Equipment II Nozzles Nozzles Selection Low Drift Nozzles

Swath Width

Nozzles Regulate Flow (GPM) Atomize liquid into droplets Pattern Nozzle Materials BrassPlastic Stainless Steel Ceramic Tungsten carbide Aluminum

Floodjet

Even Flat Fan

Broadjets/Boombusters Boominators

Tapered Flat Fan o fan psi 0.3 GPM = ? ounces 38.4 ounces

Nozzle selection page 86 GPA x MPH x W 5940 GPM = 30 GPA X 5 MPH X 20” GPM =

Drift

Why Interest in Drift? Spotty Pest Control Wasted chemicals Off-target damage Higher costs - $$$ Environmental impact –Water and Air Quality Public more aware of pesticide concerns! (Negative) Spraying in more populated areas? (Suburbs)

Source: Farmland Insurance 1996

WHAT IS DRIFT? Movement of.. spray particles vapors off-target Less effective control Possible injury to susceptible vegetation and wildlife.

Spray Characteristics Affecting Drift Chemical Properties Formulation Evaporation Drop size Volume Equipment & Application Factors Affecting Drift - Nozzle type –Nozzle size –Nozzle orientation –Nozzle pressure –Height of release

87% reduction in drift prone droplets < 150 microns Low Drift Nozzles

Larger droplets At the same flow rate Same operating pressure than standard flat- fan (SFF) nozzles. PRE-ORIFICE REDUCES LIQUID VELOCITY Reduces small droplets (200 microns) by 50 to 80 percent

Drift Potential is Influenced by: Droplet Spectrum (Range - big to small)

Comparison of Micron Sizes (approximate) 2000  m 850  m 420  m 300  m 150  m 100  m #2 Pencil lead paper clip staple toothbrush bristle sewing thread human hair

Driftability of Spray Droplets of Varying Sizes 10 feet 3 mph 20  20  50  50  100  150   8 ft 22 ft. 48 ft. 178 ft ft. 8 ft 22 ft. 48 ft. 178 ft ft. \

Nozzle Drop Size Classes Very Fine to Fine < 200 um Medium to Coarse – 200 to 450 um Very Coarse > 450 um

Tip Spray Selection by Drop Size Turbo TeeJet Flat-fan

Secondary Break-Up Droplet elongation and fracture produces small droplets \

Sources of Spray Mist or Fines Secondary Break-Up Secondary Break-Up Droplet elongation and fracture produces small droplets Droplet elongation and fracture produces small droplets \

Sources of Spray Mist or Fines Aerodynamic Effects Aerodynamic Effects Air friction due to speed of the application vehicle causes additional production of small droplets

Sources of Spray Mist or Fines Aerodynamic Effects Aerodynamic Effects Air friction due to speed of the application vehicle is dependent upon the nozzle orientation angle. 90 o produces the greatest number of small droplets Movement

Hypro Ultra Low Drift 15 – 100 psi range 120 o pattern $ $5.00 Fits Standard fan tip caps

Spraying Systems DG TeeJet Removable Pre-orifice $ $5.00

Spraying Systems Flat Fan pattern wider range of pressures 15 to 90 psi produce fewer drift-prone droplets compared to SFF. Fits standard TeeJet Nozzle caps Turbo Tee Jet

Turbo Flood Nozzles Spraying Systems Clog resistant Wide angle

Conventional SSF Turbo Tee Jet 25 psi at 30” spacings. 20” height

Turbo Drop Nozzle Greenleaf Technologies Air Induction (AI) Venturi pressure reduction chamber Droplets are filled with air and expand when leaving tip Better coverage $10.00

Tee Jet Air Induction TeeJet Banding Tip $7 - $8.00 $6.00 Operates at higher psi to work efficiently Needs special caps

CP Nozzle Dial-an-orifice Pattern similar to flood jet Mainly used by aerial sprayers

äTemperature & humidity ä Air movement (direction and velocity) äAir stability/inversions äTopography Weather and Other Factors Affecting Drift

Evaporation of Droplets Wind High Relative Humidity Low Temperature Low Relative Humidity High Temperature Fall Distance

Evaporation and Deceleration of Various Size Droplets* Droplet Diameter (microns) Terminal Velocity (ft/sec) Final Drop diameter (microns) Time to evaporate (sec) Deceleration distance (in) < *Conditions assumed: 90 F, 36% R.H., 25 psi., 3.75% pesticide solution

Strategies to Reduce Drift Avoid adverse weather conditions Consider using buffer zones Consider using new technologies: –drift reduction nozzles –drift reduction additives –shields, electrostatics, air-assist Increase drop size Increase flow rates - higher application volumes Use lower pressures Use lower spray (boom) heights

Polymer Drift Supressants produce larger droplets across the spectrum, but will decrease the fan angle. Nozzles on the Left have the polymer supressant. Adjuvant Influence on Spray Pattern (Note Fan Angle)

LI 700 R-11 Tallow Amine Water Adjuvant Influence on Spray Pattern (Note Uniformity of Pattern) Source: FRI New Zealand

Shielded Sprayers

Shrouded Sprayers