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2015). These results suggest that the impact of H. halys in soybeans may be limited to the mid-Atlantic
and southern United States. However, in another study, Koch and Rich (2015) confirmed that caged
H. halys can affect yield components such as maturity and quality of early maturing soybean varieties
in Minnesota. Rich and Koch (2016) also showed that Rag1 aphid-resistant soybeans increased H. halys
mortality in no-choice tests. In choice tests, H. halys preferred Rag1 aphid-resistant soybean after 4
hours but not after 24 hours.
Adults of Halyomorpha halys have been observed feeding on wheat during the milk and soft dough
stages, which corresponds to the time when native stink bugs feed on wheat (Rice et al. 2014). So far
their impact on this crop has not been determined. In a study conducted in Minnesota wheat fields using
sweep net surveys during 2011 and 2012, 14 stink bug species were recovered. None was identified as
H. halys (Koch et al. 2016).
Halyomorpha halys attacks a wide variety of ornamentals (Hoebeke and Carter 2003, Bernon 2004,
Nielsen and Hamilton 2009b). Currently, it is known to feed and/or develop on at least 120 different orna-
mental hosts (Table 4.1) (Anonymous 2015b) and is capable of causing both indirect and direct damage
to plants (Hoebeke and Carter 2003, Leskey et al. 2012a). Indirect damage is characterized by stippling of
leaves followed by a scab-like appearance (Hoebeke and Carter 2003). Direct damage caused by this bug
feeding through the bark of woody ornamentals includes large amounts of sap flow, fluxes, and discolored
bark around feeding sites (Martinson et al. 2013). This type of feeding damage in ornamentals has not
been reported for other stink bugs (Panizzi 1997, Martinson et al. 2013). Feeding also attracts ants and
wasps to feeding sites in search of high levels of sugar available in the sap (Martinson et al. 2013).
4.5.3.3 Organic Agricultural Pest
There is no documentation of the economic impacts of Halyomorpha halys to the organic commu-
nity. However, organic growers cannot utilize synthetic pesticides and many Organic Materials Review
Institute (OMRI) approved materials, if effective, have limited residual activity; however, Cira et al.
(2017) showed that a combination of azadirachtin and pyrethrins significantly reduced egg hatch and
caused significant mortality of first and second instars. The authors also showed that azadirachtin and
pyrethrins and sulfloxaflor significantly reduced the percentage of first instars that molted. Morehead
and Kuhar (2017) further evaluated the use several OMRI approved material to control H. halys under
laboratory and field conditions. They found that only pyrethrins resulted in moderate toxicity using a
bean dip bioassay. Also, under field conditions, with one exception, none of the test materials, when
applied weekly, effectively reduced damage in tomatoes or peppers. The exception involved one harvest
date in peppers where the combination of pyrethrins and azadirachtin provided less damage that that
seen in the unsprayed control. H. halys has been difficult to control for organic growers, and current
research is investigating the use of trap crops, exclusion fabrics, and conservation biological control. One
such study conducted by Soergel et al. (2015) investigated the use of sunflower in pepper plantings as a
potential trap crop. They showed that significantly more nymphs and adults were present in peppers sur-
rounded by sunflowers than in those not surrounded by sunflowers. Despite this, no significant difference
in damage was found between peppers planted with or without sunflowers suggesting that their use might
not be a suitable control tactic. Nielsen et al. (2016b) evaluated the attractiveness of sorghum, Admiral
pea, millet, okra, and sunflower to H. halys in four Mid-Atlantic States. Sorghum was the most attrac-
tive followed by sunflower and okra. In the same study, the use of flaming, pheromone-baited traps and
the application of OMRI-approved insecticides were evaluated as management techniques. The use of
flaming was more effective than either of the other two techniques. Different types of physical exclusion
barriers as a protective measure also have been evaluated with mixed results depending on pest pressure,
barrier color, and screen size (Dobson et al. 2016).
4.6 Current Management Tactics
Management of Halyomorpha halys presents significant challenges to commercial growers for several
reasons. First, the broad documented host range of this bug shows that over 150 wild plants and crops, if