Cotton Production Workshop A. Stanley Culpepper

Breakout Session Objectives 1. New labels or uses 2. RR cotton tolerance to glyphosate 3. Managing weeds that are difficult to control in RR cotton 4. Glyphosate/tank mixes 5. Replacing Bladex 6. Cadre carryover 7. DNA application timing in strip-till 8. Layby applications in liquid N

New Labels or Uses 1. Paraquat formulations: Boa (2.5 lb ai) Gramoxone Extra (2.5 lb ai) Gramoxone Max (3.0 lb ai) 2. Glyphosate formulations:

Glyphosate Formulations* Acquire Credit DuPont Glyphosate Gly-Flo Glyfos Glyfos X-TRA Glyphomax Glyphomax Plus Glyphosate Original Rattler Roundup D-Pak Roundup Original Roundup Ultra Roundup UltraDry Roundup UltraMax Touchdown *Products in orange may be applied overtop of RR cotton according to label.

Roundup Ready Cotton Tolerance to Roundup, Touchdown, and Touchdown 5. Clayton, NC * Roundup Ultra 0 0 Touchdown 0 0 Touchdown % injury 1 application2 applications *Glyphosate applied at 1 lb ai/A. ACY

Roundup Ultra84 Roundup + Harvade92 Roundup + Harvade + COC99 Harvade + MSMA + COC99 Smallflower morningglory Morningglory Control in RR Cotton by Harvade Mixtures. Attapulgus, GA * *Roundup Ultra 2 pt/A; Harvade 6 oz/A when mixed with RU and 10 oz/A when mixed with MSMA; MSMA 2.67 pt/A

Breakout Session Objectives 1. New labels or uses 2. RR cotton tolerance to glyphosate

Transgenic Cotton Acreage in Georgia %

Lint Cotton Yields in RR Cotton when Treated Topically with Glyphosate at Various Growth Stages 1) Ten plants per plot were hand harvested on October 10, 1999 in Moultrie, GA. 2) Roundup Ultra applied at 1 qt/A broadcast over-the-top. Conventional plots treated with standard herbicide system. aa a b

Glyphosate Overtop After 4th Leaf Stage Can cause boll shed, delay maturity Salvage treatment only

Is Stem Absorption of Glyphosate Directed in RR Cotton a Concern? No noted concerns with precision applications in field trials Lab data from North Carolina, Georgia, and Mississippi? What about sloppy directed applications?

Cotton Yield After Various Glyphosate Applications. Moultrie, 2000.* *Glyphosate applied at 1.0 lb ai/A. PD = precision directed at cotyledons; SD = sloppy directed 33 to 40% up the plant. Standard system = Prowl + Cotoran fb Staple fb Caparol + MSMA. LSD = 55 Lint yield (Lb/A) Standard system Topical 1- & 4-lf Topical 4-lf PD 8- & 12-lf Topical 4-lf SD 8- & 12-lf a a a b b Topical 1-, 4-, & 12-lf

Directing Glyphosate in RR Cotton?  Precision PD or hooded sprayers

Directing Glyphosate in RR Cotton?  Precision PD or hooded sprayers  Direct spray to the base of the cotton plants

Directing Glyphosate in RR Cotton?  Precision PD or hooded sprayers  Direct spray to the base of the cotton plants  Contact of spray with cotton leaves should be avoided to the maximum extent possible

Directing Glyphosate in RR Cotton?  Precision PD or hooded sprayers  Direct spray to the base of the cotton plants  Contact of spray with cotton leaves should be avoided to the maximum extent possible  Place nozzles in low position directing a horizontal spray pattern under the cotton leaves to contact weeds in the row

Precision and Sloppy Applied Glyphosate

Breakout Session Objectives 1. New labels or uses 2. RR cotton tolerance to glyphosate 3. Managing weeds that are difficult to control in RR cotton

Weeds Difficult to Control by Glyphosate?

