Specialists Speaking- Brian Pieralisi
Brian Pieralisi
MISSISSIPPI
It is a hot one in Mississippi as I write this on Sept. 8, 2026. Believe it or not, today is the first day of a cool spell to hit our state with highs only in the low- to mid-90s! The past two weeks have been brutal here with heat indexes reaching 110 to 117 degree. These temperatures and sunshine have accelerated this crop to maturity in a hurry. Later-planted cotton (May 25-31) went from five nodes above white flower to done flowering faster than I’ve seen in a while.
This brings us to defoliation. Some acres of early planted cotton were defoliated during the last few days of August and first few days of September. Excessive heat made this one a little tricky in some cases. The standard defoliation I recommended was 3 ounces of thidiazuron plus 25 ounces of ethephon per acre. This is straight forward in irrigated or non-drought-stressed cotton. In these circumstances, we would typically add a low rate of tribufos to the above recommendation. However, with the extreme heat indexes and high temperatures, we had to be careful with tribufos. Either going with ultra-low rates, such as 2 ounces per acre or using AMS to help with leathery, drought-stressed foliage.
Most of our defoliation will occur over the next two weeks. The forecast looks more seasonal, and I do not foresee any major issues through the third week in September. I hope the forecast holds true and we can put this crop in the books. In terms of how the crop looks across the state, I think there is potential to pick a good crop this year. I get a little superstitious when trying to forecast how good a crop looks; maybe it is because I am a former cotton farmer. I guess we will wait and see what we find out in the next month or so!
