Preparing for Defoliation​

July 2020 | 27 min., 47 sec.
by Steve M. Brown
Auburn University


​​This presentation addresses principles and considerations for defoliant and harvest aid use in cotton. Although preparations for harvest are quite diverse across the U.S. Cotton Belt, this presentation outlines the overall purpose and specific functions of these tools, as well as the modes of action of the two primary groups of products: herbicidal and hormonal. Several methods can be used to know when to make applications, and one method is a singularly good tool to confirm timing decisions. Specific “recipes” are not provided (practices are too different across growing regions), but discussion includes how to think about crop conditions, weather trends and threats, retreatment, the calendar, and other factors. A few points are made about minimizing problems with extraneous matter penalties in the classing system.​​​​

About the Presenter

​​Steve M. BrownSteve M. Brown is a 1978 graduate in agronomy and soils from Auburn University and later earned MS and PhD degrees in agronomy/weed science at Auburn and Texas A&M, respectively. He worked as an assistant county agent in a cotton pest management role for a couple of years in northern Alabama and then served as a research associate in a Cotton Incorporated-funded project on no-till cotton from 1980 to 1984. From 1987 until 2008, he served as an Extension weed scientist and cotton agronomist for the University of Georgia in Tifton. He worked for a major seed and biotechnology company from 2008 until 2019, when he joined the faculty at Auburn. His entire career has focused on cotton.

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