Pesticide Drift MSU Pesticide Education Program Michigan Groundwater Stewardship Program (MGSP) Note to presenter: It is highly recommended to use one or more of the three versions of the generic pesticide drift management plan as handouts (available at web site). Applicators should be encouraged to customize the generic plan to their farm for use at application time The Farm Bureau/Craig Andersen version also provides a copy of, Reg 637 Part 10,

Pesticide Drift MSU Pesticide Education Program Michigan Groundwater Stewardship Program (MGSP)

What is pesticide drift? The physical movement of pesticides through the air at the time of pesticide application, or soon thereafter from the target site to any non- or off- target site. Pesticide drift shall not include movement of pesticides to non- or off-target sites caused by erosion, migration, volatility or windblown soil particles that occurs after application, unless specifically addressed on the pesticide product label with respect to drift control requirements. National Coalition on Drift Minimization

Pesticide Drift Defined Michigan Department of Agriculture –The physical movement of a pesticide at the time of application from the site of application to any non-target site. –Does not include movement by erosion, volatilization or windblown soil particles after the application of a pesticide. Regulation 637, Part of Act 451

Pesticide drift does NOT include Erosion Volatilization Windblown soil particles

This is Pesticide Drift Intended Target Area Drift

Types of Drift Vapor Drift Volatilization or evaporation of pesticide from crop or soil that occurs after application. Particle or Physical Movement of spray particles during or after the application.

Why should you be concerned about pesticide drift? Poor pest control Waste pesticides Public awareness Air and water quality $$$ - higher costs Non-target damage, crops or landscape Neighbor relations

Factors Affecting Drift Spray characteristics –Chemical –Formulation –Additives –Drop size –Evaporation

More Factors Affecting Drift Equipment and Application –Nozzle type –Nozzle size –Nozzle orientation –Nozzle pressure –Boom height Air-assist sprayers Turbo flat fan

Still More Factors Weather –Air movement –Temperature and humidity –Inversions –Topography

Temperature and Humidity Temperature affects –Rate of evaporation of spray droplets –Wind Humidity affects - Rate of evaporation of spray droplets. - The higher the humidity, the slower the evaporation rate.

Temperature and Humidity Droplet Evaporation Low relative humidity high temperature High relative humidity low temperature wind

Weather – Wind Speed and Direction Sensitive areas – buffer zones Don’t spray if wind is blowing toward sensitive area. Not recommended to spray in “dead calm” condition if volatilization is an issue. –Light winds (0-2 mph) unpredictable and vary directions. –Calm and low wind conditions may indicate an inversion layer.

Inversion Layer

Wind Measure wind speed before application 1 mph = 88ft./minute, about 35, 30” rows 10 mph = 880ft./minute, 2/3 across a 40 acre field Wind currents can affect droplet deposition Adapted from Survey of Climatologic: Griffiths and Driscoll, Texas A&M University, 1982 Diagram of wind around a building. Adapted from Farm Structures* * H.J. Barre and L.L. Sammet, Farm Structures (Wiley, 1959) Ground

So, at what wind speed is it appropriate to spray? Calm 0- mph if volatilization is not an issue 2-5 mph ideal - gentle but steady breeze - blowing in a safe direction 5-10 mph with precautions

Droplet Size Smaller droplets are more likely to drift. Measured in microns – 1 micron (  m) = 1/25,000 inch 100  m – human hair 300  m – toothbrush bristle 850  m – paper clip 2000  m - #2 pencil lead For most applications, greater than 150 microns is best.

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

Cutting Droplet Size in Half Results in Eight Times the Number of Droplets 500 Microns 500 Microns 250 Microns 250 Microns 250 Microns 250 Microns 250 Microns 250 Microns 250 Microns 250 Microns 250 Microns 250 Microns 250 Microns 250 Microns 250 Microns 250 Microns 250 Microns 250 Microns

Nozzle Selection Designed to reduce drift and improve droplet size control.

Selecting the Proper Nozzle Legal issues!! Following the label!

Nozzle Dropsize Classification Selection based on droplet size: Very Fine Fine Medium Coarse Very Coarse <119  m  m  m  m >464  m Insecticides and Fungicides Herbicides and Postemergence Soil Applications of Herbicides

Nozzle Nomenclature Stainless Steel Insert Orifice Trade Name Fan angle and flow rate- orifice size Extended Range VisiFlo Color Coding

Turbo Flat-fan Tapered edge, wide angle flat pattern Designed to work in flat-fan nozzle holder Uniform spray distribution Wide pressure range Large, drift resistant droplets 50% overlap Plastic with superior wear characteristics

Combo-Jet Nozzles/Add-a-Body: Nozzles designed for convenience and safety ER Series – Extended Range DR Series – Insert for Drift Reduction Tip insert a part of the cap w/screen Add-a-body allows applicators to use a combination of orifice sizes

Air-Assist Nozzles Where air is injected or drawn into the nozzle cavity and exits with the fluid.

Air/Induction – Venturi Nozzle Greenleaf – TurboDrop Air intake venturi section Mixing chamber - air and spray solution blended Pattern tip forms large air- bubble drops Exit tip flow 2X venturi orifice Better penetration? Reduced run-off? Improved coverage? Adequate efficacy? Reduced drift?

Air-Assist Sprayers: Where a curtain of high speed air is used to assist with particle movement after leaving the nozzle.

Air Assist Spraying: Process using pneumatic energy to aid in the atomization, transportation, penetration, and deposition of spray products. Air stream becomes the carrier. Potential for reduced rates of carrier and active ingredients.

Additional Strategies to Reduce Drift Increase flow rates - higher application volumes Lower spray (boom) height Lower pressure Clean nozzles Buffer zones

Buffer Zone An area where pesticide is not directly applied thereby providing protection to a defined area. Buffer zones are usually adjacent to sensitive or protected (as established by local, state, or federal regulation) areas. Buffer zone designation may be contingent upon: –state regulations –pesticide product labels –prevailing weather conditions –sensitive/protected area(s) National Coalition for Drift Minimization

Drift Management Plan If you think off-target drift may occur you must have a Drift Management Plan ahead of time. Reg 637 (Michigan’s Pesticide Control Act) Part 10

Drift Management Plan “P esticide application shall be made in a manner that minimizes off-target drift, unless prior authorization and consent as specified in subrule (3) of this rule is obtained from the owner or resident of land onto which drift may occur.” Reg 637 Part 10

Drift Management Plan “ When pesticide off-target drift is anticipated due to the nature of the application a drift management plan shall be utilized by the applicator to minimize the occurrence and adverse effects of off-target drift.” Reg 637 Part 10 (3)

Drift Management Plan The plan shall include provisions to secure the informed consent of residents in the affected area before making the application. Reg 637 Part 10

Drift Management Plan If drift occur when you did not anticipate it…... “…the applicator shall notify the resident in the affected area either verbally or with appropriate signs before leaving the area.” Reg 637 Part 10 Communication

Exchange of information To communicate you must also listen Positive attitude Open to change or new ideas Patience

Drift Management Plan Must be in writing Reviewed annually When implemented keep records of plan for: - One year for general use pesticide - Three years for RUP Applicator must comply with all federal and state regulations.

Michigan Department of Agriculture For more information: MSU Pesticide Education Program Michigan Farm Bureau