ARS | Publication request: Research to Discover Strategies for Spray Delivery Success

Submitted to: OFA Bulletin
Publication Type: Popular Publication
Publication Acceptance Date: December 12, 2009
Publication Date: February 1, 2010
Citation: Derksen, R.C. 2010. Research to Discover Strategies for Spray Delivery Success. OFA Bulletin. 919:3-5.

Technical Abstract: Efficacious application of crop production materials to an ornamental canopy remains a challenge on many fronts. Limitations by crop, formulation, and production environment require producers to understand how to use each device to achieve their production goals. Research conducted by USDA-ARS scientists at the Application Technology Research Unit (ATRU), Wooster, Ohio, is providing growers with a better understanding of the application process. Several current and planned studies are evaluating the fate of spray within ornamental canopies as well as within plants themselves. Studies have revealed that spray quality may be more important in some instances than water volume. Additional ARS research has shown that the popular handgun applications can result in high variability in canopy deposits even if the operator is closely following application guidelines. Reducing variability in deposits not only can help ensure more efficacious applications but also reduce pesticide useage which contributes to higher production costs and risks to the environment. Recent agency trials found that broadcast applications over a mature poinsettia canopy can result in less variability in the amount of pesticide on the underside leaf surfaces compared to handgun applications. Bio-assays showed that those applications with more uniform distribution of material through the poinsettia canopy resulted in better whitefly control. Studies also revealed that handgun applications can be made more effective by reducing droplet size and increasing droplet velocity through increasing the operating pressure. This research is helping provide growers with additional guidance to help them make more informed decisions that will lead to more efficacious, economical, and safer applications.