2002 Cotton Production Workshop

Tifton, GA

Culpepper and York

Topics for Discussion

1. Burndown for conservation tillage

2. Liberty Link Technology

3. Roundup Ready Flex

4. Early-season weed competition

5. Touchdown + Dual Magnum

6. CGA 362622 = Envoke; Suprend

7. Aim (directed treatments

8. Valor (directed treatments)

9. Roundup resistance concerns

10. Tropical spiderwort

11. Morningglory

12. Palmer amaranth

13. Glyphosate formulations

Cotton Burndown

Cotton BurndownFocus: cutleaf eveningprimrose

1. Put 2,4-D out in Feb/March followed by glyphosate or paraquat near planting

2. Apply glyphosate or paraquat + 2,4-D near planting (be aware of plant back interval)

Cotton Burndown

1. Put 2,4-D out in Feb/March followed by glyphosate or paraquat near planting

a) better weed coverage, smaller weeds

b) very flexible at planting

c) no plant back issues

d) tank hopefully cleaned out by now

e) two trips are necessary

Cotton Burndown

2. Apply glyphosate or paraquat + 2,4-D near planting (be aware of plant back interval)

a) plant back restrictions

b) weed coverage questionable

c) tank cleanout more of an issue

d) single application

If you want use 2,4-D then

Glyphosate plus Clarity*

Or

Glyphosate plus Valor*

*Beware of plant back restrictions

Relative Response of Cutleaf Eveningprimrose to Glyphosate Tank Mixes.*

*Estimates based on GA and NC data 30 DAT from 1999 to 2002.

0

0.5

1A

lone

Aim

Har

mon

yE

xtra

Goa

l

Res

ourc

e

Val

or

Cla

rity

2,4-

D

16 6 13 6 6 12 7 16 # of trials

Roundup UltraMax (1.6 pt) + 1.5 pt Caparol

Wheat Response to Glyphosate Applied Alone and in Mixture with Caparol. Ponder Farm, 2001; 16 DAT.

Summary - cutleaf eveningprimrose

1. 2,4-D, glyphosate + 2,4-D, paraquat + 2,4-D

2. glyphosate + Valor or Clarity

Percent primrose control by Liberty. Tifton, 2002. 33 day after treatment.*

0

20

40

60

80

100

20 oz 27 oz 32 oz

Liberty

56

8593

*Not an economical option at this time.

Wild Radish

Wild Radish Impact on Cotton Emergence

Wild radish Cotton stand

residue* reduction

0.5 29

1.0 78

1.5 100

2.0 100

*percent of soil by weight. Jason Norsworthy, Clemson University.

Summary - Wild radish

1. glyphosate + 2,4-D, Harmony Extra

paraquat + 2,4-D, Direx, Harmony Extra

2. glyphosate + Valor, Direx

3. glyphosate

Liberty Link Cotton

Liberty Link (2003)

1. Approximately 15 bags per sales rep

2. 2 cultivars: 989 and 966 series, no Bt

Liberty Link (2004)

Liberty is expensive…..how will it compete

Liberty Link (2004) – One Possibility

Roundup Ready Seed + 2 application of glyphosate

equals (approximately)

Liberty Link Seed + 2 applications of Liberty (32 oz)

Liberty vs. Roundup* Weed Liberty Roundup

Application window + -

Eveningprimrose + -

Goosegrass - +

Large grasses - +

Morningglory + -

Nutsedge - +

Palmer amaranth - +

Perennial grasses - +

Volunteer peanut + -*Control of many weeds is similar. Assuming proper rates and application.

Pitted Morningglory Response to Liberty and Glyphosate. Moultrie, GA, 2001.

non-treated Liberty glyphosate

(27 oz/A) (0.75 lb ae/A)

non-treated Liberty (27.4 oz/A)LL cotton trial, TyTy, 2001.

Palmer must be small for Liberty

Possible Liberty Link Systems1. Yellow herbicide at plant,

Liberty 1-2 leaf topical,

Liberty 6-8 leaf topical,

timely directed

2. Yellow plus Cotoran or Staple,

Liberty timely 3- 6 leaf,

timely directed

Roundup Ready Flex

1. Will contain new transformation event

2. Greater gene expression in floral parts

3. Greater tolerance to later overtop applications

4. 2006???

Roundup Ready Flex tolerance study. 2002.Mechanically harvested seed cotton yield.

0

500

1000

1500

2000

2500

lb/A

Old event** New event**

0

1.5

2.25

lb ae/A*

*Applied overtop 3-, 6-, 10-, and 14-leaf.

