The Alabama row crop insect control season is rapidly winding
down. The few areas that still need attention for a few more weeks are as
follows. We need to protect bolls on June planted cotton from stink bug injury
until the bolls are approximately 25 days old. We still have plenty of time
left in the season to mature small bolls that are present from blooms the last
week of August. On soybeans, stink bugs continue to reproduce and feed on pods.
Late planted, June to early July, soybeans will be susceptible to stink bug
feeding for several more weeks. Stink bug adults will leave other crops when
they mature and seek out late planted soybeans as their last host before heading
for overwintering sites. I expect to see high numbers of stink bugs in many of
these late maturing soybean fields. The good thing is that one application to
economic levels of stink bugs in both cotton and soybeans made now should hold
populations below damaging levels for the remainder of the season. Stink bug
populations currently contain both the brown and southern green species. A high
rate of most pyrethroids on soybeans should give adequate suppression. Kudzu
bug adults are still present in many soybean fields but they are not as
numerous in most fields as they were back a month or so ago. Their numbers
seemed to have peaked in April and May planted beans back in the late June to
early August window.
Overall 2013 has been a light insect year in Alabama for
most species. A summary of what I have observed is the following. For cotton,
thrips were moderate to heavy. However, their movement from wild hosts to
cotton occurred in May instead of April. Therefore, their damage period
coincided with our mid-planting period cotton instead of the earliest planted
as happens most seasons. Plant bugs, aphids and spider mites were very light
overall. Bollworms and tobacco budworms were low to nonexistent, even in fields
of conventional cotton. I have conventional cotton on three research stations
spread across the central and southern areas of Alabama. One had to search very
hard all season to find a single larva or damaged fruit. Stink bugs were the
only cotton insect that occurred at damaging levels in most fields in-season.
In soybeans, Kudzu bugs were extremely heavy in many early
planted soybean fields. This was the first year that many soybean growers have
had to deal with the Kudzu bug. Others will likely have their first experience
in 2014. When all is said and done, I believe we will be able to handle this
insect with one, or at most two, well timed sprays. Late maturing beans will likely
still see a big buildup of stink bugs in coming weeks as other crops mature and
dry down. The foliage feeding complex of green cloverworms, velvetbean
caterpillars and soybean loopers have been very light in 2013. This follows the
most widespread infestations of the past 40 years last season. Podworms have
been very light in soybeans for the past two seasons.
This has been a very unusual year rainfall wise. This may be
the only season during my 41 years here as our Extension Entomologist where we
had too much rain.
With these comments we will end our in season
blogs unless something unusual shows up. I hope my comments have been helpful
to those of you that are receiving them. Hopefully we can continue this blog,
the Syngenta Insect Hotline, and our tweets during the 2014 season.