Cutleaf Eveningprimrose Response to Burndown Herbicides Treatment Rating GramoxoneF Gramoxone + DirexG GlyphosateF Glyphosate + DirexG Glyphosate + Harmony ExtraF-G Glyphosate + ClarityG Glyphosate + 2,4-DE

% control Cutleaf Eveningprimrose Control by Glyphosate and 2,4-D. Tifton, 2000.* *Roundup Ultra applied at 1 qt/A. Ratings 24 days after treatment. glyphosate2,4-D

Grams/plot Cutleaf Eveningprimrose Fresh Weights After Treating with Burndown Herbicides. Tifton, 2000.* *Fresh weights taken from 12 plants per plot. Roundup Ultra applied at 2 pt/A and 2,4-D at 1 pt/A.

2,4-D Burndown for Cotton (from fallow land section of labels)  No specific language concerning cotton  Do not plant any crop in treated fallow land until 3 months after treatment or until chemical has disappeared from soil

Current Recommendations -- 2,4-D Burndown for Cotton  1 pt/acre  Alone or mixed with glyphosate  Applied 45 days before planting  Research to date shows effectiveness and crop safety

Cotton Injury from 2.1 mls Per Acre of 2,4-D. Tifton, 2000.

Weeds Difficult to Control by Glyphosate?

USE A DNA HERBICIDE

Florida Pusley Control with Glyphosate and Glyphosate Tank Mixtures. Tifton, 2000.* % control 87 bc 92 ab 99 a 81 bc *Florida pusley 2 inches. Roundup UltraMAX applied at 1.25 pt; 2,4-D at 1 pt; Direx or Caparol at 1.5 pt.

Weeds Difficult to Control by Glyphosate?

Controlling Yellow and Purple Nutsedge? Nutsedge Control Programs: 1) 2 applications of glyphosate prior to 5th leaf followed by conventional chemistry including 2 lb ai MSMA directed 2) 1 application of glyphosate prior to 5th leaf followed by conventional chemistry including 2 lb ai MSMA directed 3) 2 applications of glyphosate 4) Zorial or Staple?????

Yellow and Purple Nutsedge Control by Glyphosate. Greenhouse. Glyphosate (lb) *Purple nutsedge controlled significantly greater than yellow nutsedge % control * * * LSD=10

Yellow and Purple Nutsedge Control by MSMA. Greenhouse. MSMA (lb) *Yellow nutsedge controlled significantly greater than purple nutsedge % control * * LSD=10

Weeds Difficult to Control by Glyphosate?

Mid-Season Morningglory Control by Glyphosate & Glyphosate/Staple Mixtures. Moultrie, Things to consider? 1. Morningglory size at time of application (5 inches here). 2. Will you post-direct with conventional chemistry or glyphosate? Glyphosate7389 Glyphosate + Staple9397 Pitted Smallflower morningglory

Glyphosate/Staple Tank Mixtures  DuPont label allows tank mix of 1.5 pt of Roundup Ultra plus 0.6 oz of Staple per acre broadcast  DuPont’s Staple Plus

Smallflower Morningglory Control by Glyphosate Alone and Mixed with Residual Herbicides; Attapulgus, % control% control Smallflower mg 4 to 5 inches; irrigated environment Roundup (2 pt/A), Bladex (1.5 pt/A), Caparol (1.5 pt/A), Direx (1.5 pt/A), Valor (2 oz/A) a b a a a

Weeds Difficult to Control by Glyphosate?

Asiatic Dayflower Control by Glyphosate & Glyphosate/Staple Mixtures. Grady Co., 2000.* % control *Dayflower 1 to 5 inches. Ratings 30 days after treatment. Roundup Ultra applied at 1.5 pt/A and Staple at 0.6 oz/A Glyphosate Glyphosate + Staple

Asiatic Dayflower Control by Glyphosate Mixtures at Layby. Grady Co., 2000.* % control LSD = 10 *Dayflower 1 to 5 inches. Ratings taken 30 days after directing in 8 to 10 inch cotton. Roundup Ultra, Caparol, and Direx applied at 1.5 pt/A. Cobra, Harvade, and Valor applied at 8 oz/A, 8 oz/A, and 2 oz/A, respectively

Asiatic Dayflower Control by Conventional Layby Herbicides. Grady Co., 2000.* % control LSD = *Dayflower 1 to 5 inches. Ratings taken 30 days after directing in 8 to 10 inch cotton. Bladex, Caparol, Cotoran, and Direx applied at 2 pt/A. Cobra, Harvade, Linex, MSMA, and Valor applied at 9.6 oz/A, 9 oz/A, 1.5 pt/A, 2.67 pt/A, and 2 oz/A, respectively.

