- What Are Stink Bugs?
- Brown Marmorated Stink Bug
- Life Cycle and Biology
- Household Invader Prevention and Control
- How to Get Rid of Stink Bugs in Your Home
- How to Get Rid of Stink Bugs
- Getting Rid of Stink Bugs
- Natural Stink Bug Control
- Professional Stink Bug Treatment
- Small grey bugs hanging on your walls or ceiling? How to get rid of Bagworms & Casebearers
- What are they?
- Why are they in my house?
- What can be done about them?
- Life Stages
- Stink Bug Nymphs in Corn
- Green stink bug description
- Life cycle and biology
- How to get rid of the green stink bug physically
- Green stink bug prevention
- “Keep a green tree in your heart and perhaps a singing bird will come.”
- Aphids- Leaves sticky from small green bugs
What Are Stink Bugs?
Pentatomoidea, commonly known as stink bugs or shield bugs, is referred to a super family of insects belonging to the Heteroptera suborder. In this suborder, the insects share common characteristics such as piercing mouthparts as well as a particular kind of wings, which are toughened at the base and membranous at the tips.
The scientific name of stink bugs, Pentatomoidea, has been derived from the fact that they have an antenna which is divided into five segments. Stink bugs have broad bodies that are either in triangular or semi-elliptical shape. Their bodies serve the purpose of defensive shield against predators; this is why they are sometimes referred to as “shield bugs”.
Stink bugs excrete offensive smelling liquid from their thorax glands that are placed in between the first and second pair of legs. When they are molested or attacked by predators, they produce this liquid defensively in order to put off potential threat to their lives. Usually, they are not considered to be pests for they do not render significant loss to plants; however, when they make a larger group, they may become considerable pests.
It is worth mentioning here that all stink bugs have sucking mouthparts and broad bodies, but still there are variations in their body colorings. On account of this distinction they are further divided into fifteen different species. Among them brown stink bugs and green stink bugs are the most famous types.
Brown Stink Bugs
The Brown Marmorated Stink Bugs, scientifically known as Halyomorpha halys, are insects in Pentatomoidea family found in Asian counties like China and Japan. The size of adult brown stink bugs varies from individual to individual ranging from 1.5 cm long to 2 cm. When they are nymphs, they are red in color that becomes black and ultimately brown as soon as they become adults. Although their underside remains white even after reaching adulthood, it is their brown legs with faint white banding that make them distinct from other similar bugs.
The brown marmorated stink bugs are regarded as agricultural pests for they render widespread harm to fruits and vegetable crops. Their major hosts include maple, birch, serviceberry, catalpa, butterfly bush, pecan, redbud, hackberry, pepper, dogwood, citrus, cucumber, tomato, sunflower, apple, pear, plum, and grape. Brown stink bugs use their proboscis to suck the host plants and resultantly they not only create necrotic areas on the surface of fruits but also even cause seed loss and transfer of plant pathogens.
Another distinct characteristic of brown bugs is that they go into the state of hibernation in winter seasons and invade homes or structures where temperature does not fall critically. Their hideouts include under siding, windows and door frames. However, in spring they remain active in feeding on plants and vegetables.
Green Stink Bugs
The green stink bugs, scientifically known as Acrosternum hilare, are the species of stink bugs that belong to Pentatomoidea family. Since it originates from Asian countries particularly Japan and China, they are also called as “Asian Stink Bugs”. It is similar to Brown Marmorated Stink Bug in terms of certain characteristics like stink glands, broad bodies and sucking trait. Both green and brown stink bugs are pest species targeting mostly the southern parts of the USA.
However, the difference between green and brown stink bugs is the color variation. As the name itself implies, the green stink bug has bright green color. Their adult bugs have also an orange line that separates their heads from bodies. On the other hand, the nymphs are generally black in color with underdeveloped wings; on reaching adulthood, they also turn green and get defensive shield on their broad bodies.
As far as their host plants are concerned, these include mainly orange trees, cherry trees, soybean, and apple trees. They cause significant damage to gardens and farms for they mostly remain unnoticed by the farmers on account of their green color. Furthermore, they use green plant not only as a food but also as a safe haven during their breeding period. Here they lay eggs on host plants in an excessive number and increase their race.
Brown Marmorated Stink Bug
The brown marmorated stink bug (BMSB), Halyomorpha halys, is an introduced, invasive insect new to North America. It was first identified in fall 2001 in Allentown, PA; though unconfirmed reports go back as far as 1996. The accidental introduction was possibly via shipping containers from Asia. It is native to China, Japan, Korea and Taiwan.
BMSB is a plant pest that uses its piercing-sucking mouthparts to feed on sap from a wide variety of plants, including field crops, vegetables, fruits, trees and shrubs. In addition, like the boxelder bug and the multicolored Asian lady beetle, BMSB congregate on houses and buildings in the fall of the year and accidentally wander inside as a nuisance pest. Stink bugs are named for the characteristic, disagreeable, odor they produce, and the cilantro-like odor from BMSB makes the invasion even more distressing.
BMSB has been found in 43 states. The first discovery in Iowa was in Cedar Rapids in 2011. Currently, it has been reported in 33 Iowa counties. Please report additional county-detections to [email protected] BMSB has caused crop damage in the mid-Atlantic region and minor agricultural problems elsewhere. In Iowa and the remaining states where detected it has been reported primarily as a household nuisance.
