Optimizing

Herbicides

through

Adjuvants

Rich Zollinger

ND State University

Adjuvants are like a lot of things

some work and some don‟t

Minot, ND – January, 2011 Jan 28, 2014 = -49 F (wind chill)

Minot, ND – January, 2011

Dr. John Nalewaja

Dr. Frank Manthey

Dr. Alan Dexter

Dr. Cal Messersmith

Dr. Bill Ahrens

Dr. Brad Ramsdale

Dr. Kirk Howatt

>20 Visiting scientists from Europe and S. Africa

2011 2012 2013 FCS Nat Champions

Contributions to adjuvant/formulation development: Methylated Seed Oil (MSO)

Basic pH Blend

Hard water herbicide antagonism

Function of ammonium sulfate

Dr. Albert Einstein Kurt Gödel

Princeton University

1933-1955

Adjuvants are non-regulated

High cost of petroleum =

Change adjuvant formulations

Adjuvants are unregulated!

“Snake oil” “Mouse milk”

“High octane perfume”

slough water artesian water

alcohol antifreeze

H2O2 sugar

Blue windshield wiper fluid

Clorox Humic acid

Cell voltage regulators

RU WeatherMax = No surfactant use information

RU PowerMax =

Full surfactant load glyphosate label - 3 lb ae/gal =

Hard-to-wet Easy-to-wet

Which weed retains spray droplets the LEAST…

the most water repellant

Surface tension – droplets on leaf surface

Velvetleaf

Lambsquarters

Redroot pigeed

NIS

NIS

Droplet retention - So what!

Enlist and RU Xtend = New Technology

Cant use sloppy application

Particle drift (including inversions)

Volatilization

Sprayer cleanout - contamination

Misapplication

www.state.me.us

Emerging Weed Mngt Traits Dicamba resistant soybean (Monsanto/BASF)

• Follow Best Management Practices (BMPs)

- Nozzles = extreme-ultra coarse droplets - >450 µm

- <15 mph travel speed

- 3-10 wind speed

- <24 inch boom height

- Observe buffer zones

- Add drift reducing agent

- Sprayer clean out using triple rinse +

alkaline agent + detergent

- Do not add AMS

Open comment period ends Spring 2012.

Drift Reduction Technology (DRT)

Sprayer / Spray Solution

Modifications

Star rating determines buffer

distance around field perimeter!

Some DRT conclusions

Something has been forgotten in all this DRT

discombobulation – What is it?

Very coarse vs. Fine

Droplet size

28 days after application of phenoxy

type herbicide

Insight #3 - Water conditioner adjuvants?

Do they really condition water?

# 3

ND Weed Control Guide

= 600 to 1,200 ppm

= 120 to 600 ppm

= 50 to 150 ppm

= 20 to 150 ppm

=1,200 to 2,500 ppm

1,200 to 2,500 ppm

Lambsquarters

Glyphosate at 1 lb ae/A

Ca + Mg @ 1,000 ppm

Control with glyphosate as influenced by adjuvant 4 WAT,

Manhattan, KS 2005 – D. Peterson

Treatment

Rate

Velvet-

Leaf

Sorghum

Corn

Sun-

flower

---------------(% control)--------------

Roundup WMax +: 8 oz 40 60 52 73

AMS 5 % v/v 72 90 82 90

AMS + NIS 2.5% v/v 77 95 86 95

WCA #1 1.25% v/v 65 83 77 90

WCA #2 0.5% v/v 30 47 42 60

WCA #3 0.5% v/v 37 58 50 75

WCA #4 0.5% v/v 42 50 50 85

WCA #5 1% v/v 43 57 53 80

WCA #6 0.25% v/v 33 50 47 70

WCA #7 2.2 lb/100G 37 40 40 78

WCA #7 0.5% v/v 62 68 67 90

LSD (5%) 7 9 7 7

Water Conditioning Adjuvants –

standardized test method

Rich Zollinger – North Dakota State Univ.

Mark Bernards – U of Nebraska

Dallas Peterson – Kansas State University

Bryan Young – Southern Illinois University

Greg Dahl and Joe Gednalski – Winfield Solutions, MN

Water Conditioner adjuvants

• Request = Water conditioner (WC)

• Helfire = Acidic WC

• N-Tense = WC + NIS

• Array = AMS + Deposition + Defoamer

• Bronc Max = AMS + WC

• Choice Weather Master = AMS + WC

• Cayuse Plus = AMS + NIS

• Class Act NG = AMS + NIS

• Bronc Plus Dry EDT = AMS + NIS

• Flame = AMS + NIS

Glyphosate with water conditioners (1,000 ppm water hardness)

