Cotton planting has begun across the state of Alabama as of this week. Overall, we are SEVERELY limited by moisture, but planters have begun, nonetheless. Currently, the next good chances for rain (according to James Spann) are not until April 24-26. If I felt good about soil moisture, I think I too would start planting cotton as soon as I could. If we consider the disaster most of May was for trying to get seed in the ground. Planting dates are always a gamble, but I would consider planting as soon as you can.
Moving into the current insect situation, things have (thankfully)
been quite so far. We have found no cotton jassid activity on sticky card traps
or on February – March planted cotton in Headland. We have, however, heard a
few reports of grasshoppers in fields that will soon be planted. I suspect the
dry weather we have experienced will be favorable for grasshoppers this spring.
For developing populations of immature grasshoppers (which do not have wings),
Dimilin (2 oz) is a good option that provides residual control. We do not
expect any adults (which do have wings) in fields currently. Thus, I would
leave out additional “knockdown” insecticides for now.
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| ThryvOn and Non-ThryvOn cotton planted in the same row. |
One pest that the dry weather seems to absolutely be impacting is thrips. According to the Thrips Infestation Predictor Model for Cotton (Thrips Model), we are expecting EXTREMELY high pressure this year. Regardless of location in the state, the model is predicting that the 3 weeks between April 20 and about May 12 will experience the majority of the issues. Keep in mind the model prediction is based on weather, so things can change. Running the model before, during, and (a few days) after planting will give the most up-to-date information.
I suspect that the majority of this cotton will need something
to supplement seed treatments this year. Depending on how you are set up, you
may or may not be able to us in-furrow applications.
If you are unable to make in-furrow applications, using ThryvOn
varieties is an easy way to get excellent thrips control. To date, we have NOT
observed thrips damage in cotton that justified an in-furrow or foliar
application.
Another option would be to make foliar insecticide applications.
Current recommended options include:
Hemi SC (1.5-3.0 oz) This product has a 2ee label to provide
early season suppression of thrips in cotton. For heavier infestations, use a
higher rate in the rate range. (low risk to flare spider mites)
Acephate (3 oz) is an effective and relatively
inexpensive option, however it has the potential to flare secondary pests such
as spider mites and is the least rainfast of the recommended options available.
Bidrin (3.2 oz/A) is another option that is
effective and less likely to flare spider mites and is more rainfast than
acephate, however it is more likely to cause crop injury when tank-mixed with
herbicides.
The general goal of thrips management is to get cotton to about
the 5th or 6th true leaf stage without too much injury
from thrips. In most years, many acres do not need foliar applications in
addition to at-plant insecticides to reach this goal. However, some fields do.
Rarely do fields in Alabama need more than 1 foliar spray for thrips. This year,
however, could be a rare year. With the current thrips model predicting such
heavy pressure, one application may or may not do it. Much of this will depend
on weather factors and how quickly the cotton can get from the cotyledon stage
to 5 or 6 true leaves. We will know a lot more on June 1st about
what happened than we do now. But for the time being, I would be prepared to
think about the potential of multiple trips for thrips in non-ThryvOn cotton
and cotton without AgLogic.
As always, if we can ever be of any help, or if you would
like to provide input on the situation in your area, please don’t hesitate to
reach out to your local Extension Agent or myself (Scott Graham: 662-809-3368)
and Ron Smith (334-332-9501). For more information on thresholds and
insecticide recommendations, visit the Alabama Cotton IPM Guide (IPM-0415). To stay up-to-date on the Alabama cotton insect situation,
subscribe to the Alabama Cotton Shorts Newsletter,
Alabama Crops Report Newsletter and Podcast,
and the Syngenta Pest Patrol Hotline.