BMSB was the subject of an article in the The New Yorker magazine on March 12, 2018.
Brown marmorated stink bug. Note the
banded antennae and the alternating light and
dark areas on top of abdomen. Photo by D.
Shetlar, Ohio State University Extension
BMSB is similar to other stink bugs with a roughly-triangular or “shield” shaped body. The adults are approximately 5/8 inch long and mottled brownish-grey in color. The word “marmorated” means marbled, a description of the mottled color on the back of BMSB. BMSB can be distinguished from other species of stink bugs by the alternating dark and light bands on the last two segments of the antennae, and the alternating light and dark banding on the exposed upper edges of the abdomen. The underside of the abdomen is light-colored.
Compare BMSB to other stink bugs and “look-alikes” common in Iowa at Stink Bugs and Similar-Appearing Insects.
Life Cycle and Biology
BMSB spends the winter in the adult stage hiding in houses and other protected locations. In May the adults leave the hiding sites to feed on sap from plants. After mating, the females lay eggs in clusters of about 28 eggs on the undersides of leaves from June to August. A single female can lay up to 400 eggs. Eggs hatch into wingless immature bugs called nymphs that feed and grow for about 5 weeks before reaching the adult stage in late summer. There is one generation per year.
To date, damage to field crops, fruits, vegetables or ornamentals has not been reported in Iowa. Damage in Iowa and nearby areas has been limited to the annoyance and nuisance of stink bugs entering homes, office buildings, etc.
Underside of brown marmorated stink bug.
Note the light color. Photo by D. Shetlar, Ohio
State University Extension Entomology.
BMSB enters buildings in the fall when they are seeking sheltered locations where they can successfully spend the winter in hibernation. They are not seeking warmth and they cannot predict colder temperatures nor that a house will be heated during winter. Like ladybugs, boxelder bugs and cluster flies, every stink bug found indoors walked or crawled in through cracks and gaps during the fall of the year (usually late September to October). Typical entry points include cracks and gaps around windows and doors, between the foundation and siding, between the siding and soffit, around chimneys and so forth.
Stink bugs do not bite, they cannot sting and they do not feed on structures or house contents or occupants. They are a nuisance and annoyance to residents because they are large, can occur in large numbers and fly. They cannot cause any structural or cosmetic damage to your home. Further, stink bugs (and boxelder bugs, ladybugs and cluster flies) cannot reproduce indoors or during the winter. While inside, BMSB do not feed and they do not reproduce. In fact, females are incapable of reproducing until early spring.
Household Invader Prevention and Control
The first step in household accidental invader management is to seal cracks, gaps and potential entry points before they get in. Exclude BMSB by sealing cracks and openings with caulk or weather-stripping. Keep windows, screens and doors in good repair so they seal tightly.
Stink bugs already indoors should be removed vacuumed or swept up and discarded. If you use a vacuum cleaner or shop vacuum the vacuum bag should be promptly removed and discarded. Indoor insecticide sprays for BMSB are not recommended. Spraying indoors, including the use of “bug bombs” does not prevent entry and only accidental invaders out in the open at the time of treatment will be affected.
Do you live in Iowa and have an insect you would like identified?
The Iowa State University Plant & Insect Diagnostic Clinic will identify your insect, provide information on what it eats, life cycle, and if it is a pest the best ways to manage them. Please see our website for instructions on mailing insects and digital images.
Contact information for each states diagnostic laboratory for U.S. residents. If you live outside of Iowa please do not submit a sample without contacting the Plant & Insect Diagnostic Clinic.
How to Get Rid of Stink Bugs in Your Home
Many species of stink bugs live throughout the Unite States. Recently, a new type of the pest, the Marmorated stink bug, is making North America its home.
Step 1 – The Marmorated Stink Bug
The Marmorated stink bug most likely hitchhiked its way into the United States from China. It was first found in Allentown, Pennsylvania in 1998. Stink bugs enjoy hanging out in the garden eating almost any kind of fruit or vegetable which it pierces with a proboscis that protrudes from its mouth. In the fall, stink bugs start looking for a warm shelter. They begin to make their way into our homes in September through October. The insects are called stink bugs because they are equipped with glands that emit a noxious smell when they feel threatened.
Step 2 – Identifying the Marmorted Stink Bug
The uninvited Marmorted stink bug looks like a walking shield with its triangular shaped, brown body. Stink bugs are drawn to the outside of our homes because of the warmth on cool fall nights and lights that are left on at night. It is not uncommon to find a multitude of stink bugs attached to window screens and fluttering around porch lights.
Step 3 – The Life Cycle of Stink Bugs
Stink bugs have a mating season that spans from June until August. The female stink bug lays bunches of 20 to 30 eggs on the underside of leaves. Adult sink bugs can live several years and hibernate in the winter. They use our homes as a winter retreat not for reproducing. The bad news is that they leave a scent inviting other stink bugs to join them.
Step 4 – Stopping a Stink Bug Invasion
The best defense against a stink bug invasion is to prevent them from gaining access to your home. Check your home for any holes or cracks where they can enter. Pay special attention to areas around windows, doors, pipes, utility wires, chimneys, attics, basements and garages. Remove air conditioning units at the end of the summer to take away a favorite stink bug hangout. Maintain screens to make sure there are no rips and that they fit tightly. Call a professional exterminator to spray insecticide around the perimeter of your house; however, this is a temporary method due to it degrading quickly. It is not a good idea to release bug bombs or powders to get rid of stink bugs, because if the pests are killed in hard to reach places their decaying bodies can attract scavengers like the carpet beetle.
