Defoliation is the application of chemicals to encourage or force cotton leaves to drop from the plant in order to harvest the crop in a timely manner. Defoliation is a balancing act between killing the leaves and not affecting the leaf. For successful defoliation, the leaf must stay alive long enough to begin the formation of an abscission zone that results in leaf drop. If the leaf is killed too rapidly, the chemical signals are not sent from the leaf to the abscission zone. The result is a leaf that is frozen or “stuck” to the plant, creating unnecessary trash. Proper defoliation is a profitable part of a total cotton management system.
1. Elimination of the main source of stain and trash, resulting in better grades.
2. Faster and more efficient picker operation.
3. Quicker drying of dew, allowing picking to begin earlier in the day.
4. Straightening of lodged plants for more efficient picking.
5. Retardation of boll rot.
6. Potential stimulation of boll opening, which can increase earliness, yield, and profit.
NC Coorporative Extension