By Amanda Free, Cotton Research Verification Sustainability Coordinator; and Bill Robertson, Cotton Extension Agronomist
Identifying the last effective boll population is essential for making end-of-season management decisions. Cutout is reached when nodes above white flower (NAWF) counts drop below five or when the probability of accumulating sufficient heat units to mature a flower remain in the season. Crop termination guidelines may be keyed on heat units accumulation beyond cutout based on when bolls can be considered safe from insect damage without significantly impacting yield and quality.
The latest heat unit accumulation table can be found here: Heat Unit Accumulation in Multi Counties as of 9-1-2017.