Step 5 – How to Get Rid of Stink Bugs in Your Home
Unfortunately, stink bugs are a big problem in the Mid-Atlantic States so you may find them in your home. Smacking a stink bug with your shoe is not a good idea, since it will release a foul smell that can linger for more than six months. When you discover a stink bug you want to remove it intact. The best thing to do is to scoop it up into a disposable cup and let it go outside. For a more persistent problem, use a vacuum cleaner with a bag to suck up the stink bugs. Discard them in an outside trash container.
How to Get Rid of Stink Bugs
Stink Bugs are equipped with specialized glands on their underside capable of producing a foul odor, emitted through tiny slits. They belong to the order Hempitera, which means half wing. That’s because the back half of the stink bugs forewings are composed of a translucent membranous material. The hind wings or pair closest to the back is entirely translucent. They are generally categorized into 2 subspecies, the Green Stink Bug (also known as the green soldier bug) and the brown stink bug (marmorated stink bug). Both are found all over the United States, the brown stink bug proving to be far more of a nuisance. Others refer to stink bugs as shield bugs, their body shape resembling the shape of a shield, extending approximately ¾ inches in size. Brown stink bugs are capable of flight and sightings are most prominent in the transition from summer to winter (between September and December), especially in the north around Pennsylvania, Maryland, New Jersey, and neighboring states.
- Jump to:
- Getting Rid of Stink Bugs
- Natural Stink Bug Control
- Professional Stink Bug Treatment
Getting Rid of Stink Bugs
Brown stink bugs release a foul odor when threatened that smells like rotting garbage and pine. This odor is also used to attract potential mates. They feed on plant juices and are notable in agricultural areas for the damage they inflict on crops. Some species even feed on beetles and caterpillars. They are also known as an overwintering pest, readily entering structures when temperatures dip too low. They lay eggs in piles of leaves, heaps of garbage, or the underside of plants. The eggs are often compared to the cells of a honeycomb or tiny spined barrels. Brown stink bugs often go unseen due their ability to blend in with their surroundings, appearing the same colors as the leaves and tree bark upon which they rest. Most species have relatively long antennae.
Natural Stink Bug Control
Any product containing the active ingredient Carbaryl should be sufficient for use on plants. It is made from a specialized ingredient found naturally in tree sap and very effective. It can be found at most home appliance stores and recommended if a homeowner is faced with spraying edible plants. Damage to plants will appear as a diamond shaped or circular holes in the leaves. The areas immediately surrounding these holes will brown in color as they dehydrate. If the stink bugs are left untreated, they will exhaust the plants resources until it dies. Plants are often able to revive themselves, but extra attention and water is recommended following a swarm of brown stink bugs. Use the appropriate plant food may also be necessary to rehabilitate the plants back to standard health. Any weeds in the lawn should be pulled and displaced, as they are capable of housing many tiny yellow eggs.
Professional Stink Bug Treatment
On occasion, a homeowner may find many brown stink bugs inside the home. This is more common as temperatures drop below 70 degrees around autumn. It’s preferable to vacuum them up with a hose attachment or spray them with a non-staining insecticide then it is to crush them, due to the malodorous glands on the bottom of their abdomen. Stinkbugs that are higher up can be swept off the ceiling using a broom so as they are not crushed. Be prepared as they will release a tiny amount of odor, but it won’t last very long. Also be sure to check around windows and curtains indoors. Insecticides labeled for exterior use can be used around doors and windows to limit points of entry. Brown marmorated stink bugs are attracted to light, so ensuring treatment around light fixtures is also recommended. Suspend SC, a safe commercial pesticide, has also been shown to be very effective when applied around points of entry. As always, exclusion is the best practice when it comes to a bug free home. Make sure all windows are properly screened and sealed, including any doors. The room that you have the most in is likely the point of entry – once inside, they will not be able to survive. The nutrients their bodies require are in the plants around your home and within a week’s time they will disappear on their own. In the absence of insecticides, many homeowners will spray a combination of soap and water around windows and door frames. Washing the side of the home using soap and spray attachments has also been reported as an effective means of their control, as they are often reported in high numbers, resting on the sunnier side of the house for warmth.
Small grey bugs hanging on your walls or ceiling? How to get rid of Bagworms & Casebearers
What are they?
Have you noticed small greyish to white colored bugs hanging on your walls or ceiling? Or maybe it looks like some kind of egg sac? What you are likely seeing is a cocoon-like case, with an insect hidden inside. The common name for these creatures is a Plaster Bagworm, however, it is more etymologically accurate to refer to them as Household Case Bearers (Phereoeca uterella). Dust Worms are another common name for these creatures. The long oval-shaped little case or “bag” that is most commonly found in homes and garages are the cocoon created by the larval or caterpillar stage of a moth.
Despite ultimately transforming into a moth, it is not typical to have significant numbers of moths visibly flying about the house. If this is the case, it is more likely you may have an infestation of Indian Meal Moths.
Why are they in my house?
