Abstract
A Buffalo Turbine barrier treatment sprayer was characterized physically and biologically over a range of application settings. The effects of three increasing droplet size distributions, two air blast strengths, and three blower arm angles (65°, 80°, and 90°) were measured via water sensitive papers and residual contact bioassay. The data from the water sensitive papers provided information on how machine setting influenced the deposition through the canopy. For the canopy under investigation, directing the spray straight into the canopy (90° blower angle) led to the highest deposit volumes. As droplet size distributions increased no significant change in the volume deposited was observed. The increase in air blast strength from low to high had no overall effect on the volume deposited, but the low air blast strength did show a successive loss in volume with distance into the canopy. Whereas the high air blast strength only showed a loss in volume at the furthest distance from the sprayer. Mosquito mortality did not correlate with volume deposited. Mosquito mortality was greatest with the intermediate blower arm angle (80°). The only parameter that correlated with mortality was uniformity of deposits over surfaces. It is suggested from both quantitative and qualitative observations that uniformity was the primary deposition parameter affecting control. The methods set forth in this study are simple and inexpensive our aim is to introduce them a standard methods for optimizing barrier treatment applications for vegetative barrier treatments.