I’ve had a request to do a running total of DD60 accumulations beginning August 15th. As much of our crop did not reach cutout (NAWF=5) by August 15th, this becomes our default last effective bloom date based on the average historical date of first frost for West Tennessee. Most insecticide applications should be terminated once we have accumulated 350 DD60s from August 15th, and in reality, we should relax our treatment threshold once we have accumulated 250 DD60s.
Like the moth trapping data, you can access the DD60 accumulations at anytime on the Quick Links menu (below left). These calculations are based on weather data for Jackson. Please see www.cottonheatunits.com for weather data from other locations in Tennessee and accumulated heat units. I’ve also included predicted DD60 accumulations using the extended forecast. The forecast predicts that we will accumulate approximately 230 DD60s by August 28th. I will update this information several times a week.