We are beginning to see some open bolls across south and central Alabama, the end is in sight. Not much has changed over the past week with our cotton insect situation. We are still fighting the bug complex in many fields across Alabama. In addition to tarnished plant bugs and stink bugs, we are also starting to observe some clouded plant bugs and leaf-footed bugs as well.
Cotton
SLWF
We are still in the early stages of the silverleaf whitefly
(SLWF) situation in our areas with historic outbreaks (some parts of the Wiregrass).
It is still not time to panic, but there are some fields infested that need to
be watched.
Fields to be alert of include any of or a combination of the
following:
- Late planted
- Drought stressed (hot, dry weather and/or dryland)
- Low beneficial insect populations (fields with recent insecticide applications)
- Hairy leaf varieties
Below is a copy of the SLWF handout from our colleagues who
have a lot of experience fighting these critters at UGA.
SLWF Handout - Click to Enlarge |
Bug Complex
While the presence of clouded plant bugs doesn’t necessarily
change our insecticide recommendations, the presence of leaf-footed bugs would.
In general, pyrethroids do not provide as good of control of leaf-footed bugs as
the organophosphates do. That leaves us with 6 oz of Bidrin or 0.75 lbs of
acephate. Due to the silverleaf whitefly (SLWF) situation in the historic SLWF
areas (some parts of the Wiregrass), I would avoid Bidrin at this point and go
with acephate. While we still don’t fully understand the reason, Bidrin really
seems to exacerbate a SLWF infestation. In areas outside of this localized
situation, Bidrin and acephate are both in play, depending on the availability
of each.Adult leaf-footed bug
Many of the people we have talked to have said they are
getting ready to put out their “clean up shot” and walk away. Another season is
beginning to wind down, but we need to keep scouting our later planted cotton
and be prepared to protect bolls as needed.
Soybeans
Defoliating caterpillars (soybean loopers and velvetbean caterpillars)
continue to build and require treatments in fields across central and south Alabama.
We are watching traps closely in north Alabama to monitor when populations should
be expected there as well. In addition to caterpillars, we are still fighting
stink bugs, both the traditional species and the redbanded in many fields.
Proper ID is critical or all of these species as concoctions to kill different
species complexes may vary greatly.
Take Home Messages
While a fair amount of our cotton is out of the woods, we
need to keep scouting in later fields and be prepared to take action when
necessary. Be on the lookout for SLWF in areas with past experiences. Scout and
properly ID which insects are in soybeans to make the most economic control
options possible.
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.