0 10 20 30 40 50 60 70 80 90 100

WC 10

WC 9

WC 8

WC 7

WC 6

WC 5

WC 4

WC 3

WC 2

WC 1

% control

Ve

lve

tle

af

Ave of 4 locations, 2010

+ NIS + AMS

+ NIS

Glyphosate with water conditioners (1,000 ppm water hardness)

0 10 20 30 40 50 60 70 80 90 100

WC 10

WC 9

WC 8

WC 7

WC 6

WC 5

WC 4

WC 3

WC 2

WC 1

% control

Ave

of

bro

ad

lea

f sp

ecie

s

Ave of 5 locations, 2010

+ NIS + AMS

+ NIS

Glyphosate with water conditioners (1,000 ppm water hardness)

0 10 20 30 40 50 60 70 80 90 100

WC 10

WC 9

WC 8

WC 7

WC 6

WC 5

WC 4

WC 3

WC 2

WC 1

% control

Ave

of

gra

ss s

pe

cie

s

Ave of 3 locations, 2010

Glyphosate with water conditioners (1,000 ppm water hardness)

0 10 20 30 40 50 60 70 80 90 100

WC 10

WC 9

WC 8

WC 7

WC 6

WC 5

WC 4

WC 3

WC 2

WC 1

% control

Ave

of

bro

ad

lea

f sp

ecie

s

Ave of 4 locations, 2010

WC 1 = 0.5% v/v

WC 2 = 0.5% v/v

WC 3 = 0.5% v/v

WC 4 = 0.5% v/v

WC 5 = 0.5% v/v

WC 6 = 9 lb/100 gal

WC 7 = 0.5% v/v

WC 8 = 0.5% v/v

WC 9 = 10 lb/100 gal

WC10 = 2.5% v/v

Emerging Weed Mngt Traits Dicamba resistant soybean (Monsanto/BASF)

• Follow Best Management Practices (BMPs)

- Nozzles = extreme-ultra coarse droplets - >450 µm

- <15 mph travel speed

- 3-10 wind speed

- <24 inch boom height

- Observe buffer zones

- Add drift reducing agent

- Sprayer clean out using triple rinse +

alkaline agent + detergent

- Do not add AMS

AMS

Volatility of dicamba Volatility

Banvel = dicamba-dma salt 3% (dimethyl amine)

Clarity = dicamba-dga salt 0.3% (diglycol amine)

Engenia = dicamba- BAPMA salt 0.03% (Bis(3-aminopropyl)methyl amine))

Banvel + AMS >3% (?)

Clarity + AMS >3%

Engenia + AMS ~0.3%

How much dicamba can induce soybean injury?

Insight #4 - Adjuvant use in glyphosate

tank-mixtures?

Conundrum!

Hydrophilic glyphosate +

Lipophilic tank-mix herbicide

# 4

#1 Soybean Weed in NC Region

?

#1 Soybean Weed in NC Region

The “Fantastic Five” tankmix pardners

Glyphosate +

1. Clethodim (Select)

2. Dicamba (Status)

3. Laudis/Impact/Callisto (HPPD)

4. Sharpen

5. Flexstar

Conundrum with adjuvant selection!

ND Weed Control Guide

ASTM Adjuvant Defintions

HSOC = enhance lipophilic herbicide without antagonizing glyphosate (hydrophilic herbicide).

ASTM Adjuvant Defintions

Crop oil concentrate (PO) = emulsifiable petroleum oil-based products containing 15-20% surfactant and remainder phytobland oil.

High surfactant oil conc. (HSOC) = emulsifiable oil (PO or MSO) based products containing 20-50% surfactant and a minimum of 50% oil.

HSOC definition = enhance lipophilic herbicide without

antagonizing glyphosate.

Oil adjuvants with Glyt + Laudis (Flax and 4 broadleaf species (ave)

0 10 20 30 40 50 60 70 80 90 100

-4

-3

-2

MSO-HSOC-1

-2

PO-HSOC-1

-2

MSO-1

MSO + OS

-2

PO-1

Glyt + Laud +

% control

Oil

ad

juvan

ts

= Flax

= Ave 4 species:

(amar, colq, tabw,

conv. soy)

Zollinger, 2010

0.28 lb ae + 1 fl oz

1 qt/A

1 qt/A

0.75% v/v

1.25 pt/A

1.25 pt/A

1 pt/A

1 pt/A

1 pt/A

1 pt/A

1 pt/A

0.5 pt/A

COC / PO

MSO

MSO+OS

PO-HSOC

MSO-HSOC

LSD (0.05) = 5

MSO+NIS

Insight #7 - Oil Adjuvant Rate

Volume versus Area?

Which concept is best?

