The comparatively mild
winter in 2015-2016 was
thought to result in higher survivorship of overwintering adult
BMSB
populations. However, captures in pheromone traps were
relatively low through
about mid-August, after which captures increased markedly to
levels that
exceeded those in 2015. Relatively low levels of Injury from
BMSB were reported
in apples through much of the season and there were few reports
of significant
injury to peaches at harvest. However, injury to apples
increased between late
August and September and there were reports of some orchards
sustaining
significant injury from this pest at harvest. Despite higher
BMSB captures
during late season in 2016 than in 2015, the numbers of adults
dispersing to
buildings in late September and October were not as high as
anticipated. In our
region, the Asian parasitoid of BMSB eggs, Trissolcus
japonicus, has been detected in MD, DE, DC, VA, and WV and
appears to be
well-established in some locations. As in 2015, there appeared
to be fewer
issues with outbreaks of woolly apple aphid in 2016, although
some orchard
consultants reported problems with San Jose scale. Since it has
been a
long-standing policy of tree fruit Extension Specialists to not
recommend
post-bloom use of pyrethroids, due to their disruptive effects
on natural
enemies of secondary pests, we have not included them or
pre-mixes containing
them in most post-bloom cover sprays for pome fruit. However,
the most
effective products for BMSB continue to include Belay
(neonicotinoid), products
containing permethrin, Baythroid, Danitol, and Warrior II
(pyrethroids), Lannate
(carbamate), and the pre-mixes Endigo ZC and Leverage 360, both
of which
contain a pyrethoid. Section 18 Emergency Exemptions were issued
again in 2016
for the pyrethroid, bifenthrin (Bifenture, Brigade) and the
neonicotinoid,
dinotefuran (Scorpion, Venom), which are considered very
effective against
BMSB. Renewals of the Section 18 Exemptions for these products
will be sought
for the 2017 season, but until notified of an approval by
Cooperative Extension
personnel, do not use bifenthrin or dinotefuran in apples,
dinotefuran in
pears, or bifenthrin in stone fruit. Furthermore, while
dinotefuran is
registered for use in stone fruits, the highest labelled rate
may not provide
acceptable control of BMSB. Do not use dinotefuran in stone
fruit at the higher
rates permitted by a Section 18 until notified of an approval.
Since the
residual effectiveness of products for BMSB control may vary
considerably and
not extend beyond several days, particularly following rain, we
continue to
recommend the use of alternate-row-middle applications at about
7-day intervals
during much of the growing season. Peaches and nectarines are
vulnerable to
injury from BMSB from fruit set onward while injury to apples is
typically
detected from about mid-June onward. For additional information
about BMSB and
its management in tree fruit orchards, see the following on the
StopBMSB.org
website: www.stopbmsb.org/stopBMSB/assets/File/BMSB-in-Orchard-Crops-English.pdf