Like people, insects have basic needs such as food and shelter, that must be met in order to survive. For Plaster Bagworms and Household Casebearer, those needs are VERY basic. Their diet consists of old spider webs, dead insects, and even human hair. Part of the reason these insects are found stuck to walls and ceilings is that they have climbed up there to be closer to the cobwebs they feed on. It doesn’t take much to satisfy a hungry Plaster Bagworm.
Household Casebearers and Plaster Bagworms are common throughout the Southeastern United States. Thriving in warm and humid climates, they are a particular nuisance in Florida where their population in and around homes can become quite high if some mitigating measures aren’t taken.
It’s very common to find Plaster Bagworms and Household Casebearers attached to the exterior stucco, vinyl or wood siding of homes as well.
Bagworms and Casebearers will eat wool, but they will not eat cotton or nylon.
What can be done about them?
Because both their diet and the material used to create their cocoon is basically tiny bits of organic material, thorough and consistent cleaning can remove both the food and shelter they need to survive and result in a decreased population. This, however, can be a bit difficult in areas such as garages, carports, patio, and lanai areas. Nevertheless, sweeping down cobwebs, and blowing out accumulated debris in garages and porches will help prevent a thriving Casebearer population.
Reduce Outside Lighting
Another good tip for preventing Plaster Bagworms is to reduce outside lighting. Ultimately, these little creatures are moths. Moths are notoriously attracted to porch lights. If moths are attached by a light left on in the garage, or a security light on the side of the house, you are attracting them to your home. It is ultimately these adult female moths that will lay the eggs that eventually turn into the annoying little egg sac-like creature stuck to your ceiling.
Keep Temps & Humidity Moderate
Obviously, there is little that can be done in this regard in outside areas. There is a reason, though, that they have the name HOUSEHOLD Casebearer. They are certainly capable of surviving inside homes. Another reason why you’ll find these weird little bugs in these areas is that they, like all insects, prefer warmth and humidity. Plaster Bagworm populations will be higher in homes where the inside temperature is kept above 80 degrees. If, like many Floridians, your home is only occupied part of the year, be sure to keep your A/C running even when you are away.
Often homeowners will sweep down the caterpillar cases along with any cobwebs nearby. While this can be somewhat helpful, it is limited in its effectiveness in two way.
1) The moth’s larvae are well protected inside their cocoon.
2) The material they consume, spiderwebs and the remains of dead insects caught in them, simply end up on the floor, still easily available for the Plaster Bagworm to eat.
By vacuuming, whether, with a household vacuum or a shop-vac, both the bagworm itself and the material it eats are effectively removed from the premises. Remember to empty the contents of the vacuum into a garbage bag and take the bag out of the house, or you may just end up with a bunch of well-fed moths living in your vacuum.
What are they?
The brown marmorated stink bug (BMSB) is a 0.5- by 0.625-inch shield-shaped insect that uses its piercing mouthparts to suck plant juices from fruits, seed pods and nuts on a wide variety of wild and cultivated plants. It was accidentally brought to North America from Asia sometime before 1996 and was first detected in Michigan in 2010. Also known by its scientific name, Halyomorpha halys, both BMSB adults and nymphs – the immature stages of the bug – feed on a number of important fruit, vegetable and ornamental crops. Where it has been established for some time, it is now a major pest for growers of susceptible crops. As of September 2017, it has been found in 61 Michigan counties and is well established in the southern part of the Lower Peninsula.
For HOME or STRUCTURAL concerns
What are they doing in my home?
At the end of the summer and into the fall, you may start to find brown marmorated stink bugs appearing in homes and other buildings. They are looking for a protected place to spend the winter. They will leave your house again in the spring – if they can find their way back out – to look for plants to feed on and lay their eggs outside.
They are NOT nesting, laying eggs or feeding on anything or anyone in your house. These are plant-feeding insects with straw-like mouthparts for drinking plant juices – they are harmless to humans and pets.
What can I do about it?
- Try not to panic.
- Look for gaps around window air conditioners or holes in window screens and block them off – these are easy access points for brown marmorated stink bugs to enter homes.
- The easiest, non-toxic way to dispose of them is with a couple inches of soapy water in a bucket – the soap prevents them from escaping the water. Sweep them into the bucket and they will drown in the soapy water, which you can then dump outside. Or you can do the same with a Shop-Vac – add the soapy water to the canister before vacuuming them up with the Shop-Vac.
- If you want to help MSU Extension track where BMSB are appearing in the Michigan, you can report how many you’ve seen at a given location using the Midwest Invasive Species Information Network (MISIN). If you have trouble entering the information on the Midwest Invasive Species Information Network website, email Julianna Wilson at [email protected] with your name, address (or nearest crossroads), the date you saw them, and how many you have seen.
View larger image. As of December 2017, more than 12,000 reports have been submitted to MISIN from all but five Michigan counties. From these reports, we know BMSB is well-established in counties colored in red (darkest color), and we do not need any more reports if you see BMSB in these areas. Outside of the counties in red, we are interested in hearing where BMSB is being found. Reports should be submitted through the MISIN website.
For more tips on managing them in your home, see our tip sheet on stink bug identification and management in homes or read this article, “Managing brown marmorated stink bugs in homes.”
For more information on why and how to report sightings of BMSB in your home, see “Why and how to report sightings of brown marmorated stink bugs in your home or business.” If you have already reported a sighting from a particular address, you do not need to report from that address again.
For GROWER concerns
What crops are affected?
