CONTRIBUTION OF MULTIPLE PASSES TO DOWNWIND MOVEMENT OF SPRAYS

By

W. Clint Hoffmann, Daniel E. Martin, and Bradley K. Fritz

Contact: Dr. Clint Hoffmann, Agricultural Engineer, USDA-ARS, 2771 F&B Road, College Station, TX 77845 email: choffmann@tamu.edu

Abstract. Aerial applicators and researchers understand that the spray pass with the highest probability off-target movement is generally the downwind pass on the field edge. The research presented in this paper is designed to measure and quantify the individual contributions of upwind spray passes to the level of spray material that moves downwind over a crop canopy and bare ground. This research project demonstrates a new sampling scheme for measuring individual spray passes and the overall downwind movement of sprays from an agricultural aircraft. The two different application setups used in this study had very different levels of airborne spray at two distances from the application site. The research also indicated that once the aircraft is 3-4 passes upwind, there is little additional contribution to the downwind movement of sprays past the sampling stations used in this study.

<Select to See the Presentation>

Note:  A copy of the manuscript for this paper is not available at this time.  Please email the author to receive a copy.  choffmann@tamu.edu