**Not in commercial variety.

Early Season Weed Competition

2 inch weeds 5 inch weeds 8 inch weeds

Application Timing

Early Season Competition

1. First 4 to 6 weeks still most important for weeds

2. Approximately 40% of time use PRE or be willing to make 2 topical applications

following label recommendations.

Effect of PRE Herbicides on RR Seedcotton Yield.1

0

300

600

900

1200

1500

lb/A

1 OT

1070 b

1460 a

No PRE Avg. 10 PRE’s

1Study in 1998 conducted at Goldsboro, NC.

Trifloxysulfuron-sodium

•Trifloxysulfuron-sodium is a post-emergence, broad-spectrum, ALS inhibitor herbicide

•Trifloxysulfuron will be marketed in two brands:

• Envoke – 75WG trifloxysulfuron

• Suprend – trifloxysulfuron + prometryn

Envoke

1. New product from Syngenta

2. Fourth quarter EPA work plan

3. Broadleaf and sedge herbicide, do NOT mix with graminicides

4. Short soil residual; limited PRE activity

Envoke vs. Staple* Weed Envoke Staple

Application window +

Dayflower species ++

Morningglory +

Nutsedge ++

Palmer amaranth +

Prickly sida ++

Sicklepod ++

Smallflower mg** ++

Tall morningglory ++*Assuming proper postemergence rates and application.

**Absolutely no control by Envoke

Zorial PRE + Envoke 0.0047 LB A/A14 DAT

Envoke applied under Envoke applied under

favorable conditions dry conditions14 DAT

glyphosate Envoke

Smallflower Morningglory Control. 14 DAT.

Envoke

Mix with Staple or glyphosate:

Apparently NO

Envoke

Where might Syngenta promote the herbicide?

Syngenta RR Cotton Herbicide ProgramSyngenta RR Cotton Herbicide Program

plus

Untreated check Glyphosate + Dual 1- to 2-leaf

Envoke 5- to 8-leaf

Nutsedge Control with Envoke

Injury Issues with Envoke

Expect some injury. Usually moderate but occasionally severe. Recovers quickly with no yield loss in most studies across Southeast.

Envoke 0.0047 lb/A OT 4-lf Non-treated Control

Suprend• New cotton herbicide from Syngenta

• Contains trifloxysulfuron-sodium + prometryn

at 1:133 ratio

• Formulated as 80% WDG

• Applied postemergence-directed

• Use rate of 1 to 1.5 lb/acre

1.0 lb Suprend 1.6 pt Caparol

1.5 lb Suprend 2.4 pt Caparol

• Broadleaf weeds and nutsedge; weak on grasses

~

~

Syngenta Cotton Herbicide Program

+ Dual MAGNUM

Touchdown plus Dual Magnum

1. Apply to cotton > 3” but before 5 leaf stage

2. Do not use ANY additive, avoid dew

Injury Range

From glyphosate plus Dual

Cotton Response to Glyphosate + Dual*

heavy dew no dew

*Application with dew applied 7 am. Application without dew applied 11 am.

Touchdown plus Dual Magnum

1. Apply to cotton > 3” but before 5 leaf stage

2. Do not use ANY additives, avoid dew

3. Do not mix with staple

Do not apply Dual and Staple within a couple of days of each other

glyphosate + Dual glyphosate + Dual + Staple

Touchdown plus Dual Magnum

1. Apply to cotton > 3” but before 5 leaf stage

2. Do not use ANY additives, avoid dew

3. Do not mix with staple

4. Residual weed control of pigweeds, grasses, pusley, and spiderwort

glyphosate @ 4 leaf cotton + Dual Magnum 1 pt/A

1) Dayflower emerged 3 to 7 day after 4 leaf application. Rain 3 d after application.

2) Prowl applied PRE. No layby.

glyphosate @ 4 lf + 1 pt Dual MagnumAttapulgus, 2001

*Irrigated within 48 hrs.

Dual vs. Staple in Glyphosate Topical Mixture*

Weed Dual Staple

Annual grasses ++

Dayflower species ++ +

Florida pusley +

Morningglory ++

Nutsedge +

Palmer amaranth ++ ++

Sicklepod

Cost of treatment ++*Assuming proper postemergence rates and application.

Dual Magnum PRE

Do Not Use Dual PRE on Georgia Soils

• label claims control of:

pigweed species lambsquarters

cocklebur morningglory

velvetleaf spurred anoda

smartweed hemp sesbania

common ragweed

Aim Postemergence-directed

Most Likely Fit for Aim in Cotton

Tank mix with glyphosate to improve

morningglory control

Roundup UltraMax 1.6 pt

Large Morningglory Response to Layby Herbicides. 5 DAT. Irwin Co., GA, 2001.