Brown marmorated stink bug can feed on more than 300 different plants including many agricultural and ornamental crops – almost anything that produces fruit, pods, or nuts. Feeding damage has been recorded in high-value specialty crops, in particular apples, pears, peaches and other stone fruit, fruiting vegetables such as tomatoes, sweet peppers, squash, pumpkins, sweet corn, and green beans, and field crops such as soybeans. They can also become a contaminant during juice or winemaking in grapes. For more information on susceptible crops, visit the Stop BMSB website.
How do I monitor and manage them in my crop?
Brown marmorated stink bugs move around during the season among different habitats, coming out of woodlots and manmade structures in the spring to find host plants. There are exotic tree species common in Michigan woodlands and especially in more urban areas that are favored in the early season, especially Tree of Heaven. Later they will move into crop habitats, especially soybean fields, vineyards, and orchards. Their movement appears to coincide with the development and maturity of seed pods and fruit in these crops.
In general, you are most likely to find the pest in the edges of a crop planting. Sweep netting will work in field crops to monitor for the pest. In orchards and vineyards, beating limbs or vines over trays can help determine whether they are present. There are also commercial lures that can be paired with various traps to attract them for recording their number from week to week. Traps are best used between two habitats, like between a woodland and the crop of concern. Thresholds are still being developed in many crops that use these traps.
For more information about damage assessment and management strategies in fruit:
- Michigan Fruit Management Guide, MSU Extension bulletin E0154
- Managing Brown Marmorated Stink Bug in Michigan Orchards by MSU (updated July 2018)
- Look-a-like late season apple damage by bitter pit, brown marmorated stink bugs or apple maggot by MSU
- Integrated Pest Management for Brown Marmorated Stink Bug in Vineyards by Stop BMSB
- Integrated Pest Management for Brown Marmorated Stink Bug in Small Fruit by Stop BMSB
For more information about management in vegetable crops:
- Midwest Vegetable Production Guide for Commercial Growers, MSU Extension bulletin E0312
- Integrated Pest Management for Brown Marmorated Stink Bug in Vegetables by Stop BMSB
2019 trap line reports
MSU Extension runs a trap line in the major fruit and vegetable growing regions in the Lower Peninsula of Michigan, monitoring between 60-80 sites each week during the season. Periodic reports are posted with results from these trap lines and are meant to assist growers with knowing where BMSB populations are increasing in a given region.
- Sept. 13 BMSB report – Fruit and vegetable being monitored for brown marmorated stink bugs in southern Michigan have a significant increase in numbers this week. Include this pest in your management plan in susceptible crops.
What to do if you are not sure whether you have a BMSB?
Place it in a dry box with tissue paper or in white vinegar and mail or drop off to:
578 Wilson Rd., Room 116
East Lansing, MI 48824
Be sure to include with the specimen the location where you found the insect and your name and contact information (email or phone if no email). See additional tips for submitting insects for identification to MSU Diagnostic Services.
- NEW: Managing Brown Marmorated Stink Bug in Michigan Orchards (updated July 2018), tip sheet by MSU Entomology
- Brown Marmorated Stink Bug (BMSB): Information for Michigan Residents, tip sheet by MSU’s Paul Both and Diane Brown
- Brown marmorated stink bug moves into the Midwest, tip sheet by MSU‘s Christina DiFonzo and Howard Russell
- Stink Bug Basics from Stop BMSB
- Brown Marmorated Stink Bug Regional Pest Alert by NC IPM Center
- Past articles from MSU Extension’s Fruit & Nut News and Vegetable News
Brown marmorated stink bug (BMSB) overwinters as adults in a protective sleeplike state, emerges in the spring, and begins mating in about two weeks. BMSB commonly mates multiple times, and the female may deposit as many as 486 eggs in a lifetime. Development from egg to adult requires approximately 538 degree days, a measure of temperature and time for insect growth, with an additional 148 degree day period before eggs are laid. Its light-green eggs are often laid on the underside of leaves, deposited in masses of approximately 28 eggs.
From left to right, four nymphal stages of BMSB (second through fifth instar), adult male, and adult female. Photo by W. Hershberger
BMSB nymphs, first instar, cluster around a mass of newly-hatched eggs on the underside of a leaf. Photo by W. Hershberger
Adult BMSB on an apple. Photo by W. Hershberger
While the adults blend in with tree bark, the nymphs are more brightly colored. BMSB has five nymphal stages ranging from 2.4 mm to 12 mm in length. Early-stage nymphs do not venture very far from the newly hatched egg mass. The legs and antennae of nymphs are black with white banding. Early-stage nymphs have dark reddish eyes and a yellow-reddish underbelly with black stripes.
BMSB may be able to produce several broods in a single year, thus increasing the potential and duration of risk for crop damage. Our research team is seeking to understand the unusual overwintering behavior of the stink bug, as it is believed to move readily among woodlands, buildings, and farmland.
H. Kawada and C. Kitamura, 1983, “The reproductive behavior of the brown marmorated stink bug, Halyomorpha mista Uhler (Heteroptera: Pentatomidae). I. Observation of mating behavior and multiple copulation.” Applied Entomology and Zoology 18: 234-242, via Tracy Leskey et al, 2011, “Biology, ecology, and management of brown marmorated stink bug in orchard crops, small fruit, grapes, vegetables, and ornamentals: USDA-NIFA SCRI coordinated agricultural project.” USDA-ARS Appalachian Fruit Research Station. For more information about the SCRI project proposal, contact project director Tracy Leskey.
