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Posts Tagged: brown marmorated stink bug

Brown marmorated stink bugs expected to have a 'banner year'

White stripes on the bug's antennae are a dead giveaway the insect is brown marmorated stink bug.
The California population of brown marmorated stink bugs, a pest introduced into the state from its native Asia, continues to spread and increase in and around Sacramento, said a UC Agriculture and Natural Resources (UC ANR) expert who appeared today on Capitol Public Radio's Insight program with Beth Ruyak.

Chuck Ingels, UC ANR Cooperative Extension advisor in Sacramento County, said BMSB was first spotted in 2013 in Sacramento and each year the numbers have grown. This year, the warm spring gave BMSB a head start, portending significant population growth in August and September 2015.

"We're very concerned about tree crops, tomatoes, peppers, corn, beans and other crops," Ingels said. On a bright note, he said California farms do not have forests surrounding them like farmers back East, where growers have been dealing with BMSB since the the mid-1990s. "BMSB is an arboreal species. They live in trees and then come into the farm. We're not sure how much of a problem it will be on farms here (in California)."

Ruyak asked whether any control solutions can be found in the pest's native territory or from farmers back East. 

"Growers are using pesticides back East," Ingels said. "There is a parasitoid from China that is under study in labs to see if they pose a problem for native stink bugs and other bugs."

One possible solution for dealing with the pests in gardens is planting sunflowers. Because BMSB are strongly attracted to sunflowers, they may draw the pests away from other crops and allow gardeners to monitor the BMSB presence. On the other hand, sunflowers may actually attract BMSB to the garden, where they could feed on vegetable crops.

BMSB feeds with a mouthpart called a "proboscis," stinging developing fruit 1/4 to 3/8 inch deep and sucking out its juices. As the fruit ripens, it hardens and deforms, becoming inedible.

Read more about BMSB, how to identify it, and methods to manage it around homes and gardens in the UC IPM Pest Note: Brown Marmorated Stink Bug.

Posted on Wednesday, July 8, 2015 at 11:18 AM

Nightmare in midtown: Brown marmorated stink bugs

A Sacramento report considers brown marmorated stink bug worthy of a Halloween creature feature.
A population of invasive brown marmorated stink bugs have settled in Sacramento's mid-town, a development that Sacramento Bee writer Debbie Arrington says is "worthy of a Halloween creature feature."

"Wow, I'm being overwhelmed with calls about brown marmorated stink bugs getting into people's home, as well as restaurants and businesses," said Chuck Ingels, UC Cooperative Extension advisor in Sacramento County. "It's that time of year again!"

When days get shorter and cooler, the BMSB start looking for a place to spend the winter. Frequently, that's inside homes and buildings.

Ingels told the reporter he is keeping track of the BMSB invasion. Residents are asked to fill in an online survey to report BMSB finds. For identification help, residents may deliver BMSB in a sealed plastic bag or container to the UCCE office, 4145 Branch Center Road, Sacramento, or they can email clear photos to

Ingels said fairly large populations of BMSB have been found in Citrus Heights near Auburn Boulevard and River Park north and west of CSU Sacramento.

"Most of the others are single finds," he said.

For more information on BMSB identification and management, read a Pest Note posted by the UC Integrated Pest Management program.

Posted on Monday, October 27, 2014 at 10:38 AM

Invasive pests of concern for California’s urban agriculture systems

Every year, California receives, on average, six new exotic invasive pests of concern; that's about one new pest every 60 days. These may be plants, insects or other arthropods, mollusks, plant pathogens such as fungi and bacteria, vertebrates, or any other organism not native to our state and with the capacity to negatively impact agriculture, urban environments and/or natural ecosystems. These invasive pests enter California on plant material and other biological substrates, as hitchhikers on trade goods and in ship ballast water, and sometimes even because of smuggling operations. Without the natural enemies that kept them in check in their native lands, they are free to reproduce and wreak havoc. Such pest invasions may then lead to destruction or alteration of habitat, loss of agricultural trade revenues, pronounced losses in agricultural production, and increases in pesticide applications.

The best way to combat such invasions may be through robust exclusion, inspection, early detection, and quarantine programs. Once established, they are best managed using classical and conservation biological control and the decision-making process of integrated pest management (IPM), described in detail in an earlier blog post. Urban agricultural environments are not immune to these invasions and may even be more at risk since urban environments contain many likely routes of introduction and have often been identified as point sources for invasive pests. In this article we will review the biology, ecology, and management of three recent pests that may increasingly be found in urban gardens and other urban ag environments.