Weeds Difficult to Control by Glyphosate?

Hemp Sesbania Control by Glyphosate. Tifton, 2000.* % control *Roundup Ultra applied at 2 pt/A. Experiment conducted under center irrigation. 3 inches7 inches 86 59

Breakout Session Objectives 1. New labels or uses 2. RR cotton tolerance to glyphosate 3. Managing weeds that are difficult to control in RR cotton 4. Glyphosate/tank mixes

Glyphosate + Tank Mix Partner 1. Increase morningglory control 2. Increase dayflower control 3. Residual weed control

Tank Mix Partners-Early Season 1. Staple

RR Cotton Injury from Glyphosate/Staple Mixtures

Cotton Injury from Glyphosate/Staple Combinations. Tifton, 2000.* *Glyphosate applied at 0.75 lb ai/A. Staple applied at 0.6 oz/A. Cotton 4-leaf at time of application. LSD = 4 % injury

Tank Mix Partners-Early Season 1. Staple* 2. Dual Magnum *Labeled tank mix with Roundup

Dual PRE Do Not Use Dual PRE on Georgia Soils

Tank Mix Partners-Early Season 1. Staple* 2. Dual Magnum 3. MSMA *Labeled tank mix with Roundup

Tank Mix Partners-Late Season 1. Diuron*6. Harvade* 2. Caparol7. MSMA 3. Cyanazine*8. Dual Magnum 4. Cotoran9. Prowl* 5. Cobra *Label supports tank mix with Roundup

Tank Mix Partners u Consider... weed species and sizes, economics, cotton stage, environment??

Tank Mix Partners  Consider... weed species and sizes, economics, cotton stage, environment?? DON’T FORGET ABOUT ANTAGONISM

Texas Panicum Control by Glyphosate Alone and in Mixture with Residual Herbicides. Ponder Farm, % control% control Texas panicum 6 to 9 inches; fair to dry environment Roundup (2 pt/A), Bladex (1.5 pt/A), Caparol (1.5 pt/A), Direx (1.5 pt/A), Valor (2 oz/A) a b ab a b

Palmer Amaranth Control by Glyphosate Alone and Mixed with Residual Herbicides. Attapulgus, % control% control Palmer amaranth 4 to 7 inches; irrigated environment Roundup (2 pt/A), Bladex (1.5 pt/A), Caparol (1.5 pt/A), Direx (1.5 pt/A), Valor (2 oz/A) ab a b b

Roundup Ultra (1 qt/A) + Caparol (1.5 pt/A)

 Glyphosate preferred for grasses and perennials  Otherwise, conventional chemistry preferred 1. Better morningglory and dayflower control 2. Residual weed control 3. Resistant management strategy 4. Avoid weed shifts 5. Reduce risk of boll shed Should I Direct Glyphosate in RR Cotton?

Breakout Session Objectives 1. New labels or uses 2. RR cotton tolerance to glyphosate 3. Managing weeds that are difficult to control in RR cotton 4. Glyphosate/tank mixes 5. Replacing Bladex

 Manufacturing ceased in 1999  Availability in 2001: 0, 40, 50?????  Bladex label: May not be sold or distributed after Sept. 30, May not be used after December 31, Do not apply more than 1.0 qt/A (1.0 lb ai/A). An enclosed cab is required. Cyanazine Availability

 Controls most troublesome broadleaf weeds when mixed with MSMA  Cotton tolerance acceptable if applied timely and precisely  Residual weed control for several weeks Cyanazine (Bladex, Cy-Pro)

 Other mid-season post-directed herbicide options: 1) Dual 2) Prowl 3) MSMA or DSMA 4) Cobra 5) Harvade 6) Goal 7) fluometuron (Cotoran, Meturon) 8) prometryn (Caparol, Cotton-Pro) 9) diuron (Karmex, Direx) Replace Cyanazine?

