans and dumpsters.

If you encounter yellowjackets outdoors, try to avoid a confrontation. Move carefully away, don’t automatically swat at them. Stay away from the fly swatter when involved in yellowjacket confrontations. Threatened yellowjackets give off an insect scent that warns other yellowjackets of the attack and summons them forth to provide assistance. Also, be aware that perfumes, hair products, and brightly colored clothing can attract yellowjackets. Check your open soft drink can before drinking… they will sometimes find their way inside when you’re not looking. This type of encounter is particularly dangerous.

Commerical yellowjacket lure traps are available at home and garden stores, but these traps provide little benefit at this time of year when yellowjacket populations are so high and will soon disappear with cold weather. However, if you decide to give them a try, locate them at the outer edges of the area you want to protect… to draw them away from where you will be eating or playing. Follow the label directions for the particular trap you purchase. If they call for a bait, some good ones include canned cat food, tuna, liverwurst, jelly, and fruit juice.

So what’s bugging you now?

Published: 9/18/2004 2:16 PM


written by

Marianne C. Ophardt

WSU Extension Faculty

for the Tri-City Herald, Kennewick, WA

Trying to have a relaxing picnic in your backyard, a campground, or a park at this time of year can be downright dangerous because of the large yellow jacket populations foraging for food. I was at a backyard picnic last week where yellow jackets destroyed any thought of having a relaxing lunch outdoors. Everyone was worried about getting stung by these aggressive creatures. They particularly seemed to like the fried chicken. (I can’t blame them, it was good chicken.)

Many of the folks at the picnic were calling these obnoxious creatures “bees.” They weren’t bees. Honey bees are hairy little yellow-gold to yellow-brown creatures that subsist exclusively on flower nectar and pollen. They’re not considered an aggressive insect, but they will defend themselves or their colony if threatened. Most bee stings occur accidentally, such as when you put your hand or bare foot on top of one. This fight to defend themselves is a “fight to the death” because honeybee stingers are barbed. When they sting, their stinger is left behind in your skin and the bee dies.

Yellow jackets are a type of wasp and quite different from bees other than they can both sting humans. The most common yellow jacket in our area is the western yellow jacket. It’s part of a ground-nesting family of yellow jackets. The western yellow jacket is hairless and colored black with bright yellow band markings. The western yellow jacket is sometimes called the “meat bee” (It’s not a bee!) because it feeds on meat. As a rule, wasps feed primarily on other insects or other animal protein food sources with some exceptions. Yellow-jacket stingers are not barbed, enabling them to sting repeatedly without harm to themselves.

Western yellow jackets are a problem almost every year during the late summer and early fall. There’s several reasons for this. First, their population has been increasing in numbers since one overwintering queen founded the nest by laying eggs early in the spring. One nest started by one queen may have as many as 5,000 workers by the end of summer. These workers are the ones foraging for food.

If their large numbers weren’t enough to make them a nuisance, their increasing aggressiveness makes them obnoxious and potentially dangerous. They become so aggressive because they’re hungry. As their nest was growing, the job of the workers was to forage for protein and feed it to the larvae. In return the larvae secreted a sugary material that the workers ate. In late summer the production of new larvae ceases and this multitude of workers crave their “sugar fix” but aren’t able to get it because of the dwindling number of larvae. As a result, they become quite bold and belligerent in finding alternate sugary foods… and picnics are a surefire banquet for them, especially ripe fruit, soft drinks, and other sweet stuff.

Fall is here and multitudes of yellow jackets are here too. How can we control them now? Quite simply we can’t. There are some actions that we can take to protect ourselves from them, but control is pretty much out of the question at this time of year unless you can locate their nests. My first word of advice is don’t swat at them… like everyone at the picnic I attended was doing. This can incite them to protect themselves by stinging you. You do best to stay calm and unmoving, and then after a bit move slowly away. (I realize that this is almost impossible advice to follow!)

To minimize the attraction of yellow jackets to your picnic, leave food, especially fruit and sugary drinks, covered until the group is ready to eat. Throw leftover picnic fare into well sealed trash cans. In park or fair situations, dumpsters should be cleaned daily at this time of year to reduce the food they provide for foraging yellow jackets. Be aware that after you’re done eating and all the food is stored away, the yellow jackets will stay in the area and continue to look for those tasty goodies that attracted them to the area.

If you grow fruit in your garden, remove and dispose of fruit when it ripens… if you don’t plan on eating it. Yellow jackets seem to especially like ripe grapes in both home and commercial vineyards in the fall.

There are also special lure traps available for yellow jackets. They are most effective when used in the spring when the overwintering queens first emerge and before they start building nests. The more traps set up to catch those queens, the greater chance of reducing worker populations at the end of summer. The lure traps are not very effective in reducing large worker populations at this time of year, so be sure to start early in the spring. Follow label directions regarding how to use them effectively and how often you need to renew the chemical attractant.

When not attacking us at picnics or in our gardens, yellow jackets are considered beneficial insect predators eating a variety of caterpillars, flies, and grubs.

Published: 9/8/2007 2:36 PM



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