Managing Pesticide Drift Mary Beth Henry Aquatic Weed Short Course May 5, 2010, Coral Springs Marriott

Transcription

1 Managing Pesticide Drift Mary Beth Henry Aquatic Weed Short Course May 5, 2010, Coral Springs Marriott

2 Learning Objectives What spray drift is How environmental factors affect drift The effects of droplet size How your decisions can affect spray drift UF/IFAS PIO

3 What is Drift? The physical movement of pesticide through the air at the time of pesticide application or soon thereafter from the target site to any non- or off-target site. Unknown Photo Source

4 What isn t Drift? Pesticides moved by: Erosion Migration Volatility Windblown soil particles Unknown Photo Source

5 Types of Drift Vapor Drift - associated with volatilization, gases, fumes Particle Drift - movement of spray particles Unknown Photo Source

6 Why All the Interest in Drift? Spotty pest control Wasted chemicals Off-target damage Environmental impact Water and Air Quality Public more aware of pesticide concerns Spraying in more populated areas Unknown Photo Source

7 Why All the Interest in Drift? Because drift can cause injury to: Adjoining crops Livestock Wildlife Humans Because drift costs money: Restitution for damaged crops Reduced control of intended target pest(s) Increased regulations because of drift problems

8 Detrimental effects of drift Reduced application rate on target pest Applying pesticides in a manner that allows drift to occur is a label violation

9 Recent EPA Activity a. Draft label changes regarding drift b. Comment period closed 3/5/10 c. 935 submissions 9

10 What are the major factors in managing drift? a. Droplet size b. Wind speed and direction c. Chemical and formulation d. All of the above 10

11 What are the major factors in managing drift? a. Droplet size b. Wind speed and direction c. Chemical and formulation d. All of the above 11

12 Chemical Formulation Additives Drop size Evaporation Factors Affecting Drift Unknown Photo Source

13 Factors Affecting Drift Environmental Factors Wind speed and direction Temperature and humidity Air stability/inversions Topography Unknown Photo Source

14 Factors Affecting Drift Equipment & Application Nozzle type Nozzle size Nozzle orientation Nozzle pressure Height of release Technology UF/IFAS PIO

15 What is the target minimum droplet size to reduce drift: a. 50 μm b. 100 μm c. 200 μm d. 350 μm 15

16 What is the target minimum droplet size to reduce drift: a. 50 μm b. 100 μm c. 200 μm d. 350 μm 16

17 Droplet Size Large droplets have less potential to drift because they: Fall more quickly Evaporate more slowly Are less affected by wind Small droplets often result from: High spray pressure Small nozzle tips Wind shear across the nozzles UF/IFAS PIO

18 Droplet size Droplet diameter is measured in microns (μm) 1 μm = mm = cm Type of droplet Diameter (μm) Smoke <1 Fog 15 Mist 50 Grain of salt 100 Rain 500

19 Comparison of Micron Sizes for Various Items (approximate) 2000 μm 850 μm 420 μm 300 μm 150 μm 100 μm #2 Pencil lead paper clip staple toothbrush bristle sewing thread human hair 150

20 Relationship of Drift to Drop Size Volume Median Diameter (VMD) One micron (μm) =1/25,000 inch Spraying Systems Co.

21 3 mph wind Droplet release: 3 ft. above ground

22 Small droplets Large droplets

23 Droplet size Droplet size is influenced by nozzle orifice size and spray pressure At a given pressure, droplet size decreases as nozzle orifice size decreases At a given nozzle orifice size, droplet size decreases as spray pressure increases

24 Labels and Droplet Size CDMS

25 Droplet spectrum 1 Contact insecticide & fungicide Systemic insecticide & fungicide Contact foliar herbicide Systemic foliar herbicide Soilapplied herbicide Incorporated soilapplied herbicide Very fine (VF) Fine (F) X Medium (M) X X X X Coarse (C) X X X X Very coarse (VC) Extremely coarse (XC) X X X X 1 Based on Volume Mean Diameter (VMD) designation.

26 ASABE Spray Quality Categories Category (symbol) Very fine (VF) Fine (F) Medium (M) Coarse (C) Very coarse (VC) Extremely coarse (XC) Color code Red Orange Yellow Blue Green White

27 Spraying Systems Co.

28 Very fine Increasing orifice size Fine Medium Coarse Very coarse Increasing pressure Extr. coarse

29 Droplet size Use nozzles with the largest orifice size that is appropriate for the application Use a spray pressure near the middle of the range for a given nozzle

30 Low Drift Nozzle Types UF/IFAS PIO

31 Which Size is Best? Western Crop Protection Association

32 Droplet size Nozzle orifice size and spray pressure should maximize droplet size but still provide adequate coverage Droplets too big: Poor coverage Good droplet size: Adequate coverage

33 Weather Wind Factors You Can t Control (speed & direction) Temperature Humidity Susceptible crops or other non-target areas of concern near your application site Western Crop Protection Association

34 UF/IFAS PIO Wind

35 The range of wind speed to avoid drift is: a. 0-3 mph b. 2-5 mph c mph d mph 35

36 The range of wind speed to avoid drift is: a. 0-3 mph b. 2-5 mph c mph d mph 36

37 Wind Drift potential is lowest at wind speeds between 3 and 10 miles per hour Kansas State University

38 Kansas State University Wind

39 Temperature and Humidity The faster they evaporate the more likely they are to reach a driftable size before reaching the target Spraying Systems Co.

