1. Pesticide Formulations and Adjuvants
Montana State University
Pesticide Safety Education Program

2. What is a formulation? How a pesticide is packaged. Contains:
Active Ingredient
Inert Ingredient

3. Active Ingredients Has the pesticidal effect Its on the label
Properties of the a.i. influences the type of
formulation

4. Inert Ingredients “Inactive” ingredients mixed with a.i. To make
formulation easier to handle or store.
Toxic or non-toxic

5. Can you get the same reaction from the same active ingredients regardless of inert ingredients?
NO, Inert Ingredients are often patented and are only known to the company.
Many times this is the difference between a product working effectively and not at all.
BANDED, SEED, FOLIAR applications all different yet the same!

6. Types of Formulations
Wet
More easily absorbed
Dry
More easily inhaled

7. Liquid Formulations (Wet)
EC –emulsifiable concentrate
S – soluble
M or ME – Micro-Encapsulated
ULV – ultra low volume

8. Soluble Advantage: Disadvantage:
☺ Will not separate or settle out when mixed with water.
☺ Not as harmful to non-target plants
and animals
Disadvantage:
Not many disadvantages.
Readily absorbs into skin

9. Emulsified Concentrates
ADVANTAGES
☺ Little agitation required. Won’t settle out when equipment is turned off.
☺ Relatively non-abrasive.
☺ Easy to handle, store and transport
DISADVANTAGES
Because of the solvents and emulsifiers, EC’s are a hazard
to non-target plants and animals.
Easily absorbed through skin of plants and humans.
Solvents may cause rubber or plastic hoses & gaskets to
deteriorate.

10. Dry Formulations WP – Wettable powder F or DF – Dry Flowable
WDG – Water Dispersible Granule
D -Dust
P or G – Pellets or Granules

11. Wettable Powders ADVANTAGES plants DISADVANTAGES
☺ Easy to store & transport. Smaller packaging. Won’t
freeze.
☺ Less inert ingredients in formulation.
☺ Lower toxicity to plants than liquid formulations.
The inert ingredients, clay or talc, are generally harmless to
plants
DISADVANTAGES
Inhalation hazard when pouring and mixing. It’s dry!
Needs vigorous & constant agitation in the spray tank.
Abrasive to many pumps and nozzles.

12. Flowable ADVANTAGES ☺ Easy to handle and apply
☺ Seldom clogs nozzles. Finer ground carrier.
DISADVANTAGES
May leave visible residue.
Requires agitation

13. Granules or Pellets ADVANTAGES DISADVANTAGES
☺ Ready to Use (RTU); no mixing
☺ Low drift hazard as particles settle quickly.
☺ In most cases, don’t need to mix with water first.
DISADVANTAGES
May need to be incorporated into the soil.
Dust from application equipment might present hazard to applicator.
Easy to over apply

14. Effects of Different Formulations
Formulations Hazards Phytox Equipment Agitate Compactable
M or ME Dermal Safe ok Yes Fair
G or P Inhale Safe NA NA NA
D Inhale Safe NA NA NA
S Dermal Safe Non-abrasive No Fair
F or FL Dermal Maybe abrasive Yes Fair
EC Dermal Maybe Seals, gaskets No Fair
WP Inhale Safe abrasive Yes High

15. Testing Compatibility Using 1 qt jar
Wear your PPE!
Add to jar in same proportions as you use in the field ( 1
teaspoon = 1 quart of pesticide added to 50 gallons of water).
Add half of diluent to jar then add pesticide according to
plan.
Add Wettable & other powders & Water-dispersible granules
Agitate and add remaining diluent
Add the Liquid products, such as solutions, surfactants and
flowables.
Add Emulsifiable concentrates last.
Shake jar vigorously and feel sides of jar for heat. Check for
lumps, scum and clumps

16. continued Let the jar sit for 5 minutes.
Check for any flakes, sludge, gels or other
precipitants.
Also see if there is any separation or layering, or
small oil particles in solution.
If separate layers are formed after sitting up to 30
minutes but can be resuspended by shaking,
application may be possible but make sure you
have agitation in the sprayer.
If there is layering, an emulsifiable concentrate
will normally go to the top. Wettable powders will
either settle to the bottom or float on top.

