However, this is not always true, and we often have failures. Thus, defoliation has come to be considered as much art as science. There are many benefits that can be expected from a good defoliation job. Many experiments have shown that defoliation improves picker efficiency in fields with large green plants. Additionally, defoliated fields tend to dry out faster, permit more picking hours per day and allow picking sooner after rain.
Defoliation also cuts off the food supply to late season insects that are entering diapause.
Under certain conditions, defoliation has reduced boll rot by creating better drying conditions in the field. This is especially true in rank cotton. Defoliation may also have some disadvantages and limitations. When plants are defoliated, the fiber and seed development essentially stops. Therefore, if too many bolls are immature at the time of application there can be a reduction in yield and quality associated with the treatment.