Drift

1. Drift

2. 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)

3. Misapplication Facts Source: Farmland Insurance 1996

4. Contributions to Drift

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

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

7. Reducing Pesticide Drift Nozzles, Nozzles and More Nozzles!!

8. Low Drift Nozzles • 87% reduction in drift prone droplets • < 150 microns • Low drift nozzle @ 0.2 gal/min flow rate - 40 psi • Compared to 8002 Standard Flat-fan nozzle

9. 8003 tip 80 means 80o fan 03 means 0.3 gallons per minute at 40 psi(38 ½ ounces per minute)

10. 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

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

12. 2000 m 850 m 420 m 300 m 150 m 100 m #2 Pencil lead paper clip staple toothbrush bristle sewing thread human hair Comparison of Micron Sizes(approximate)

14. Driftability of Spray Droplets of Varying Sizes Crosswind @ 3 mph • 20 m • 50 m • 100 m • 150 m • m • 8 ft 22 ft. 48 ft. 178 ft. 1065 ft. 10 feet \

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

16. Tip Spray Selection by Drop Size Turbo TeeJet Flat-fan

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

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

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

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

21. Hypro Ultra Low Drift • 15 – 100 psi range • 120o pattern • $4.00 - $5.00 • Fits Standard fan tip caps

22. Spraying Systems DG TeeJet • Removable Pre-orifice • $4.50 - $5.00

23. Turbo Tee Jet • 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

24. Turbo Flood Nozzles • Spraying Systems • Clog resistant • Wide angle

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

26. 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

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

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

31. Weather and Other Factors Affecting Drift • Temperature & humidity • Air movement (direction and velocity) • Air stability/inversions • Topography

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

33. Evaporation and Deceleration of Various Size Droplets* Droplet Terminal Final Drop Time to Deceleration Diameter Velocity diameter evaporate distance (microns) (ft/sec) (microns) (sec) (in) 20 .04 7 0.3 <1 50 .25 17 1.8 3 100 .91 33 7 9 150 1.7 50 16 16 200 2.4 67 29 25 *Conditions assumed: 90 F, 36% R.H., 25 psi., 3.75% pesticide solution

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

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

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

38. Shielded Sprayers

39. Shrouded Sprayers