Observations, Thoughts And Expectations
DR. TYSON RAPER
JACKSON, TENNESSEE
I’ve spent several days over the past week making my way through much of Tennessee’s cotton. In this blog, I share a few observations, several thoughts on where we are, and attempt to set expectations for the 2025 crop.
In the past week, I’ve attempted to do a relatively large circle through West Tennessee and chat with individuals in areas that I’ve been unable to see. Attempting to summarize observations across such a large area will surely, every time, fail to describe portions of the crop, especially when rainfall is as sporadic as it has been through July.
White flowers in the top of the canopy are easy to see from the road in much of our dryland crop. That applies to all but our latest planted acres and to the acres that received a considerable amount of rainfall two weeks ago. That event, much like the event this past Friday (8/8), was patchy. Retention has been good to very good. Our early crop has loaded nicely. All that separates this early crop from at- or above-average yields is a couple rainfall events between now and early September.
My concern with our later planted acres is growing. The frequent and substantial rainfall events that most received in May, June and the beginning of July did not prepare the plant for periods of even slight drought stress. I’m a strong believer in preconditioning cotton for drought by allowing it to experience some water deficit stress early in its life; my ideal cotton year would consist of a relatively dry May and June, followed by only adequate rainfall through July and August. The experience of slight drought stress early in a plant’s life allows it to better handle even moderate drought stress later in the season, should it occur. In contrast, our relatively shallow-rooted crop is not remotely prepared for the dealt hand.
Node Above White Flower (NAWF) counts in our later planted acres are crashing. Many of these acres began blooming 10-14 days after the fourth of July. Several have commented that the heat we experienced in July ‘sped up our later-planted crop’- and while I would agree with that observation, I believe the heat coupled with the current drought stress hurt us, not helped us. You can see the shift in heat unit accumulation which occurred in late June and early July; while we are still behind 2022, 2025 quickly deviated from the 2023 pattern and 2025 has almost caught 2024.
It has been several months since I last spoke with Dr. Bill Robertson, so I gave him a ring late last week to discuss my concerns with this crop and rehash a concept we discussed at length several years back. Dr. Robertson was involved with the development of the COTMAN system and I’ve visited with him several times about the old Target Development Curve (TDC) in relation to what we are observing now. Although we traditionally have called NAWF 5 cutout and expect to see NAWF counts decline quickly after that point, we now often observe NAWF to hold steady at 5 across even weeks of time, with a much more gradual decrease in NAWF when the plant finally does begin to close the distance between the flowering node and terminal. In my opinion, the ability of our current germplasm to ‘ride’ NAWF 5 for a substantial period of time is one of the main reasons we have seen yields increase year after year.
In 2025, our late planted dryland acres blew past NAWF 5, at a rate much faster than we’ve observed in the past ten years. Our effective flowering window on our late crop appears to be closing very quickly, after just opening.
USDA estimated our planting acreage in June at 260,000. I was at 150,000. They’ve updated their number with FSA data today to 190,000. USDA is estimating our yield per acre to be 1,061 lb. I’ve peeled back quite a few canopies to find fewer and smaller bolls than I’d prefer, but as Gillian Welch sings, ‘time’s the revelator’. I sure hope they are right, much as I had wished their acreage number was right- but my yield number is notably lower. That said, Dr. Robertson wisely restated as we wrapped up our conversation, ‘with cotton, it is usually not as bad as it seems’.
So what is there to do?
Recognize the end of the effective flowering window is upon a few of us- and past most of us. If I’m within 300 heat units after NAWF 5, I’m fending plant bugs off with fury and keeping an eye on stink bugs, but after that mark, I’m cutting them loose- far earlier than normal.
A shot of mepiquat on acres that receive rainfall may slow down the development of a switch, but it will not prevent a large flush of juvenile growth by the time we look to defoliate. We have a considerable amount of fertilizer under much of this crop that hasn’t been used. If we happen to see an area wide rainfall, particularly if a named storm finds its way up the Mississippi, this will be a two shot defoliation. Cuticles are thick and tough; even if we get temperatures for thidiazuron, tribufos will also be in my first shot. ∆
DR. TYSON RAPER
UNIVERSITY OF TENNESSEE