Pesticide Drift

1
Pesticide Drift
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,

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

2
Pesticide Drift

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

3
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
4
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
5
Pesticide drift does NOT include

• Erosion
• Volatilization
• Windblown soil particles

6
This is Pesticide Drift
7
Types of Drift

• Vapor Drift Volatilization or evaporation of
  pesticide from crop or soil that occurs after
  application.

8
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

9
Factors Affecting Drift

• Spray characteristics
• Chemical
• Formulation
• Additives
• Drop size
• Evaporation

10
More Factors Affecting Drift

• Equipment and Application
• Nozzle type
• Nozzle size
• Nozzle orientation
• Nozzle pressure
• Boom height

Turbo flat fan
Air-assist sprayers
11
Still More Factors

• Weather
• Air movement
• Temperature and humidity
• Inversions
• Topography

12
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.

13
Temperature and HumidityDroplet Evaporation

• Low relative humidity high temperature

High relative humidity low temperature
wind
14
Weather Wind Speed and Direction

• Sensitive areas buffer zones
• Dont 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.

15
Inversion Layer
16
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

Diagram of wind around a building. Adapted from
Farm Structures
Adapted from Survey of Climatologic Griffiths
and Driscoll, Texas AM University, 1982
H.J. Barre and L.L. Sammet, Farm Structures
(Wiley, 1959)
17
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

18
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.
19

• 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

20
Cutting Droplet Size in HalfResults in Eight
Times the Number of Droplets
250 Microns
250 Microns
500 Microns
250 Microns
250 Microns
250 Microns
250 Microns
250 Microns
250 Microns
21
Nozzle Selection

• Designed to reduce drift and improve droplet
  size control.

22
Selecting the Proper Nozzle

• Legal issues!!
• Following the label!

23
Nozzle Dropsize Classification
Selection based on droplet size

• Very Fine
• Fine
• Medium
• Coarse
• Very Coarse

• lt119 ?m
• 119-216 ?m
• 217-353 ?m
• 354-464 ?m
• gt464 ?m

Insecticides and Fungicides
Herbicides and Postemergence
Soil Applications of Herbicides
24
Nozzle Nomenclature
Extended Range
Trade Name
Stainless Steel Insert Orifice
VisiFlo Color Coding
Fan angle and flow rate-orifice size
25
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

26
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

27
Air-Assist Nozzles

• Where air is injected or drawn into the nozzle
  cavity and exits with the fluid.

28
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?

29
Air-Assist Sprayers

• Where a curtain of high speed air is used to
  assist with particle movement after leaving the
  nozzle.

30
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.

31
Additional Strategies to Reduce Drift

• Increase flow rates - higher application volumes
• Lower spray (boom) height
• Lower pressure
• Clean nozzles
• Buffer zones

32
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
33
Drift Management Plan

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

34
Drift Management Plan
Reg 637 Part 10

• Pesticide 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.

35
Drift Management Plan
Reg 637 Part 10 (3)

• 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.

36
Drift Management Plan
Reg 637 Part 10

• The plan shall include provisions to secure
  the informed consent of residents in the affected
  area before making the application.

Communication Communication
37
Drift Management Plan
Reg 637 Part 10

• 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.

Communication Communication
38
Communication

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

39
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.

40
For more information

• Michigan Department of Agriculture

http//www.michigan.gov/mda

• Michigan Farm Bureau
• http//www.michiganfarmbureau.com/

• MSU Pesticide Education Program
• http//www.pested.msu.edu