Lucas Pitre
Direct Agronomics LLC
Ville Platte, La.
After several years of working for a consulting firm, this past year I had the opportunity to start my own agricultural consulting business. Throughout the year, I have learned the importance of details. Having information organized in an easy-to-access manner and planning efficient travel routes have proven to save significant time and effort, allowing me to provide better service to clients. This year’s cotton crop is now moving towards its final step – defoliation. Let us keep in mind the details to make the most of the process.
A successful defoliation program can benefit a grower by reducing lint staining and trash in seed cotton and increasing picker efficiency. Several techniques have proven to be effective through the years when determining defoliation timing. Percent open bolls, nodes above cracked boll and accumulated heat units after cutout can be used alone or in conjunction with each other. Each method has advantages and disadvantages and should be followed with a visible inspection to determine which unopened bolls are mature and expected to be harvested.
Once timing is determined, how to defoliate is the question. The driving factors in selection of a harvest aid are environmental and crop conditions. Knowing current conditions and what has worked in the past will help to decide the proper chemical, rate and whether a one- or two-step defoliation program is appropriate. A successful one-pass defoliation program can be effectively implemented when the crop has significant leaf loss and low amounts of green material are present in the crop canopy. A two-step program benefits lush cotton with high amounts of green 
material. Using two applications at lower rates reduces the risk of sticking leaves, limits juvenile growth and sometimes allows for a few more bolls to open.
When applying harvest aids, remember that adequate coverage is key. Use sufficient carrier volume and proper spray tips to ensure thorough coverage to reduce the likelihood of an unplanned additional application. Louisiana Extension defines optimal carrier volume as 15 GPA; using less than 10 GPA is not recommended.
Once defoliation applications begin, only defoliate the amount of acres that can be harvested in a timely fashion. Prolonged lint exposure to weather can reduce grade and yield. Regrowth can become a factor with delayed harvest, costing additional applications or a reduction in grade. Research has shown that 20 percent green leaf material can cause substantial discounts. State Extension services offer defoliation guides listing harvest aid rates and combinations. These guides are very helpful tools to reference when deciding on a defoliation program.
It is easy to be distracted this time of year. The opening of big, white, showy cotton bolls can be blinding. Along with Friday night football games and fast-paced dove shoots, let us not forget to pay attention to details.
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