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were more attractive to overwintering adults than those with white, red, green, gray or tan exteriors; that
stone or wood exterior-sided homes were more attractive than metal, brick, stucco, vinyl or cement exte-
riors; and that structures in rural areas attracted significantly more H. halys than those in urban areas.
To answer the question regarding settling preference, Inkley (2012) recorded the location of the over
26,000 adult Halyomorpha halys found in a residence (see above) between January to June. He found
that within the structure, unfinished attic crawlways had the highest populations (50.2%) compared to the
first and second floors of the building (40.4%) and the basement (9.4%).
In populated areas, as local populations of Halyomorpha halys begin to increase, the general public also
can be impacted because of feeding by these bugs on ornamentals and backyard vegetable and tree-fruit
plantings (Bernon 2004, Hamilton 2009, Nielsen and Hamilton 2009a, Martinson et al. 2013, Sargent et al.
2014). In response to public concerns about the impact, traps containing aggregation pheromones attrac-
tive to nymphal and adult H. halys have been developed and tested (Khriminan et al. 2008, 2014; Nielsen
et al. 2011; Leskey et al. 2012d, 2015a; Sargent et al. 2014). Sargent et al. (2014) evaluated the use of these
pheromone traps in tomatoes grown in homeowner gardens and, surprisingly, found that gardens without
traps were no more likely to have H. halys feeding on tomato fruit than those with traps. However, gardens
containing traps sustained significantly more damage to tomato fruit than gardens without traps, and indi-
vidual tomato plants near the traps had more bugs present on the fruit. This phenomenon (i.e., plants near
pheromone traps having higher numbers of H. halys and higher damage levels), has been observed in other
crop systems such as peaches and apples (Anne L. Nielsen, unpublished data; Morrison et al. 2015).
Traps developed to catch adults of Halyomorpha halys also have been developed for indoor use. Several
utilize light as an attractant. Aigner and Kuhar (2014) evaluated the efficacy of several traps using citizen
scientists in Virginia during the winter and early spring of 2012 and 2013. They compared the use of two
commercially available traps (Strube’s Stink Bug Trap – 2012 only, Rescue® Stink Bug Trap) and two
homemade traps (aluminum foil water pan trap; 2-liter bottle trap with LED light). Their results indicated
that the water pan trap caught significantly more adults than the Strube, Rescue® and 2-liter bottle trap in
2012 and the 2-liter bottle trap and Rescue® trap in 2013. (The Strube trap was excluded from the study
in 2013 because the company ceased production of trap in 2012).
Recently, the use of pheromone traps inside and outside man-made structures during the overwin-
tering period has been investigated (Morrison et al. 2017a). In this study, the authors examined when
Halyomorpha halys responds to pheromone during late winter and early spring, whether or not phero-
mone traps can be used to monitor for H. halys indoors, and whether or not pheromone traps can be used
as an indoor management tool. Over a 2-year period, their results showed that adults begin responding
to the pheromone in the spring following a critical photoperiod of 13.5 h, that trap captures could not be
correlated with visual counts indicating their use may not be an effective indoor monitoring tool, and
because only 8-20% of the known adult population responded to the pheromone-baited traps, these traps
would not be an effective indoor management tool.
Halyomorpha halys’ overwintering behavior also has become an issue for international commerce
with countries imposing restrictions such as fumigation or heat treatments to kill specimens present in
shipments prior to importation (Thompson 2014, Australian Government 2015). With heat treatments,
the primary question has been what temperature should be used. Aigner and Kuhar (2016) attempted to
answer this question using a series of different temperatures and periods of exposure under controlled
conditions. They found that 15 minutes of exposure to 50°C was adequate to provide 100% mortality.
After one hour of exposure, 45°C provided 100% mortality; after 4 hours, 42°C resulted in 92.3% mor-
tality. The authors also examined mortality under field conditions using vehicles waiting for export using
15-minute exposure to 40°C, 50°C, and 60°C. They found that 50°C was sufficient to kill 100% of the
adults placed either under the driver’s seat or in the engine compartment.
Today, as populations have increased in urban areas and subsequently spread into agricultural areas,
Halyomorpha halys has become a severe agricultural pest (Leskey et al. 2012a, Rice et al. 2014).
4.5.3.2 Conventional Agricultural Pest
The first documented agricultural damage in North America by Halyomopha halys was reported by
Nielsen and Hamilton (2009a) but actually occurred during 2006–2007. They noted the presence of