Smallflower Morningglory Control by Conventional Layby Herbicides. Turner Co., 2000.* % control LSD = *Morningglory 6 to 8 inches. Ratings taken 30 days after directing in 8 to 10 inch cotton. Bladex, Caparol, Cotoran, and Direx applied at 2 pt/A. Cobra, Harvade, Linex, MSMA, and Valor applied at 9.6 oz/A, 9 oz/A, 1.5 pt/A, 2.67 pt/A, and 2 oz/A, respectively.

Tropic Croton Control by Conventional Layby Herbicides. Turner Co., 2000.* % control *Croton 2 to 6 inches. Ratings taken 30 days after directing in 8 to 10 inch cotton. Bladex, Caparol, Cotoran, and Direx applied at 2 pt/A. Cobra, Harvade, Linex, MSMA, and Valor applied at 9.6 oz/A, 9 oz/A, 1.5 pt/A, 2.67 pt/A, and 2 oz/A, respectively LSD =

% control Sicklepod Control Comparison of Caparol and Direx. Tifton, 2000.* *All treatments included MSMA at 2 lb ai/A and 0.25% v/v NIS.

% control Smallflower Morningglory Control Comparison of Caparol and Direx. Tifton, 2000.* *All treatments included MSMA at 2 lb ai/A and 0.25% v/v NIS.

% control Palmer Amaranth Control Comparison of Caparol and Direx. Tifton, 2000.* *All treatments included MSMA at 2 lb ai/A and 0.25% v/v NIS.

% control Hemp Sesbania Control Comparison of Caparol and Direx. Tifton, 2000.* *All treatments included MSMA at 2 lb ai/A and 0.25% v/v NIS.

 Other mid-season post-directed herbicide options: prometryn (Caparol, Cotton-Pro) diuron (Karmex, Direx)  Weed control - most weeds?  Residual weed control - most weeds?  Carryover? experiments being conducted Replace Cyanazine?

Breakout Session Objectives 1. New labels or uses 2. RR cotton tolerance to glyphosate 3. Managing weeds that are difficult to control in RR cotton 4. Glyphosate/tank mixes 5. Replacing Bladex 6. Cadre carryover

Cadre carryoverNon-treated

Cadre Carryover  11 cultivars compared for tolerance including Delta Pearl, DP 33 B, DP 5415, DP 458, ST 4892, STX 9903, BXN 47, FM 989, AP 6101, GA 161, SG ) no difference in plant stand 2) visual injury similar among cultivars 3) vigor reductions similar among cultivars 4) plant height reductions similar among cultivars

Breakout Session Objectives 1. New labels or uses 2. RR cotton tolerance to glyphosate 3. Managing weeds that are difficult to control in RR cotton 4. Glyphosate/tank mixes 5. Replacing Bladex 6. Cadre carryover 7. DNA application timing in strip-till

Large Crabgrass Control by Various Application Methods of Prowl. Rocky Mount, NC * % control% control 14 b 66 a ACY Early pre- plant Before strip- tillage 79 a After planting *Roundup applied early pre-plant and at planting. Ratings taken 16 days after planting. EPP applied 21 d prior to planting.

Slender Amaranth Control by Various Application Methods of Prowl. Clayton, NC * % control% control 40 c 66 b *Roundup applied early pre-plant and at planting. Ratings taken 28 days after planting. EPP applied 21 d prior to planting. ACY Early pre- plant After planting 97 a Before strip- tillage

Breakout Session Objectives 1. New labels or uses 2. RR cotton tolerance to glyphosate 3. Managing weeds that are difficult to control in RR cotton 4. Glyphosate/tank mixes 5. Replacing Bladex 6. Cadre carryover 7. DNA application timing in strip-till 8. Layby applications in liquid N

Cotton Injury from Directed Herbicides in Water and Water/N Mixtures. Tifton, 2000.* *All treatments included MSMA at 2 lb ai/A. N mixtures were half water and half 30% N. Ratings taken 3 wk after treatment. Cotton 8 to 10 inches at time of application. LSD = 7 % injury

Things to Come 1. Valor 2. Liberty Link Cotton 3. CGA Enhanced Roundup Ready Cotton