*Trial conducted on farm in Irwin County with Gibbs Wilson.

+ Aim 0.6 oz/A

Most Likely Fit for Aim in Cotton

What about tank mixing with other products for morningglory control?

Glyphosate + Aim Glyphosate alonedirected applications

Plant terminal response to Aim “running” the stem

Aim Application Timing

Treat Aim as a true layby directed herbicide applying when cotton is at least 16 inches tall and the stem is completely woody.

• 4th quarter 2003 EPA workplan

• 18 inch cotton or larger, completely “woody”

• glyphosate plus 1-2 oz per acre

• MSMA plus 2 oz per acre

• postemergence control of most weeds

• residual control of many weeds

Valor for Layby (2004)

Large Morningglory Response to Layby Herbicides. 5 DAT. Irwin Co., GA, 2001.

*Trial conducted on farm in Irwin County with Gibbs Wilson.

UltraMax 1.6 pt + Valor 1 ozRoundup UltraMax 1.6 pt

• Off-labeled use of this product in 2003 could jeopardize the potential for a 2004 label

Valor for Layby (2004)

Weed Resistance

to Glyphosate

Weed Resistance to Glyphosate:

Should We Be Concerned?

Weed Resistance to Glyphosate:

Should We Be Concerned?

ABSOLUTELY!

Known Cases of Resistance to Glyphosate

Species Location

Goosegrass Malaysia

Rigid ryegrass California, Australia,

South Africa

Italian ryegrass Chile

Horseweed Tennessee, Delaware

HORSEWEED

How Can We Deal With Resistance?

1. Take your chances, deal with it

if and when it happens

2. Manage to avoid it, or at least delay

its development

Practical Things to Help Avoid Resistance

1. Avoid over-reliance on same mode of action

a. Rotate modes of action

b. Use more than one MOA

Tank mixes, sequential applications

Practical Things to Help Avoid Resistance

1. Avoid over-reliance on same mode of action

a. Rotate modes of action

MOA tables in Extension pubs or online

b. Use more than one MOA

Tank mixes, sequential applications

2. Integrate non-chemical control, such as

cultivation and primary tillage, where practical

Detecting Herbicide Resistance

• Most control failures NOT due to resistance

• Eliminate other possible causes first

– Inadequate herbicide rate – Poor/improper application– Poor timing of application– Unfavorable weather– Later weed flushes– Antagonism by other pesticides

Indicators of Resistance

• Performance poor on one species, other species controlled well

• Product normally controls weed in question

• Poor control confined to spots in field

• Some plants of species in question controlled well, others controlled poorly

Progression of

Herbicide Resistance

Year 1

Year 2

Year 5

Year 3

Year 4

Weed Shifts are a greater issue at this

time in Georgia cotton

Asiatic dayflower Spreading dayflower

Tropical

spiderwort

above ground below ground

seed seed

below ground fruiting structures

Spiderworts rank as Georgia’s Most troublesome weeds in cotton

1999: not ranked

2001: ninth

2003: number 1

Spiderwort response to Roundup UltraMax*

20 oz 0 oz 30 oz 0 oz

40 oz 0 oz 50 oz 0 oz*Pictures 15 d after treatment. No plants died from any treatment.

37 “systems” evaluated at 2 locations to control tropical

spiderwort in 2002.Control at harvest:

< 50% control: 49

50 to 80% control: 19

80-90% control: 5

>90% control: 1

Grady Co. 2002

What do we know from 2002?

Greater than 85% residual control at 30 days: Command Dual (can not use at plant)

Greater than 70% residual control at 30 days: Cotoran

Direx* Zorial

*Caparol or Cotton-Pro not included in trial.

What do we know from 2002?

Postemergence control (<3 inch):

1. Paraquat (Gramoxone, Boa) (>90%)

2. MSMA (2 lb/A) tank mixes (80-90%)

3. Glyphosate + Aim, Direx, Staple (70-85%)

What do we know from 2001-2002?

Best system so far:

Prowl/Treflan at plant (no effect on spiderwort)Glyphosate + Dual early POSTDirex (1 qt) + MSMA (2 lb/A) directed

All applications were EXTREMELY timely.

Percent tropical spiderwort control at cotton harvest. Grady County, 2001-2002.

0

20

40

60

80

100

2001

2001

2002

2002

Yellow herbicide at plant; glyphosate + Dual early Post; Direx + MSMA directed

57

95

7887

What do we know from 2002?

1) We must get more residual in the program

2) Where do we put the residual

3) We must learn spiderwort emergence pattern

4) If you don’t have the weed; make sure you don’t get it.