40 Evaporation of Droplets Humidity effects on droplet size 70% RH 30% RH Wind

41 Factors Affecting Drift Temperature inversions Radiant cooling of the ground Unknown Photo Source

42 Western Crop Protection Association

43 Drift Potential vs Inversions Western Crop Protection Association

44 Factors the Applicator can Control You can control The selection of the applicator/operator Equipment selection and setup Field conditions The choice of the product UF/IFAS PIO

45 Equipment Selection and Setup UF/IFAS PIO

46 Strategies to Reduce Drift: Equipment Setup Select nozzle to increase drop size Increase flow rates - higher application volumes Use lower pressures Use lower spray (boom) heights Drift reduction nozzles UF/IFAS PIO

47 Strategies to Reduce Drift: Equipment Setup UF/IFAS PIO

48 Strategies to Reduce Drift: Equipment Setup UF/IFAS PIO

49 18 Vertical 100 Horizontal Strategies to Reduce Drift: Equipment Setup Unshielded boom Wil-Rich shield Wind Cones TOTAL AE shield Avg. wind speed

50 Strategies to Reduce Drift: Equipment Setup UF/IFAS PIO

51 Strategies to Reduce Drift: Electrostatic Sprayers Kansas State University

52 Strategies to Reduce Drift: Electrostatic Sprayers Kansas State University

53 Strategies to Reduce Drift: Sensor- Controlled Sprayers UF/IFAS Doc. HS-872

54 Strategies to Reduce Drift: Drift Reduction Additives Polyvinyl Polyacrylamide Linear alkyl epoxide Polymide copolymers UF/IFAS PIO

55 Nozzle type Strategies to Reduce Drift: Drift Reduction Additives Droplet size (micron) Turbo TeeJet 250b 6.2a Turbo FloodJet 261b 5.5a Turbo Air Induction 284a 5.7a XR Flat Fan (40 psi) 240c 8.1b XR Flat Fan (20 psi) 222c 8.0b Visible injury (meters) University of Nebraska

56 Strategies to Reduce Drift: Drift Reduction Additives University of Nebraska

57 Strategies to Reduce Drift: Drift Reduction Additives UF/IFAS PIO

58 Strategies to Reduce Drift: Buffer Zones CDMS

59 Product Selection UF/IFAS PIO

60 Drift and the Law

61 2,4-D MCPA 2,4-DP MCPP MCPB Dicamba Triclopyr Drift and the Law UF/IFAS PIO

62 Drift and the Law UF/IFAS Agronomy

63 Drift and the Law UF/IFAS PIO

64 FDACS-13345

65 FDACS-13345

66 FDACS-13328

67 A major ag insurance company categorized 1996 payouts due to misapplication. What percentage were due to drift?: a. 33% b. 48% c. 17% d. 68% 67

68 A major ag insurance company categorized 1996 payouts due to misapplication. What percentage were due to drift?: a. 33% b. 48% c. 17% d. 68% 68

69 Why All the Interest? Drift Improper tank mix 33% 33% 8% 2% 24% Whoops wrong field! Off label application Application Equipment

70 What percentage of drift incidences may be attributed to applicator judgment?: a. 16% b. 38% c. 50% d. 78% 70

71 What percentage of drift incidences may be attributed to applicator judgment?: a. 16% b. 38% c. 50% d. 78% 71

72 Why All the Interest in Drift? 23% 13% 26% Nozzle Applicator Physical Other 38%

73 Photo/Diagram Credits Many slides from Fred Fishel Pesticide Drift-Keeping it on Target (included slides from) University of Florida/IFAS Florida Depart. of Agriculture and Consumer Services Kansas State University University of Nebraska US EPA CDMS National Coalition on Drift Minimization Spraying Systems Co. Western Crop Protection Association Additional Slides from Brandon Fast Pesticide Drift "University of Florida, Mention of trade names in this presentation is solely for providing specific information. It is not a guarantee or warranty of the products named, and does not signify that they are approved to the exclusion of others of suitable composition. Use pesticides safely. Read and follow directions on the manufacturer s label. Fred Fishel, Ph.D. Department of Agronomy University of Florida/IFAS Copyright 2009 University of Florida

74 Thanks! Mary Beth Henry