TIPS FOR MANAGING SPRAY DRIFT

1. Reduce Spray Pressure: Refrain from using pressures which exceed 40 to 45 psi. Higher pressures increase the number of small droplets. A spray pressure of 30 psi is all that is necessary for most spray tips.

2. Increase Spray Volume: As spray volumes are reduced from the customary 15 to 20 GPA down to 5 to 10 GPA the spray droplet size decreases. The problem is accentuated further if the applicator increases the spray pressure to compensate for the smaller spray volume thinking they can “drive” the sprat into the crop canopy. The result is an increase in the number of small droplets, which will either quickly evaporate before reaching the plant or will be carried off by wind as they lack the momentum needed to reach the plant (small droplets take longer to fall then large droplets). Increasing spray pressure should not be used as a substitute for spray volume.

3. Know the Wind Speed and Direction: The greater the wind speed the farther small spray droplets will be carried. Wind speed can vary greatly from one location to another. Take time to check the wind speed and direction relative to sensitive crops at each field.

4. Use Drift & Deposition Additives such as Poly Control 2, Polyan, Poly Dry I’VOD, and Lovert: Research has shown the use of spray drift management additives can reduce spray drift deposits from 50% to 80%. The “user friendliness” of the various drift and deposition aids available in the market vary. They also vary in terms of additional features and benefits they provide. Research has shown that by adding any of above products VMD (mean droplet size) can be increased 300-400 above water alone.

5. Use Nozzles that Produce Large Spray Droplets: Switching from standard flat-fan nozzles to turbulence-chamber or venturi nozzles increase droplet size thereby reducing the amount of drift. Pre-orifice turbulence chamber nozzles absorb energy in the turbulence chamber reducing exit pressure from the nozzle. The turbo flat-fan nozzle design improves spray pattern uniformity and reduces the percentage of drift droplets under a wide range of pressures. Nozzles should be large enough to accommodate spray volumes of 15 to 20 GPA.

6. Aerial Application: Drift can be more of a problem for aerial applicators. Drift additives are a must. Usually at lower rates for special low volume nozzles.