I asked Nikolas Clarkson, one of our 2017 Plains Pest Management
Interns, to cover a hot topic for 2017, The implementation of the new cotton
herbicide technologies in West Texas. Nik
and I worked together on this article to keep the facts as facts and share our
impressions from what we have seen from the field so far.
Cotton
producers and those that work closely with them are becoming more familiar with
the new herbicide technologies and herbicides finally labelled for use this
year. It has not been overnight but we
are becoming better aware of how they should best be utilized. Early in the discussion about these new
technologies, there was quite a bit of confusion about these traits and
products, what they actually were, and where they could be used. So, I am going to start off by listing the new
cotton herbicide technologies and the herbicides that go with them.
First off, I will discuss
Enlist. This trait is currently only in
Phytogen cotton varieties. The herbicides
that can be utilized with these traits are Enlist Duo, Enlist, Roundup (all
formulations), Liberty, and all conventionally labeled cotton herbicides. It is a misnomer that this is 2,4-D cotton. While the base chemistry is there and the
cotton would tolerate the old formulations, they are not labeled and the salt
utilized in this formulation is much different which should keep this notorious
class of herbicides for moving much, much closer to target and from escaping unintentionally.
Next, we have Xtend
cotton. For this trait, we can use XtendiMax
with Vapor Grip, and XtendiMax from Monsanto and Engenia from BASF, Roundup
(all formulations), Liberty, and all conventionally labeled cotton herbicides. This trait has also been miss-named by layman
as Dicamba cotton. Much like Enlist
cotton, the Xtend cotton can tolerate the older formulations of this class of
chemistry but these herbicides should be improved on multiple values.
With the improvement
factor of all of these newer herbicides coinciding with the release of these
cotton traits and a conscious fair price setting near the cost of the old
herbicides, I cannot see any reason to use the older herbicide chemistries with
these new traits. Hopefully, no one is
as the labels of these new herbicides really need to be adhered to if we are to
keep the traits registration. It seems
the application of these technologies in cotton is under the EPA’s microscope.
All
of that does seem quite the mouthful. It
has taken almost all summer for me to wrap my head around these technologies,
herbicides, and implications as we scout fields in front of and behind weed
control applications.
In
following these labels, we have had some hard-earned lessons, and some
successes. Drift has been a paramount
concern for everyone in the area this year.
Built into the labels of these new herbicides are some serious restrictions
about nozzle size and pressure to ensure that drift is minimized and won’t make
a significant impact on any neighboring fields.
While there notable are drift incidents around the area, Blayne seems to
feel it may actually be less this year compared to most growing seasons. This is likely due to the fact everyone is
paying closer attention and correcting any mistakes much quicker. What we have noted more of are, as Blayne
calls them, ‘self-inflicted wounds,’ or damage to cotton from contaminated sprayers,
sometimes from custom applications and sometimes from the producers own
sprayer. This seems to be another way
that an all Roundup system in the region has ‘spoiled us’ and that is in tank
cleanout.
Producers need to
know how to properly clean out their spray tank of Enlist Duo, XtendiMax, Engenia,
or any other new herbicides once they are finished using it to prevent from becoming
an issue for the next treated field. It
is not as easy as we have been doing recently.
Each herbicide has some minor but specific and labeled differences in
how tank should be cleaned out. For the
sake of time I am about to going to go with the recommended way on the Enlist
Duo product label. The time to clean out
the tank is right after you are finished using it. Do not wait until the next
day. Triple rinse is a minimum, not a
suggestion with these herbicides.
For the first
rinse, completely drain the system and leave for about 5 minutes and then fill
the tank with water to about 10% of the total tank volume and circulate it
throughout the entire system for 15 minutes and then spray it out the boom. Drain out the system again for 5 minutes and
remove and clean the filters. For the
second rinse fill the tank with water and add the recommended rates of cleaning
agents. Circulate the solution for 20
minutes and then let it stand for a few hours. For the next rinse, drain the whole spray
system again, fill the tank with clean water to 10% of the tank volume and
circulate so that all surfaces are contacted for 15 minutes. Drain the entire
system again and remove nozzle tips and clean them separately.
This is not any ‘fun.’ Blayne makes sure we follow these rough
guidelines for our backpack sprayer and bottles we use for the Plains Pest
Management research plots, so I feel the pain of this extra work. In a zero-tolerance situation, such as a
small plot research trial or an Enlist field about to be sprayed with a sprayer
that has just sprayed Enginia or XtendiMax (or vice-versa), the results are
terrible and impact unpredictable. In
these cases, either a ruined trial or a severely damaged field, which I have
seen a fair amount of this season.
Resources:
Keeling, J.W. Keeling, E.M.
Koonce, A.T. 2015. Weed Management with Engenia In Bollguard II XtendFlex
Cotton. Minneapolis, MN. Entomological Society of America.
Reed, B., 2017. Herbicide Discussions and Intern
Trainings. Plains Pest Management.
Thanks Nik,
Blayne Reed