Nozzle positions – On or off?

Adjusting the nozzles on a fishtail-style nursery sprayer.

Spray that is not directed at the target is wasted spray. Many pesticide labels specifically require the operator to restrict spray to the target canopy. Spray that escapes above the canopy is a significant source of off-target drift. Foliar applications that extend below the canopy are not efficacious and represent waste and lost productivity. Air […]

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How to use Airblast Nozzle Tables

The author looking up nozzle rates during a spring calibration. The operator was running at 190 psi, but the catalogue only listed 180 psi and 200 psi. When span is only 20 psi, it’s fairly safe to approximate the output. When the table only lists in 50 psi increments, it is more difficult to determine the rate without testing the output. This issue usually occurs at pressures above 200 psi, and that’s very high for most horticultural operations. Consider using a lower operating pressure, if possible.

Airblast operators should know how to read a nozzle table. They are found on dealer and manufacturer websites as well as in their catalogs. Table layout varies with brand, but they all relate a nozzle’s flow rate to operating pressure. The better tables also provide the spray angle and the median droplet size (i.e. spray […]

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Airblast maintenance inspection – the morning walkaround

Adjusting the nozzles on a fishtail-style nursery sprayer.

An airblast sprayer inspection is part of preventative maintenance. This daily activity identifies small problems before they become big ones. You can do it at the filling station, so it’s fairly convenient. Don’t think of it as stealing time from your spray day… it’s part of your spray day. Don’t skip it. If time is […]

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Airblast calibration – clearing up confusion

Here are some nasty disc & cores revealed during a calibration workshop. It certainly explained the poor performance the operator was complaining about. Is it time to replace yours? Photo credit – Dr. H. Zhu, Ohio.

“Sprayer calibration is an important part of any crop protection program.” Everyone says so, so it must be important. But what exactly are they asking you to do, and why? When delivering presentations I often take the opportunity to ask audiences to define airblast sprayer calibration. Their responses cover a wide range of activities that […]

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Cleaning an airblast sprayer

Next to sprayer math, cleaning the sprayer is one of the more distasteful aspects of airblast spraying. It’s time-consuming, you never really know when you’re finished, and sprayer manufacturers and pesticide labels offer only limited guidance. Clean sprayer rinsate often looks and smells exactly like contaminated sprayer rinsate. When airblast sprayers are not cleaned as […]

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