University of California at Davis IPM Online provides an excellent introduction to the degree day concept.
“How to Identify Brown Marmorated Stink Bug.” Rutgers New Jersey Agricultural Experiment Station, accessed April 24, 2012.
K. Kiritani, 2006, “Predicting impacts of global warming on population dynamics and distribution of arthropods in Japan.” Population Ecology 48: 5-12 via Leskey et al. 2011.
K. Kiritani, 2007, “The impact of global warming and land-use change on the pest status of rice and fruit bugs (Heteroptera) in Japan.” Global Change Biology 13: 1586-1595 via Leskey et al. 2011.
Leskey et al. 2011.
Euchistus servus (brown stink bug); Euchistus variolarius (one-spotted stink bug); Acrosternum hilare (green stink bug)
Stink bugs feed on tomato fruit. The piercing-sucking mouthparts of the adults and nymphs cause cloudy yellow blotches just below the skin of the fruit.
Some stink bugs feed on insect pests. You can distinguish the plant feeding (pest) stink bugs from the predatory (beneficial) stink bugs by the proboscis (beak). Predatory stink bugs have a wide proboscis for attacking other insects, while plant-feeding stink bugs have a narrow, needle-like proboscis for probing plants.
Often Confused With
Tarnished plant bug
Stink bugs overwinter as adults and have 1- 2 generations per year, depending on species.
Period of Activity
Adults are active at temperature above 21°C (70°F). The time for concern is July through to harvest. Stink bugs may move into tomato fields when surrounding vegetation dries up or after nearby cereal or forage harvest.
Inspect the fruit for damage. Search for the pest (adult and nymphs) in the lower parts of the plant and on the soil under the plant. Shake the foliage onto a tray or sheet. Damage often occurs along field edges.
- Stink bug damage is not a concern for processing tomatoes destined for paste.
Stink Bug Nymphs in Corn
Eileen Cullen, Extension Entomologist
Stink bugs are making an appearance in cornfields, particularly the green stink bug. Both the green stink bug, Acrosternum hilare, and brown stink bugs, Euschistus spp. can be found in corn and soybean fields during August.
Green stink bug nymphs are commonly taken for some type of beetle with concerns of silk or kernel feeding. However, this is not a concern. Stink bugs are a true bug, not a beetle. They have piercing-sucking mouthparts and cannot chew husks, kernels, silks or leaves.
Green stink bug nymphs and adults have been reported this week from corn fields in Lincoln and Marathon counties in north central Wisconsin, and the Pierce and St. Croix County area (near Spring Valley) in western Wisconsin. You have likely observed them in other locations, or other crops such as grapes.
Green stink bug nymphs on corn.
Photo: Isaac Nellessen
Nymphs of the green stink bug are easy to distinguish from other species by black bands on the abdomen and orange markings near the head.
Stink bugs are unlikely to cause economic damage to corn and soybeans in the Upper Midwest. There are no damage relationships or economic injury level established for stink bug on field, seed or processing sweet corn at this stage in the season. On soybeans, the green stink bug is a key pest (feeding on pods and seeds) and economic problem in the southern United States, but rarely in the northern states. Scouting and threshold information are provided below for soybeans.
Feeding Behavior and Field Distribution
- Stink bug nymphs and adults feed with piercing-sucking mouthparts. They seek out seed pods, fruits, grain heads, inserting their needle-like mouthpart, injecting enzymes to dissolve plant tissue, then sucking out “pre-digested” plant fluids.
- Stink bugs cannot clip silks in corn (do not have chewing mouthparts).
- Edges/sides of fields adjacent to wooded habitat are likely spots to find stink bugs, rather than throughout the field or in the middle of the field. (During early summer, stink bugs feed on berries, pods, seed heads in uncultivated, wooded areas).
- Males emit a pheromone which signals to other members of the same stink bug species a call to “clump” together (suitable food, mates, habitat).
- Stink bugs aggregate, and it is more common to find them on field edges and in groups on plants or spots in field sides/edges – rather than distributed throughout a field, or in the middle of fields.
- Stink bugs emit a strong odor as a defense mechanism.
- Stink bugs overwinter as adults under protected areas like leaf litter, wooded areas, river edge vegetation.
- In the Upper Midwest, stink bugs are thought to migrate northward from overwintering sites in their adult stage. There is usually one generation per year in this region.
- Stink bug adults have a shield shaped body, with pointed “shoulders”.
- Green stink bug adults are bright green with black bands on their antennae. Nymphs are multicolored (black/green, and yellow or red), rounder in shape (resembling a “beetle”).
- Brown stink bugs are brown, and nymphs are copper/brown. Adults are brown on the upper side, and yellow to light-green on the underside during summer. The brown stink bug is not the same as the invasive Brown Marmorated Sting Bug (BMSB). To date, we have not detected BMSB in corn or soybean (or fruit crops) in Wisconsin. An excellent identification guide to distinguish between stink bug species is available from the Iowa State University Department of Entomology here: http://www.ent.iastate.edu/soybeaninsects/node/144
Feeding and Damage Relationships in Corn and Soybeans
- When economic damage occurs in corn, it is has been reported on younger plants up to the V15 stage (small ear forming). This work was done in southern states on the southern green stink bug (Nezaraviridula). Not much has been reported on green stink bug in corn, probably because this species occurs in very low numbers in the south (and north) until late July or August when corn is usually on its way to maturity and other crops are more attractive to stink bugs.
