Statement of Issue: The brown marmorated stink bug, Halyomorpha halys Stål (BMSB) is a highly polyphagous stink bug of Asian origin. In its native range of China, Korea and Japan, it is considered a periodic agricultural pest of soybeans, tree fruit and various ornamental and vegetable crops. The brown marmorated stink bug is also a nuisance pest in these countries due to its overwintering behavior of entering enclosed structures such as residences in large numbers each fall. Since its introduction into the United States around 1996, it has spread to all but six states and the District of Columbia. Halyomorpha halys has also established populations in Canada, numerous European countries, South America and potentially southern Africa. It has also been intercepted in other countries such as New Zealand and Australia. In the United States BMSB has become a homeowner nuisance wherever it has established and in the eastern United States H. halys become a severe agricultural pest on both conventional and organic farms with little (insecticide use) or no management options. Halyomorpha halys is an emerging pest in Southern and Midwestern United States. In the western United States growers in agricultural areas of California, Oregon and Washington where BMSB is becoming established are also concerned about its impacts because it has been shown to be damaging tree and nuts crops in these areas. In the United States where BMSB is currently a pest, it also attacks a wider range of agricultural crops than in Asia. Currently, damage is seen in numerous vegetables, tree fruit and field crops, and in nurseries. Due to this, failure to address this issue on a regional/national basis will result in severe losses in a variety of cropping systems including peaches, apples, soybeans and peppers resulting in economic hardships by growers and potential farm failures.

Need: In 2010, in response to severe losses in the mid-Atlantic United States due to BMSB, Drs. Tracy Leskey (USDA ARS) and George Hamilton (Rutgers University) created the Brown Marmorated Stink Bug Working Group via a grant from the Northeastern IPM Center. The working group’s goals were to bring together researchers, growers and others with the intent to discuss the situation and identify needs research and extension needs and priorities. The first meeting generated a long list of needs and priorities. They can be found at http://www.northeastipm.org/working-groups/bmsb-working-group/priorities-and-reports/. Due to continued funding from the Northeastern IPM Center, this group continues to meet and has grown to over 80 members from throughout the United States. Each time the group meets the list of priorities/needs are discussed and modified. As a priority is met it is removed. New priorities are added when needed. This proposal's objectives reflect current needs established by the working group and will be modified during the life of the project to reflect changes in priorities as identified by the working group.

 A multi-state approach to this issue is warranted given the heavy losses incurred by agricultural producers in the eastern United States since 2010. In 2010, this insect’s presence in mid-Atlantic apples resulted in $37 million in losses (American/Western Fruit Grower 2011) and in the tree fruit growing regions of Virginia and West Virginia damage approached 90% (Leskey & Hamilton 2010). Organic producers in this area observed similar amounts of damage to numerous fruits and vegetables. In 2011 and 2012, comparable damage levels were again observed in these and other eastern states and crops (apples, pears, peaches, tomatoes, peppers, grapes, brambles sweet and field corn and soybeans) from Virginia to New York.  As a result of the current multistate project (NEERA 1306) and several USDA grants (OREI – 1, SCRI – 2) obtained by its members progress has been made in the management of H. halys resulting in damage reductions in tree fruit and vegetables.  However, these reductions continue to be the result of heavy insecticide use by growers and have resulted in outbreaks of secondary pests previously managed by natural enemies.

 Continuing the current multi-state project to address the on-going needs currently identified by the BMSB working group and others will bring together researchers already working on this issue in the Northeast and other parts of the United States once a year to discuss, identify, and adjust research needs and priorities, and present progress updates. This approach will also allow participating researchers to coordinate their activities to avoid duplication. Finally, since this insect has spread throughout the United States, creating a multi-state project has the potential to bring together researchers from the northeast, from other geographic regions and from other cropping systems not present in the Northeast (cotton, nuts, etc.).

Justification: The brown marmorated stink bug was first observed in the United States in Allentown, PA around 1996 but was initially misidentified as a native pentatomid species. Following correct identification in 2001, it has been found in over 40 states. In several eastern states, its presence in agricultural crops has been confirmed in 2009 and was documented causing severe damage to apples, peaches, pears, peppers and tomatoes. In 2010, 2011 and 2012 damage by this insect was also observed in brambles, field corn, grapes, ornamentals, soybeans, and sweet corn. 
 
Traditionally, management of stink bugs in soybeans, tree fruit and horticultural crops was accomplished through the use of targeted applications of organophosphate insecticides. However, with the passage of the Food Quality Protection Act in 1996, these materials have been slowly phased out resulting in increased damage by stink bugs in these crops. The addition of BMSB with its high rates of reproduction and survival puts these crops at greater risk. Many of the insecticides currently available to growers have variable effects (limited knockdown, recovery once treated, etc.) on resident populations and little or no residual effects on future invaders into treated fields and orchards. In the laboratory pyrethroid insecticides, the replacement for organophosphate insecticides in many cases, exhibit high levels of toxicity to the brown marmorated stink bug fifth instars and adults as do various neonicotinoid insecticides (imidacloprid and dinotefuran). Testing under field conditions has shown that pyrethroids such as bifenthrin to be the most efficacious. Prior to BMSB becoming a problem, pyrethroid use was discouraged in tree fruit and vegetables because of their negative effects to natural enemies. Today, due to the issues mentioned above, in many cases growers continue to rely on weekly applications of pyrethroids and neonicotinoids to manage BMSB thus abandoning 40 years of IPM program development. This use pattern has caused secondary outbreaks of pest such as the wooly apple aphid, San Jose scale and European red mits that were previously controlled by natural enemies putting growers on a "pesticide treadmill" that could lead to complete failures of management programs for BMSB and other pests.

In Asia, the brown marmorated stink bug is attacked by several egg parasitoids and one species of tachinid fly. However, as is customary with newly introduced species, natural enemies are rarely introduced at the same time. Two egg parasitoids and a tachinid fly have been observed attacking the brown marmorated stink bug in Delaware, Maryland, Pennsylvania and New Jersey but are generalist natural enemies and therefore not specific to the brown marmorated stink bug. Several native predators, including minute pirate bugs, ladybugs and spiders do attack BMSB. However, as with native parasitoids their impact has been limited. The use of microbial agents is another potential non-chemical control method. However, to date, screening for possible candidates with toxicity to the brown marmorated stink bug has had limited success. Exploration in Asia to find possible biological control agents has identified several potential parasitoids. One, Trissolcus japonicus, a highly effective egg parasitoid of BMSB in Asia, is currently in quarantine undergoing host specificity testing.  In the last 3 years, naturally occurring populations of this parasitoid (i.e., genetically distinct from the strain in quarantine) have been found in several eastern states and in Oregon and Washington. These finding have resulted in the need to investigate in the field their impact on H. halys and other native stink bugs, and how best to use them for control of BMSB in agricultural situations. 

In addition, wherever, the brown marmorated stink bug occurs it has become a severe residential nuisance pest. Currently, while progress has been made as a result of the current multistate project there are still no adequate pest management alternatives to prevent overwintering brown marmorated stink bug adults from entering residences in areas where they occur. Current recommendations for caulking of windows and/or the sealing of cracks and voids in exterior walls, eaves, etc. and the limited use of insecticides on external building surfaces can provide limited control but are not 100% effective. Unfortunately, homeowners, commercial building managers and pest control professionals continue create their own potential solutions through the illegal insecticides in attics and blanket treatment of exterior surfaces and interior walls with insecticides. These practices pose health risks to homeowners, their families and the environment.