# 7

Oil Adjuvant Rates - Historical

Movement from area (pt/A) to volume (% v/v)

Label rates Grower rates

PO/COC

MSO

HSOC

Oil Adjuvant Rates - Historical

Movement from area (pt/A) to volume (% v/v)

Label rates Grower rates

PO/COC 2 pt/A 1%

MSO 1.5 pt/A 1%

HSOC 0.75-1 pt/A 0.5%

Oil adjuvant recommendations

Herbicide Oil 28% AMS -v/v- - v/v - /100 gal

Raptor (BASF) 1-2% 2.5% 12-15 lb

Assure II (Dupont) 1% 2 qt/A 2 lb/A

FirstRate (Dow) 1.2% 2.5% 8.5-17 lb

Valor (Valent) -- 1-2 qt/A 2-2.5 lb/A

Impact (Amvac) 1-1.5% 1.25-2.5% 8.5-17 lb

Callisto (Syngenta) 1% 2.5% 8.5 lb

Oil adjuvant recommendations

Herbicide Oil 28% AMS -v/v- - v/v - /100 gal

Select (Arysta/Valent) 1% or 1qt 1-2 qt /A 2.5-4 lb/A

>1 pt/A

Laudis (Bayer) 1% but

>1.25 pt/A 1.5 qt/A 1.5 lb/A

Status (BASF) 1-2 pt/A 1.25% 5-17 lb

Sharpen (BASF) 1%....>1 pt/A 1.25-2.5% 8.5-17 lb

2010 Extension Specialist Survey Spray volume used (gpa):

State University Grower

ND 8.5 10

SD 20 10

NE 15 10

KS 15 5 to 10

MN 20 10 to15

WI 15 to 20 10

MI 19 10 to 15

Ontario 20 10 to 15

IA 20 8 to 15

IL 20 12 to 15

IN 15 12 to 15

TX 20 8 to 10

Low gpa =

glyphosate

Should adjuvants be applied at % v/v or by area?

Atrazine = 1 qt/A of oil adjuvant

Assure II, Fusidale DX, and Fusion = 1% v/v oil

At 18 gpa - 1% v/v PO = 0.18 gal = 1.5 pt/A

At 9 gpa - 1% v/v PO = 0.085 gal = 0.68 pt/A

At 4.5 gpa – 1% v/v PO = 0.043 gal = 0.34 pt/A

Question:

Oil volume with Laudis (Zollinger, 2008)

MSO

Spray vol. 1% v/v 1.5 pt/A (gpa) -------- % control -------

(Ave of 4 species)

8.5 (0.7 pt/A) 46 69

17 (1.4 pt/A) 55 54

LSD (0.05) ------ 7 ------

Sharpen with oil volume, Zollinger, 2010

Ave of 4 broadleaf species

0 10 20 30 40 50 60 70 80 90 100

2 pt/A

1.4 pt/A

0.7 pt/A

0.34 pt/A

2 pt/A

1.4 pt/A

0.7 pt/A

0.34 pt/A

% control

Pe

tro

l. O

il P

O -

HS

OC

0.5% 0.25%

1% 0.5%

2% 1%

3% 1.5%

= 8.5 gpa = 17 gpa

0.5% 0.25%

1% 0.5%

2% 1%

3% 1.5%

Compare 1% v/v to 2 pt/A

Compare 0.5% to 1 pt/A

Sharpen with oil volume, Zollinger, 2010 Ave of 4 broadleaf species

0 10 20 30 40 50 60 70 80 90 100

2 pt/A

1.4 pt/A

0.7 pt/A

0.34 pt/A

2 pt/A

1.4 pt/A

0.7 pt/A

0.34 pt/A

% control

MS

O

MS

O -

HS

OC

0.5% 0.25%

1% 0.5%

2% 1%

3% 1.5%

= 8.5 gpa = 17 gpa

0.5% 0.25%

1% 0.5%

2% 1%

3% 1.5%

Compare 1% v/v to 1.4 pt/A

Compare 0.5% v/v to 1 pt/A

Compare 1% v/v to 1.4 pt/A

General rule:

Apply oil adjuvants at 1% v/v but not

less than 1.25 pt/A.

Herbicide optimization:

1. Better adjuvant use information on labels.

2. Add NIS especially for „hard to wet‟ species.

3. Use “water conditioners” that contain at least AMS at

8.5 lb/100 at use rates.

4. MSO-HSOCs adjuvants enhance glyt+oil herbicides.

5. Alkaline pH water enhance herbicide solubility and

may enhance some herbicides.

6. Acidic AMS Replacement (AAR) adjuvants are

variable but can some can equal AMS + NIS.

7. Apply oil adjuvants on an area basis (pt/A).