As we roll into and quickly through August, I usually cycle this topic back to the top with any updates as the time for making the desiccation decision is quickly approaching. With all of the early-soybean acres planted in 2026, desiccation calls have come a litter sooner this year as well.

With few exceptions, Tennessee is about to harvest a fantastic soybean crop. While harvest aids do not increase grain yield, they can still add value in several ways. A well-timed harvest aid application will usually put a combine in the field sooner than allowing the plants to senesce n on their own. Desiccating beans also increases harvest efficiency and decreases potential environmental impacts from inclement weather conditions during this part of the season.

I frequently use Sharpen, Defol 5, and Gramoxone each year in various trials and situations. They all can and do work well in certain scenarios. However, if I had to pick just one to cover all plant and environmental conditions, it continues to be Gramoxone. Defol 5 works well, but it’s speed of advance (efficacy) can be sensitive to variable environmental conditions. Sharpen also does a good job if partial defoliation has already occurred.

TIMING!! Application timing is always way more important than which product you choose.

• You will incur a yield penalty (up to 15%) if you desiccate at R6.
• 5 (physiological maturity) is the earliest time that applications should ever be made.
• UT Recommendation: R7 – 1 healthy pod on the mainstem has reached its mature brown color.

You may successfully apply harvest aids at R6.5 if soybean growth stage is uniform across the field. However, this is not a normal occurrence in Tennessee.

Delaying your targeted application timing until R7 helps ensure that all of your field has at least reached R6.5.