The brown marmorated stink bug, Halyomorpha halys, aka. Asian stink bug, or shield bug, has given us all a battle, and if not in your area yet, it will be in years to come. Scientists are saying they are still years away from finding safe methods to fend off and/or kill this Asian invader. They do not want to import a known natural predator to kill the stink bugs, the parasitic wasp, because it is not known how the wasp would react once it got here. It may decide it likes a beneficial bug better, and then we would have two pests to deal with. [1] The same is true for chemical treatments, a long-term effect is not known.

The stink bugs stick their straw-like snouts into the produce to suck out the juice leaving a small bit of saliva containing a compound (some say yeast, others say enzyme) that create blemishes on the surface and/or just under the skin. This can cause bruising, discoloration, and a condition known as "catfacing," too, making the produce unmarketable. Commercial growers are losing millions of dollars due to stink bug infestations with no known chemicals or methods to kill or repel the critter.

Homeowners have been inundated with these creatures crawling in groups of hundreds (or more) over their property and into their homes and vehicles, seeking refuge from lowering temperatures, and a warm place to hibernate for the winter. The stink bugs are considered a nuisance pest, costing the owners time and money in attempts to remove them. If homeowners have vegetable gardens or fruit or nut orchards, then there is an additional loss of food for their families.

The following video from the Smithsonian Institutes sums up what is already known about the brown marmorated stink bug and has a few suggestions to keep them out of your house (sealing the cracks and openings).

Entomologist Gary Hevel at the Smithsonian's National Museum of Natural History in Washington, D.C. Here come the stink bugs...

Stink Bug Basics

To catch, destroy, or repel any pest, we must understand what "makes them tick." We need to know exactly what the stink bug can and cannot do. Its survival is based on the same needs as ours: shelter, food, and reproduction. These quick lists summarize the marmorated menace a little better.

Stink bug belly
Image #: 1460049, Pennsylvania Department of Conservation and Natural Resources - Forestry Archive,

Click for larger image.
What A Stink Bug DOES

  • Does suck juice from fruits, vegetables, nuts, and other plants.
  • Does emit a pungent skunk, or dirty foot, type of odor to deter predators.
  • Does generate a pheromone to signal other stinkbugs to its location and/or to mark home.
  • Does fly, and cling to most anything, to travel.
  • Does invade small crevices in tree bark, houses, and vehicles.
  • Does hibernate (or something similar) during winter.

What A Stink Bug DOES NOT Do

  • Does not bite or sting humans or animals.
  • Does not carry or spread diseases.
  • Does not eat other bugs (they do not eat ladybugs).
  • Does not chew or do structural damage to your house or furnishings.
  • Does not eat, mate, or lay eggs while hibernating.
Stink Bug's Lifecycle

We have to know what the pest looks like throughout its lifecycle to take advantage of any opportunity we might have to eradicate them. Here is a chart with descriptions and photos of the stink bugs during various stages of its lifecycle, which can occur during any season since they can have more than one generation per year (depending on the warmth of the climate in your zone).

Eggs There can be 20-30 barrel-shaped eggs lay in a tight cluster underneath a leaf on wild plants. They can be off-white to a pale-yellow, or pale-green color, and approximately 1.6 x 1.3 mm (approx. 1/16 inch).

Image #: 1460049, David R. Lance, USDA APHIS PPQ,

Click for larger image.

Stink Bug Eggs
Nymph-1st Instar Once hatched, this new nymph stays close to the eggs consuming the bacterial food found within the egg remains. It is black with reddish-yellow striped abdomen, red eyes, and about 2.4 mm (approx. 3/32 inch) long.

Image #: 1460052, David R. Lance, USDA APHIS PPQ,

Click for larger image.

1st Stink Bug 1st Instar and eggs
Nymph-2nd Instar After molting, the nymphs change to a blackish color with a tick-like appearance. This photo shows 1st and 2nd instars around the egg mass.

Image #: 1113010, Gary Bernon, USDA APHIS,

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1st and 2nd instar stink bug nymphs and eggs
Nymph-3rd Instar This nymph stage is starting to look more like the adults, growing larger and longer, red eyes, and with the noted white banding forming in the antenna and legs.

Image #: 1460051, David R. Lance, USDA APHIS PPQ,

Click for larger image.

stink bug later instar nymphs
Nymph-4th & 5th Instars The 4th and 5th instar nymphs look very much like the adult stink bug, but have yet to fully develop their wings. They are approximately 12 mm (approx. 1/2 inch) long and have an off-white abdomen with reddish spots.

Image #: 1113015, Gary Bernon, USDA APHIS,

Click for larger image.

possibly a 5th instar Stink Bug
Adult The fully developed adults grow to be about 17 mm (approx. 5/8 inch) long, are a marbled or speckled (marmorated) brown color with distinct dark and white markings around the border of the wings (bottom and sides of "shield"), and have white band segments on the legs and antenna.

