|
|
|
Posted 20 June 2008. Crop Management. Guarding Against Pesticide Drift South Dakota State University. www3.sdstate.edu Brookings, South Dakota (June 6, 2008)--Pesticide drift is becoming a concern in South Dakota this year as recent wet conditions in some areas have put pressure on producers to get fields sprayed.
“Many pesticide applicators find themselves pressed to make applications in marginal spraying conditions. I have seen recent applications where the spray was visibly moving off of the field. This represents two problems. If the spray isn’t going on the field, it could decrease the effectiveness of the application. More importantly, from a monetary standpoint, pesticide drift may cause injury to nearby areas resulting in fines or lawsuits,” SDSU Extension Pesticide Education Coordinator Jim Wilson said. Wilson said applicators can do better at keeping pesticides on the field by managing the droplet size produced by the sprayer nozzles. “Droplets that are about the diameter of one and one-half human hairs or smaller are most prone to drift from the field,” Wilson said. “With many pre-emergence and systemic herbicides, quite coarse droplets can be used without sacrificing effectiveness. With conventional nozzles, dropping boom pressure or moving to larger-sized nozzles will increase droplet size and decrease driftable droplets.” Producers should consult nozzle literature to determine what changes are necessary to move to a larger droplet size category. Numerous brands of air induction nozzles are also available that will help reduce drift from the field. Wilson added that sprayer booms are often set much higher that recommended. This allows the wind additional opportunity to catch small spray droplets and move them from the field. SDSU Extension Fact Sheet 919, “Choosing drift-reducing nozzles,” summarizes drift management techniques and offers a description of air induction nozzles. The publication is out of print but available online at: agbiopubs.sdstate.edu/articles. SDSU Extension Climatologist Dennis Todey said producers can use an SDSU Climatology Web site to track wind speed and other weather conditions when deciding whether to spray. Find it from the main SDSU Climatology Web site, climate.sdstate.edu. Click on “Recent automatic stations’ data.” The SDSU Climatology Web site has directions for finding additional wind and forecast information from the National Weather Service. Wilson added that producers should evaluate the areas around the field to identify ‘sensitive’ areas when even more care is required. Fields near towns, schools, plant nurseries, and certified organic fields are examples of locations where an even higher level of care is required. Contact: |