Asian citrus psyllid and the huanglongbing pathogen: First found in Southern California in 2008, the Asian citrus psyllid (ACP), Diaphorina citri, feeds on citrus and related plants in the Rutaceae family, sucking sap and injecting toxins that distort new growth. Even worse, however, the psyllids can transmit an incurable citrus disease, huanglongbing (HLB) or citrus greening, from plant to plant. Currently, the psyllid's distribution is limited to urban Southern California and small parts of the citrus production areas in the San Joaquin Valley. The bacterial disease HLB is thankfully not established in California, but it has been detected (and eradicated) in urban Los Angeles County and intercepted recently at a port-of-entry in San Mateo County. If you grow citrus, make sure to check new growth during spring and fall to look for psyllid nymphs and the distinctive waxy tubules they excrete. Report any suspect finds to your County Agricultural Commissioner's office. Make sure to comply with the management tactics prescribed by these authorities; trees across the state depend on it. To learn more about ACP, HLB, management tactics, and other related topics please visit the following links: 

PESTNOTES - UC IPM Online: Asian Citrus Psyllid and Huanglongbing Disease

Center for Invasive Species Research: Asian Citrus Psyllid

UC scientists release a natural enemy of Asian citrus psyllid


Brown marmorated stink bug (BMSB): This large (5/8”) stink bug from eastern Asia has been an established pest in the eastern United States since 2001. Though it has been intercepted many times in California over the years, probably because of its ability to hitchhike on and in outdoor household items (such as patio furniture) and firewood, it has only recently (sometime between 2006 and 2013) become established in the state. The BMSB, Halyomorpha halys, is a key agricultural pest, reportedly attacking over 100 plant species using piercing mouthparts to suck juices and inject tissue-damaging enzymes. Damage is expected to be worst on pome fruits (apples, pears), stone fruits (peaches, nectarines), legumes, corn, tomatoes, and peppers. Stink bugs are known to aggregate in large numbers in fall, sometimes entering homes and other structures to escape harsh winter conditions. BMSB can be distinguished from several native stink bug species by two white bands on the antennae. The current distribution in California is unknown, so if you think you find BMSB you should contact your County Agricultural Commissioner's office to confirm and document its presence. To learn about BMSB identification and management, please visit the following links:

PEST NOTES - UC IPM Online: Brown Marmorated Stink Bug 

Pest Alert - UC IPM Online: Brown Marmorated Stink Bug

Center for Invasive Species Research: Brown Marmorated Stink Bug


Bagrada bug: This small (1/4”) relative of the BMSB, also called the painted bug, preferentially attacks many plants in the mustard family (Brassicaceae), including crops such as broccoli, Brussels sprouts, cabbage, and kale, as well as related ornamental plants such as sweet alyssum, stock, and candytuft. Native to Africa, bagrada bug was first found in urban southern California in 2008 and has been slowly moving up the coast and north within the Central Valley.  Most recently, the pests has become established within many urban gardens in the San Francisco Bay Area and in small farms in the Capay Valley. Damage is most severe on newly-planted seedlings; stunting and death are common when infestations are large. The brightly-colored (orange, black, and white) bugs are sometimes confused with the similarly-colored harlequin bug, a common American species, though these are three times larger and lack any white coloration. Similar to the BMSB, bagrada bugs may aggregate and enter structures and other protected areas during winter. As with the other invasive pests discussed, if you think you find bagrada bug in your area, then please alert your County Agricultural Commissioner's office, especially in areas where these insects have yet to be found. To learn more about bagrada bug identification and management, please visit the following links:

PEST NOTES - UC IPM Online: Bagrada Bug

Pest Alert - UC IPM Online: Bagrada Bug

Center for Invasive Species Research: Bagrada Bug

Posted on Thursday, September 25, 2014 at 1:36 PM
  • Author: Andrew M Sutherland, SF Bay Area Urban IPM Advisor

National stink bug story features UCCE expert's quotes

Brown marmorated stink bugs huddle together on a tree limb in Sacramento. (Photo: Baldo Villegas)
Epoch Times, a website touted to reach 35 countries in 21 languages, released a national roundup about brown marmorated stink bug which featured colorful quotes from Chuck Ingels, UC Cooperative Extension advisor in Sacramento County.

Reporter Zachary Stieber opened the story with the new stink bug find in Sacramento.

“This is one of the worst invasive pests we’ve ever had in California,” Ingels said.

Ingels painted a word picture to help readers envision the BSMB's unsettling behavior during the cold winter months.

“These bugs aggregate in such numbers that there are reports of people using manure shovels and five-gallon buckets to dispose of them,” Ingels said. “The strong, unpleasant odor the insects emit when disturbed makes cleanup still more daunting.”

