The crop situation is all over the board in Alabama. Fields
in the Gulf Coast region have received rains in something like 30 of the last
37 days, while fields in North and Southeast Alabama are rated as abnormally
dry and in some cases, in a moderate drought (link).
Thus far, cotton in Central and East Central Alabama looks really good.
Retention has been high and after a slow start, rains have picked up and the
crop is rolling.
Cotton
Dirty bloom with TPB nymph
As we have been discussing on the blog, the bug complex is
what we need to be scouting for from this point forward. We have observed and
have received reports that plant bugs are a little bigger player in the complex
at this point in the year than we normally expect. We went to a cotton and corn
field day at the research station at Fairhope yesterday (8/4) and plant bugs
were the big topic. Scouts and consultants reported heavy numbers of plant bugs
and dirty blooms in fields, particularly those around corn. Plant bugs have likely
already moved out of corn, but heavy egg lay when they moved, combined with rains
making getting into the field difficult and we have a situation where an
imbedded population of plant bugs takes hold. We have seen similar situations
in the TN Valley, although reports are that some fields are in good shape following
applications over the past 10-14 days.
Overall, reports are coming in that the bug pressure is
field to field in some areas. In other words, some fields have high pressure
and other fields we aren’t seeing much. This drives home the importance of
having someone looking and scouting to ensure we have economic infestations
prior to making applications.
The spider mite situation in the Wiregrass seems to be continuing.
Lack of rain and hot weather is exacerbating things. In these situations, we
need to make sure we are scouting for other pests and only treating when needed,
as automatic sprays may unnecessarily flare mites. If mites are in the field
and stink bugs or plant bugs require attention, don’t hesitate to spray…but
consider tank-mixing a miticide to help keep mites in check.
Soybeans
Our soybean looper traps in Central Alabama (near Tallassee)
picked up this week. We collected nearly 500 moths over a 7-day period. It is time
to start looking and thinking about SBL in Central and South AL. Keep in mind
our thresholds are 19 SBL per 25 sweeps -OR- to avoid 20% defoliation until R6.5.
We are also seeing a mix of green cloverworms (GCW) and velvetbean caterpillars
(VBC) in the mix as well. In fact, as we were typing this blog (8/5), we received
a report of economic infestations of VBC and defoliation in late planted beans
in SW Alabama. Identification is critical, because GCW and VBC are easily
controlled with pyrethroids or IGRs (Dimilin, Diamond), while SBL require a
shift to the “newer” insecticides (Prevathon/Vantacor, Besiege, Elevest, Intrepid
Edge, Blackhawk) due to resistance.
As our soybean crop continues to develop and fill pods,
stink bugs are infesting fields. We are still getting calls about redbanded
stink bugs, particularly in the Black Belt. Thus far, they have not made it to
the TN Valley, and it is probably unlikely that they will…BUT never say never. In
North Alabama, we need to be scouting for the traditional stink bug complex.
Our threshold is 4 stink bugs per 25 sweeps. This is aggressive, but in a validation
study we did last year, this threshold made us more money than a more relaxed
threshold of 6 or 9 per 25 sweeps.
Deer Survey
In response to a farmer request, the Alabama Extension
Agronomics Crops Team is conducting a survey to better understand the impacts
of deer population on crop production. Please take a few moments to help us
collect information to try to use to figure out ways to mitigate deer losses in
your row crops.
You can take the anonymous survey here (link).
Take Home Points
Keep scouting fields, the situation is dynamic in Alabama’s
cotton and soybean fields. “Boots on the ground” help us to get the highest
return on investment for insecticide application decisions. Be prepared to
treat when needed, but only when needed.
If you would like to provide reports or observations on the
insect situation from your region, please let us know. You can reach Scott
Graham at 662-809-3368 or scottg@auburn.edu or
Ron Smith at 334-332-9501 or smithrh@auburn.edu.
As always, if we can ever be of any help, please let us know.