- Stink bugs on corn are not an economic concern at this time, and no treatment thresholds are established. Insecticide application in corn for stink bug is not recommended, nor expected to recover yield.
- In Soybeans, stink bug nymphs and adults feed primarily on seeds and pods. (They will also feed on soybean stems, foliage and blooms). Punctures can be found as small brown or black spots. Direct feeding can lead to reduced seed quality (young seed deformed, undersized, possibly aborted under heavy stink bug pressure). Older seeds can be discolored or shriveled.
- Stink bug thresholds in seed beans are lower than grain soybeans.
- “Green bean effect” can result. This is an indirect effect of stink bug feeding, delaying plant maturity.
- Again, the damage described above is rarely reported in Wisconsin, – and when noted is likely to be more prevalent in field edges or sides.
Stink Bug Scouting and Thresholds in Soybeans
- Monitor several sites in a soybean field. This is important due to the aggregated field distribution (edge effect) of stink bugs.
- Check 5 different areas of the field (for example, 20 sweep net samples at each of 5 locations).
- Sweep net or drop cloth samples can be used. Sweeps are more appropriate for drilled, narrow row beans. A “shake sample” to dislodge bugs from the canopy on to a light colored cloth placed between rows is suitable for wide row beans.
- Combine nymphs and adults in sample total. Calculate stinkbugs per sweep (or per row foot) based on the whole field, and not an infested clump at one field edge or corner.
- Stink bug thresholds range from 1 to 3 bugs per foot of row as soybean pods begin to fill. Based on sweep net samples, for grain soybean 0.4 bugs per sweep (40 in 100 sweeps), and for seed beans 0.20 bugs per sweep (20 in 100 sweeps). (while pods are still green).
Stink bug yield and quality impacts are not usually significant in Wisconsin soybean. The information presented here will help you monitor the situation.
Green stink bug description
Also known as the name green soldier bug, this tiny creature has the zoological name Chinavia hilarious. It belongs to the family called Pentatomide. The green stink bug is found in the shades of green and yellow. The most common tints and hues found in this species include that of the bright green. This body color is accentuated by the addition of the small edges of red, yellow and orange. The body looks like a soldier’s shield. It is little stretched oval like structure that makes it look unique and different from many other species. The overall length of the body measures between 13 and 18 mm. The body also has three unique shaped antennal segments that make it easy to differentiate between the green bug and the other species falling under Nezara viridula. Unlike the pronotal margin in Acrosternum pennysylvancium, the green bug has a comparatively straight one. Beneath the thorax, just halfway to the metapleuron edge there are stink glands in the adults and the nymphs. A certain secretion with terrible smell is released from these glands. This liquid is of high industrial worth after it is dried. This dried form is used to overcome the smell of the acids.
Life cycle and biology
The green stink bugs start mating in the spring season. They are very active in this part of the year the bugs are seen during May and June or July and August. They taper off in the latter months usually by staying in the fruit trees. One generation is produced in one year. The warm springs make them more active. The first generation appears in June while the second one appears in the months of July and August. The life cycle of the green bug usually spreads over 45 days.
The eggs of the green bug are 1.4 mm by 1.2 mm in size. Their color at the early stage is yellow, but it gradually transforms into a green color. The final stage of these eggs is pink or gray. They lay their eggs in the clustered form. They are arranged in the double rows. They get attached to the food source.
The nymphs are small, black creatures. The nymphs start changing into green, yellow and red color when they start growing up. In the immature stage, they can be identified with the white spots that appear on their entire abdomen. The bodies are oval in shape and have wings that are not well developed for flying. After reaching the final instar, they start looking like the adults. The instars stay together due to aaa particular kind of oviposition behavior.
They are shield-shaped creatures with a pair of wings. They are 14 to 19 mm long and light green. There is a narrow yellow line around the pronotum and the head region. They suck plant fluids with the help of their mouthparts.
The life of this species depends upon several types of seeds and fruits. By taking in a sufficient amount of these. It becomes possible to have a sufficiently massive population. Green bugs pre upon several important vegetations. They mostly feed on tomato, black cherry, tobacco, elderberry, soybean, dogwood, peas, basswood, pear, pine trees, peaches, apple, eggplant, apricot, cotton, asparagus, corn, and beans.
The green stink bug is extremely dangerous for the commercial plantation like fruit trees. They have a severe impact upon the fruit causing the development to stop at various stages of the fruit development. The adults are fatal than the nymphs because the nymph movement is retarded and they are not very active either. The nymphs are not able to attack the trees that give fresh fruits like peaches. The adults lay their eggs in the season when they prey upon the grapes. The primary source of food at the time of appearance of the nymphs is the fruit extract of the mature fruit.after feeding on the fruit the bug injects the harmful juices into the fruit, which has negative implications for the growth and development of the fruit in general. After continuous attacks on the fruit, the quality of the fruit is severely affected. The seed quality is also badly impacted. Pathogens can make an easy way to into the affected fruit. As the bug damages the tissues of the fruit, the fruit suffers from a certain deformation that is known as cat facing. The surface becomes rough as the essential juices are drained out. Dimpling and scarring are another common forms of distortion caused due to the green bug. In some fruits, dimples appear in the skin.
