Effects of Water Hardness on Spray Droplet Size Under Aerial Application Conditions
Abstract
Minerals and organic matter in spray carrier water can reduce the effectiveness of some plant protection products. Water hardness has been found to have a significant impact of the efficacy of some crop protection materials and has shown conflicting influence on spray droplet size. The objectives of this study were to determine the effects of water hardness on spray droplet size produced by two commonly-used aerial spray nozzles with and without the addition of an invert suspension adjuvant to the tank solution under aerial application conditions. Water hardness levels from 0 to 800 ppm and/or the addition of a spray adjuvant to a spray solution had a significant effect on spray droplet size. The spray adjuvant, an invert suspension, increased most spray droplet size parameters and decreased the percent of spray volume contained in droplets less than 200 micrometre as long as the water hardness did not exceed 200 ppm. The spray adjuvant had little effect on relative span when the spray was released at a 45 deg angle to the high speed airstream, but lowered the relative span for sprays orientated 0 deg or straight back relative to the high speed airstream. Aerial applicators should test the water used in making tank solution for water hardness before the addition of spray adjuvants.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 2008
- Accession Number
- ADA495022
Entities
People
- Bradley K. Fritz
- Daniel E. Martin
- Wesley C. Hoffmann
- William E. Bagley
- Yubin Lan
Organizations
- Agricultural Research Service