Calibration of air blast sprayer (ABS) equipment is the best way to ensure spray applications are effective, efficient, and economical. Poor spray coverage is the primary cause of reduced spray product performance. Regular care and maintenance will ensure the sprayer is residue-free and in good operating condition.
The challenge with ABS calibration is accurately and efficiently collecting and comparing nozzle output. As a result, historically, growers “calibrate” their sprayers by filling their spray tanks, making an application, determining how much material remains in the tank, subtracting that amount from the initial amount in the tank, and dividing that by the number of acres covered.
For example, using 100 gallons of application material over one acre leads the applicator to calculate that since 50 gallons of material remains in the tank, the rate of application is 50 gallons per acre. Although this method provides growers with an approximate gallon per acre application rate, it does not give an accurate picture of where on the target crop the material was applied, and if coverage was uniform.
Over the past three years, the Penn State Pesticide Education Program (PEP) has partnered with George Hamilton, Extension Educator at the University of New Hampshire, to develop a calibration program to educate growers regarding the importance of air blast sprayer calibration. In addition, air blast sprayer calibrations were conducted at the grower’s field or farm. To keep up with increased demand, additional technicians were trained in 2012 and 2013 and the PEP purchased two additional calibration units in 2013. Input from surveys indicated that the average price growers would be willing to pay to have their sprayer calibrated was $50.
To show growers the true cost and value of sprayer calibration and encourage adoption, but keep the cost at $50 again this year, the PEP solicited and received a grant from the State Horticultural Association of Pennsylvania. In addition, the Pennsylvania Department of Agriculture provided significant financial support to keep the grower’s cost low. As a result of these efforts, the number of calibrations increased exponentially from the initial pilot test of 10 sprayers in 2011 to over 70 sprayer calibrations in 2013.
After having their sprayers calibrated for the first time, most growers indicated they would be willing to pay more for future calibrations. Every sprayer that was calibrated required some type of adjustment, from minor to significant, to maximize the sprayer application efficiency. By doing precise calibration, one grower estimated that they now mix 10% less material per tank than in the past. Instead of mixing a tank for 5.5A, they have the confidence to mix at 5A per tank. Previously, they always added a 10% “fudge” factor because they were never 100% confident of their old calibration methods. This can mean substantial savings for growers. When a sprayer is calibrated, a worksheet is completed and provided to the grower as a baseline for future calibration and as documentation when required for GAPS or other food safety based certification programs.
Additional information regarding the air blast sprayer calibration or to make a request for a sprayer calibration, growers can access the Pesticide Education Program Air Blast Sprayer
Source:psu.edu