The story said BMSB was:

  • The "bug of the year" in Dayton, Ohio
  • Seen in “exploding numbers” at research plots in central Maryland
  • Found in high population densities this year in nearly every region of Oregon
  • Living in highest concentrations in Pennsylvania, Delaware, New Jersey, Maryland, Virginia and West Virginia

Stieber also embedded the following YouTube video of a stink bug nymph feeding on a green tomato:

Posted on Friday, October 4, 2013 at 11:15 AM

“Super pest” takes hold in Sacramento neighborhood

A resident in the Sacramento infestation site shot this photo of brown marmorated stink bugs aggregating on a tree. (Photo: Baldo Villegas)
A well-established and reproducing population of brown marmorated stink bugs (BSMB) has been found in a Midtown Sacramento neighborhood, reported Chuck Ingels, UC Cooperative Extension advisor for Sacramento County. The infestation seems to be centered around 13th St., south of Capital Park. This is the first reproducing population in California outside Los Angeles County.

Ingels said he had no difficulty finding the pests on tree foliage and flying around when he visited the site last week.

“This is one of the worst invasive pests we’ve ever had in California,” Ingels said.

Brown marmorated stink bug affects many different crops and is a serious residential problem. It moves around easily, so can be expected to spread. It can fly up to a half mile at a time and also travels long distances by hitching rides in vehicles or inside furniture or other articles when they are moved, often during winter months. As a result, most new infestations are found in urban areas.

Brown marmorated stink bugs are native to China, Japan and Korea. They were first documented in the United States in Pennsylvania in 2001, but was likely established there several years earlier. The pest has spread throughout Pennsylvania, is believed to be established in at least 15 states, and has been found occasionally in more than a dozen additional states. In 2004, BMSB made its way to Oregon and is now established in northwest Oregon and a portion of Southern Washington. The National Agricultural Pest Information System maintains a map showing current infestations, but it does not yet show California finds. The pest has been present in Los Angeles County for 6 years.

BMSB feeds on dozens of California crops, including apples, pears, cherries, peaches, melons, corn, tomatoes, berries and grapes. Feeding on fruit creates pock marks and distortions that make the fruit unmarketable. In grapes, berries collapse and rot increases. Wine tasters have been able to detect stink bug odor in wines made from grapes that had 10 bugs in a 35-pound lug. It is also a pest of many ornamentals, especially the fruit-bearing trees, princess tree (Paulownia tomentosa), common Catalpa (Catalpa bignonioides) and tree-of–heaven (Ailanthus altissima).

In addition to the damage caused by the BMSB feeding, the “true bug” can cause disturbing problems for homeowners in the winter. When the weather cools down, bugs migrate in droves to sheltered areas, including inside homes and buildings.

“These bugs aggregate in such numbers that there are reports of people using manure shovels and five-gallon buckets to dispose of them,” Ingels said. “The strong, unpleasant odor the insects emit when disturbed makes cleanup still more daunting.

 BSMB is a pest in its homeland, but is mostly controlled by parasitic wasps. USDA researchers have collected parasitic wasps in Asia, but they must be tested extensively before they can be released in California, a process that will take until 2016.

“Parasitism is our best hope for reducing populations,” Ingels said. “Chemical control of BMSB is very challenging.”

Ingels said the best way to keep them out of homes is to exclude them by sealing off any potential entry points, especially around window air conditioning units. Insecticides that have been shown to be effective in the lab are often less effective in the field.  In and around the home, insecticides that have efficacy are mostly pyrethroids and neonicotinoids, both of which can have harmful off-site effects.

Pesticides showing efficacy on farms also include organophosphates and carbamates. But growers have worked hard to develop effective Integrated Pest Management programs, and the use of these broad spectrum sprays will set these programs back. There are also pest resistance concerns with increasing use of these products.

A close-up of aggregating brown marmorated stink bugs. (Photo: Baldo Villegas) )
Control for organic growers and home gardeners will be most troublesome, and involves the use of row covers, trap crops, pheromone traps, and predator insects. Ingels is asking growers to be on the lookout for BMSB.

“Because they are strong fliers, it’s just a matter of time before they reach farms,” Ingels said.

The pest can be distinguished from ordinary brown stink bugs by its larger size, marble-like coloring on its shield and white markings on the extended edge of the abdomen. BSMB also has distinctive white bands on the antennae and legs. The UC Integrated Pest Management Program has posted a video on YouTube to aid in identifying the pest. (The video is also embedded below.)

Traps with sex pheromones or other attractants can be used to monitor for the pest, but they are often poor at trapping the bugs even when populations are high. The best monitoring method is to inspect foliage throughout the year, and larger branches in late summer and fall for aggregating bugs. A quick method is to beat foliage over a piece of cardboard or sheet. If suspected BSMB are found, place some in a container and note where and when they were collected. Take the sealed container to the county agricultural commissioner or local UC Cooperative Extension office.

The following UC IPM video was created to help identify brown marmorated stink bug:

Posted on Wednesday, September 18, 2013 at 8:34 AM

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