Image #: 5018055, Pennsylvania Department of Conservation and Natural Resources - Forestry Archive

Click for larger image.

Adult Stink Bug

Collection Contraptions

Aggravated homeowners, gardeners, and bug-phobic folk, are experimenting with different methods to repel, or lure and eradicate, the stinking little beasties. A few very ingenious, and some just commonsense simple, devices have been designed by clever individuals that seem to work well enough to help decrease the numbers of marmaorated marauders. I have included a few on these contraptions and links for more information below.

Porch Light & Bucket Trap

Porch light & bucket trapMy friend Pam accidentally found a way to collect the stinkers overnight using a bucket hung from a porch light. It seems they were drawn to the light, then stayed for the warm bucket hospitality. All that is left to do is to dispose of the bad bugs using one of the methods below (Know Killers).
Photo courtesy of pdhickey

Cardboard Critter Catcher

Cardboard critter condo trapJody Williams of Delaware Township, NJ, designed a cardboard cubby to collect the brown bugs by propping it against the warm side of his house overnight. He can easily shake the critter condo into a large trash bag with a dose of ammonia water to kill them instantly. The trap is reusable and disposable, but not waterproof. Read more. Dwg. by Bev


Any of these lures could be used together with the traps!
  • The stinkbug's malodorous chemical, or "homing" pheromone
  • Fruits, vegetables, nuts (may draw other insects)
  • Light colors (yellow), bright light, or sun rays
  • Warmth, warm sides of buildings, warm vehicles, etc.
  • South-facing and southwest sides of buildings, especially those reflecting the sun's rays as the day's temperature starts falling.

Stink Bug Death Trap

This is a very simple stink bug disposal method made from a fast food to-go cup. You must gather the bugs from the room with a tissue then place them in the cup. The plans call for using water, but a small amount of dish detergent, alcohol, or ammonia in the water would assure the bugs not crawling back out. Check out the materials and easy construction on Instructables.

A similar design is also being used with a bug lure in the cup, greasing the inside of the cup so they cannot crawl out, and having a couple inches of a killing solution in the bottom of the cup.

Toad, a stink bug predatorKnown Killers:

  • Toads, brown bats, Guinea fowl (and other birds), and the parasitic wasp (from its natural Asian homeland), are all known predators of the brown bug.
  • Low temperatures below 40 degrees may kill them, but freezing temperatures will certainly kill them.
  • Ammonia and solution containing the chemical like window cleaners will kill stink bugs.
  • Alcohol and solutions containing the chemical will kill them.
  • Hairspray; the higher the "hold" level the better and faster it works to kill them.
  • Obviously, fire will kill most anything, including a bug with a built-in shield. Many folks are throwing stink bug "remains" into burn barrels or bonfires to discover they were not dead after all (bugs immediately came flying out). So cover your burn barrels with an old metal window screen or a piece of hardware cloth. When discarding stink bugs from vacuum cleaner canisters or bags, keep the bags sealed, and use heat, cold, or a chemical, to make sure the bugs are dead.
  • There is always water. Stinkbugs can only float or tread water for so long before drowning. To facilitate the extermination process, add a little bit of dish detergent into the water too.

Deterrents & Repellents:

  • Mint leaves, mint extracts, or peppermint oil in particular, has worked for some (will deter ants and mice, too).
  • Try Dawn dish detergent. It kills and/or deters a long list of other pests if a solution of 1-cup detergent to 1 gallon of water, is poured around the foundation of your home BEFORE any bug invasions.

Bye, Bye Brown Bug

I doubt we will see an exodus of stink bugs coming out of our houses this spring, that compares to the invasion there was this fall to enter it. Some stink bugs will not survive the winter, but those that do will replenish the population soon enough. We need to be vigilant with our bug battle by:

  • Recognizing the stink bug eggs and nymphs on the underside of leaves (on mostly weeds) in the spring, April-May in the northern zones and earlier in the south.
  • Keep the weeds cut down and burn the clippings if we need to.
  • Continue to look for the bugs at all phases of their lifecycle throughout the summer on our produce.
  • The Asian stinker can have more than one generation of offspring per season if the weather stays warm long enough.
  • Set homemade lures to collect and destroy them when we can, but try not to inadvertently capture the beneficial bugs with them.

Out of necessity, humans can ultimately be the brown marmorated stink bug's worst enemy! If we start paying more attention and spend a little time to get rid of them, surely the stink bug numbers will not increase, and start declining. Chemicals have already proven of little help in eradicating the bug, while damaging the populations of insects and animals that could actually get rid of the bugs for us (toads and beneficial insects). Do not wait until fall to be reminded that the bug is a menace and needs to be policed all year!


[1] Stinkbug FAQ. Collin R. Marchiando. Rutgers NJAES. Mar 16 2010. Oct 18 2010.