Harvest is largely underway for most of NC and most of our crop has already been defoliated. For the remaining acres yet to be defoliated, action may be needed soon.

There is potential for a frost next Tuesday/Wednesday-Thursday/Friday mornings according to today’s forecast. The likelihood of a frost is more likely in the Piedmont and northern half of NC Coastal Plains with the exception of the far northeastern counties and the Blacklands. These exceptions as well as the southern half of the coastal plains may not experience freezing temperatures. Of course, weather forecasts often can and do change, so the likelihood of a frost could change substantially as we get closer to early next week. Also, in addition to temperatures, wind speed and precipitation influence the likelihood of a frost. Therefore, it is important to observe your local weather forecast frequently and make your decisions appropriately.

Assuming a frost does occur, it is slightly earlier than normal but still within reason. Typically, our first frost date for most of NC cotton growing regions is anywhere from October 20th – November 1st, with rare exceptions occurring both before and after this range. Generally speaking, temperatures decline to the point that it rarely pays to wait on upper immature bolls much past mid October anyway.

Assuming the forecast is accurate and a frost does occur, action should be taken on any remaining acres that have yet to be defoliated. The only real downside to not taking action now would be if a frost does not happen, and it warms up again to continue maturing bolls. Based on the information we have on-hand right now, there aren’t many meaningful heat units to be had beyond this coming weekend in the forecast for at least two weeks. By then, we’ll be into a November when we can expect cooler weather, additional frosts, and noticeable slowing of drying time (dew and rain) and reduced effective harvest hours.

So what action should you take, assuming a frost occurs in your area?
If you have fields that have yet to be defoliated, especially fields with unopened bolls, you should defoliate sometime this weekend using a high rate of Ethephon or more active forms of ethephon such as Finish/Terminate (generally 1 quart/A….can add 10 oz of regular ethephon, such as Prep/SuperBoll/etc for enhanced boll opening) or CottonQuik/FirstPick (generally 2 quarts/A). Add 6.4-8oz/A of Ginstar/Adios/CutOut to Finish/Terminate (not to CottonQuik/FirstPick) to properly address regrowth and overall defoliation. Due to cooler temperatures, Dropp/Freefall activity will be slower and reduced, hence the recommendation to replace it with a Ginstar/Adios/CutOut product, which will remove/prevent regrowth as well as remove older leaves. Folex may still be suitable for removing older leaves but won’t do much for regrowth. If there are no signs of regrowth and you intend on harvesting quickly, Folex can be added to Finish/Terminate instead of Ginstar/Adios/CutOut. Most fields however do have some degree of regrowth. Therefore, a tankmix of Finish/Terminate plus Ginstar/Adios/CutOut does not need the addition of Folex or Dropp/Freefall.

It is important to take action 3-4 days ahead of a frost, assuming one occurs, and preferably on a warm and sunny day without the likelihood of rainfall. This will improve the odds of unopened bolls cracking and opening after a frost vs rotting. This is all dependent on maturity of closed bolls so there is no guarantee. Luckily for this year, there aren’t many ultra-late planted fields nor is there much of a real immature top crop worth chasing in most places

If you have fields that have already been defoliated, with nearly all leaves removed, but still has some closed bolls that haven’t opened, paraquat at 8 oz/A (if using 3-lb material) to 12 oz/A (if using 2-lb material) can sometimes drastically improve boll opening. This should NOT be done as a first attempt at defoliation, but rather, only as a second application if a number of bolls won’t open otherwise and if all leaves have already been removed. The success of this approach is also dependent on boll maturity, therefore it can be unpredictable at times. Per the label, you must wait 3 days to harvest, but it wouldn’t be advised to wait much longer than 5-7 days, as this product is a desiccant. The longer you wait to harvest, the likelihood of quality deductions for bark and trash increases.