17. Interaction problems with combining Formulations
Additive effects
Synergistic responses
Antagonism
Enhancement

18. Additive Effect SAVES TIME WITH NO CHANGE IN EFFECT! Ease of mixing
Reduces # of field passes
Example: root absorbed herbicide with a
foliar absorbed or Tordon with Escort

19. Synergistic Response Confused with Additive effects
Greater response when mixed.
True interaction between chemicals
Reduced rates often the result

20. Antagonism Less control when 2 or more chemicals are mixed
May also increase phytotoxicity
Example: mixing of some grass and
broadleaf herbicides (Diclofop and 2,4-D)

21. Enhancement When a pesticide is mixed with an additive
to provide greater response.
Example: adjuvants

22. Adjuvants
Additives that are added to a spray solution in order to enhance or modify the performance of the spray mixture.
#1 - Surfactants/wetting agents
#2 - Oils
#3 - Fertilizers
#4 - Utility

23. #1 - Surfactants
A broad category of adjuvants that facilitate and enhance the absorbing, emulsifying, dispersing, spreading, sticking, wetting and penetrating properties of pesticides.
Some pesticides like Roundup Pro already have surfactants added. (14.5 %)

24. Why Surfactants
Because of the high surface tension of water, spray mixture droplets maintain their roundness and can sit on the leaf hairs or leaf surface without much of the mixture actually contacting the leaf.
Surfactants reduce angle and promote more absorption

25. Classes of Surfactants/Wetting Agents
#1a - Nonionic Surfactants (no charge)
Reduces surface tension
Improves spreading, sticking and herbicide uptake
All purpose
#1b - Silicone compounds (Silicone based)
More reduction in surface tension.
Spread more than conventional surfactants
Maximum rainfastness due to increased absorption.
Can usually use at lower rates

26. #2 - Oils Crop Oil Concentrates (COC)
Blend of paraffin based petroleum oil and surfactants
Used primarily with grass herbicides
Esterified Seed Oils (ESO) often referred as MSO
Produced by reacting fatty acids from seed oils(corn, soybean, canola) with an alcohol to form an ester
All purpose type of surfactant

27. #3 - Fertilizers -(Nitrogen-surfactant Blends)
Improves herbicide uptake with hard to-kill weeds
Neutralizes or gives hard water mineral ions something to bind to instead of the herbicide.
Used primarily with broadleaf herbicides.

28. #4 - Utility Acidifiers -neutralize alkaline solutions & lower pH.
Buffering agents -stabilize the pH of spray solutions.
Anti-foaming agents
Compatibility agents
Drift control agents
Emulsification aids
Suspension aids -added to a suspension in order to keep pesticide particles dispersed or to resuspend particles.

29. Tips continued Costs What conditions follow an application?
Generally, non-ionic surfactants and crop oil concentrates are the least expensive
Nitrogen surfactants, esterified crop oils, organosilicones (most expensive)
What conditions follow an application?
Max rainfastness: esterified seed oils, organo-silicones, nitrogen surfactants
Not all surfactants have the same amount of rainfastness

30. What formulation is this?
FLOWABLE
DERMAL ABSORPTION
Examples:
Bravo 720 F fungicide
Furadan 4 F insecticide

31. Question #2 What formulation is this?
Powdered Hand Soap
Wettable Powder
Easily Inhaled
Examples:
Sevin 50 W insecticide
Kerb 50 W herbicide
Sniper 50 W insecticide

32. READ THE LABEL
This will give you an idea of what type of adjuvant if any should be used.

33. Questions