How to get rid of the green stink bug physically
1. Vacuum the bugs up
An industrial vacuum is a great tool to get rid of the bugs. It is a very easy way to remove the bugs from the affected plant. After removing the bugs, it is critical to eliminate the bag from the vacuum as it can keep the stink for a long time leaving your vacuum useless. It is a technically sound way that involves little manual excursion to get rid of the bugs.
2. Wallop them with soapy water
The second easy to do remedy is to use any good dish detergent in a bucket of water. The bucket with soapy water has to be placed near the affected plantation. At this point, some manual effort is needed. The bugs are hand-picked and then thrown into the soapy water. It is a stink-free way of getting hold of the bugs.
3. Use an insect electrocution system
Bug zappers or the insect electrocution system is installed in any dark area. The installation instructions come in the manual. The device has to be operated at night to ensure that no harm is caused to anything else. These devices attract the bugs towards the bright light generated by the apparatus. As the insect comes closer, the insect gets trapped and then killed by the electric shock.
4. Spread fly tape along entryways
It is a hassle-free, convenient way of getting rid of the bugs that plague you. It is a kind of sticky stretch that is used to cover the places that allow the green bugs to invade your home. As the bug tries to cross the tape, the sticky solution does not permit it to go any further. Thus, the pace of spreading around reduces.
Green stink bug prevention
It is essential to take all preventive measures to keep away the bugs instead of using chemical ways later when they spread out.
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1. Seal your doors and windows
If you do not want the stinky green creatures to crawl into your domestic premises, it is suggested to seal all the doors and windows that are either broken or cracked. Sealing agents can be used to block the potential entry passages of the green bugs.
2. Patch up any holes
Sometimes cracks start appearing in the walls or any other parts of the building. It can happen because of the changing weather conditions, or the structure starts coming off itself. These cracks, holes and the openings become the entry points of the green stink bugs. To prevent them it is important to seal all such entry points. The best solution is to fill them with caulking.
3. Control your weeds
A garden can be a breeding and growing area for the green bugs. The more unwanted weeds in the garden, the more green bugs. The more the bugs, the more challenges you are likely to face. Get rid of the unnecessary weeds and keep away the bugs from your premises in a safe way.
4. Attract stink bug predators
Just like green stink bugs feed on several tiny creatures, many preys upon the green as their food. Get to know these predators and give a call to the predators who can kill the bugs but are not harmful to your attire. These include some plantations also.
- Stink Bugs 101: What Do Stink Bugs Look Like? (Plus 8 Facts)
- How to Kill Stink Bugs (Naturally) and Keep Them Away?
- Green Stink Bug: Interesting Facts, Damage & How to Get Rid of Them
- Everything About Brown Marmorated Stink Bugs （2018）
- 9 Best Brown Marmorated Stink Bug Repellents Worth To Buy
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“Keep a green tree in your heart and perhaps a singing bird will come.”
Aphids- Leaves sticky from small green bugs
Aphids are very small, soft-bodied insects with long mouth parts that they use to pierce stems, leaves, and other tender plant parts in order to suck out plant fluids. Most plants have at least one type of aphid that feeds on it during the growing season or an off season warm spell.
Aphids are small, soft insects that are typically wingless. They are almost always found in groups or clusters of overlapping generations. They can be seen without visual aid and are easily smeared or squished when touched or if a finger is wiped across them.
Other signs include the presence of honeydew. This shiny film coats leaves and the understory of trees as aphids excrete the excess sugar they consume. Wasps, bees, and ants can often be found feeding on this sugar source. Often times, leaves turn black when the honeydew is colonized by a fungus called sooty mold.
Curled leaves can indicate leaf curling aphids which feed on leaves causing them to curl up and create a protective envelope where they are well protected from predators and foliar treatment attempts.
There are many different species of aphids, some of which are host specific and others that feed on a wide host range. They produce multiple generations per year and are capable of growing their populations at rapid speed by reproducing asexually. Some females will birth upwards of 12 individuals in one day! Because of this amazing reproductive ability aphid populations can jump from insignificant to harmful levels in just a matter of a few warm days.
Once populations become too high, winged forms are produced and fly to colonize new locations. Some mate and lay eggs, which is a reliable way to survive the winter in harsher climates.
Typically, damage is minimal from leaf feeding aphids. Damage can become significant if populations spike causing leaf deformation and massive honeydew problems. This causes plants to stick to each other and promotes the growth of black sooty mold which decreases the capacity of trees to photosynthesize.
Some aphids, like the Bow Legged Fir Aphid, feed on the soft tissue of branch bark causing damage to limbs on Concolor Firs that can lead to weakened wood and possible dieback if left untreated for long periods.
The best management is to help trees stay healthy and strong so they are able to defend themselves from aphids without human intervention. Proper watering and regular soil treatments help to ensure this ability.
If populations spike, a dormant oil treatment can be made before bud break in late winter or insecticidal soaps can be applied during the growing season.
There are also a number of insecticides that can be sprayed on foliage or applied systemically through the roots or trunk. The systemic applications can be applied in the dormant season and control population outbreaks for the entire growing season. It’s important to rotate pesticides if aphid problems continue to arise on the same tree. This will reduce the chance of aphid populations developing resistance to insecticides.