Tropical Spiderwort Infestation

Red = severeOrange = moderateGreen = lightYellow = exist Gray = not found

Morningglory Continues to be Troublesome to Georgia Growers?

WHY??????

Morningglory Continues to be Troublesome to Georgia Growers?

At plant: Cotoran, Direx, Staple

Early Post: Glyphosate, Staple, Staple Plus

Directed: MSMA plus Caparol, Cobra, Cotoran, Direx, Staple, glyphosate plus Aim, Caparol, Direx, Harvade, Staple

Morningglory Continues to be Troublesome to Georgia Growers?

1) Timeliness of application(i.e. large at time of application)

2) No residual in the system

Residual Morningglory Control?

• Cotoran

• Direx

• Staple

• Caparol

Fairly common scene at harvest across the state

Two Possible Issues?

1. Pigweed is to large at time of layby

2. Pigweed comes up after layby

Two Possible Issues?

1. Pigweed is to large at time of layby

a) add a preemergence herbicide such a yellow herbicide, Cotoran,

Staple

b) Add Dual or Staple in at early POST

Two Possible Issues?

2. Pigweed comes up after layby

a) use layby option with residual activity such as Direx, Caparol, Prowl

Glyphosate

Formulations

Glyphosate Formulations

• Numerous brands available

• All registered for burndown,

selective applicators, and preharvest

• Most, but not all, registered

for use in RR crops

Registered Uses on Roundup Ready Crops

Brand Soybean Corn Cotton

Clearout 41 Plus Yes Yes Yes

Gly-4 Yes Yes Yes

Gly-4 Plus Yes Yes Yes

Gly-Flo No Yes No

Glyfos Yes Yes Yes

Glyfos X-TRA Yes Yes Yes

Glyphomax Yes Yes Yes

Glyphomax Plus Yes Yes Yes

Gly Star Original Yes Yes Yes

Gly Star Plus Yes Yes Yes

Roundup Original Yes Yes No

Roundup UltraMax Yes Yes Yes

Roundup WeatherMax Yes Yes Yes

Touchdown Yes Yes Yes

Glyphosate Formulations

• Numerous brands available

• Three basic formulations

O O

HO-C-CH2-N-CH2-P-OH

Glyphosate acid

= =

O O CH3

HO-C-CH2-N-CH2-P-OH2N-CH

CH3

Glyphosate isopropylamne salt

= =

O O

H3NO-C-CH2-N-CH2-P-ONH3

Glyphosate diammonium salt

= =

O O

HO-C-CH2-N-CH2-P-OK

Glyphosate potassium salt= =

Glyphosate Formulations• Some brands are “loaded”, some

require surfactant; AMS and drift control agent can be added to any

• Formulations and concentrations vary;

only way to compare use rates is on the basis of acid equivalence

Basic Glyphosate Formulations

Formulation Brand lb salt/gal lb ae/gal

diammonium Touchdown 3.57 3.0

salt

potassium Roundup 5.5 4.5

salt WeatherMax

isopropylamine All except 4.0 3.0

salt the above 5.0 3.7

5.4 4.0

Formulation lb salt/gal lb ae/gal Comparative rates

IPA salt 4.0 3.0 0.375 lb ae = 16 fl oz0.563 lb ae = 24 fl oz0.750 lb ae = 32 fl oz

IPA salt 5.0 3.7 0.375 lb ae = 13.0 fl oz0.563 lb ae = 19.5 fl oz0.750 lb ae = 26.0 fl oz

DA salt 3.57 3.0 0.375 lb ae = 16 fl oz0.563 lb ae = 24 fl oz0.750 lb ae = 32 fl oz

K salt 5.5 4.5 0.375 lb ae = 10.7 fl oz0.563 lb ae = 16.0 fl oz0.750 lb ae = 21.3 fl oz

So, which brand of glyphosate should you use?

So, which brand of glyphosate should you use?

1. Crop and weeds apparently don’t care

So, which brand of glyphosate should you use?

1. Crop and weeds apparently don’t care

2. Pricing is important

So, which brand of glyphosate should you use?

1. Crop and weeds apparently don’t care

2. Pricing is important

3. Also consider service and guarantees

So, which brand of glyphosate should you use?

1. Crop and weeds apparently don’t care

2. Pricing is important

3. Also consider service and guarantees

4. Should you consider future

developments in technology?

Roundup WeatherMax

1. Replacing UltraMax

2. Potassium salt

5.5 lb salt/gal; 4.5 lb ae/gal

3. 30-min rainfree warranty

4. Claim better activity under marginal

conditions

5. Better bulk handling characteristics

2002 Cotton Production Workshop

Tifton, GA

Culpepper and York