COTTON WEED MANAGEMENT

Transcription

1 TABLE 1. Effectiveness of selected cotton herbicides four weeks after application. hophornbeam copperleaf smellmellon bermudagrass rhizome johnsongrass seedling Johnson grass annual grasses yellow nutsedge prickly sida pigweed morningglory hemp sesbania sicklepod PREEMERGENCE HERBICIDES: Command 3ME Cotoran, Meturon or Fluometuron S-metolachlor/metolachlor (all formulations) Diuron Treflan or Prowl Solicam DF Treflan or Prowl + Cotoran, Treflan, or Prowl + Diuron Treflan or Prowl + Solicam DF Staple LX + Cotoran POSTEMERGENCE HERBICIDES: Aim/ET Aim/ET + MSMA Aim/ET + glyphosate Assure II Cobra + MSMA Cotoran, Meturon or Fluometuron Caparol or Cotton-Pro Caparol or Cotton-Pro + MSMA Cotoran + MSMA Envoke Fusilade DX glyphosate 1, glyphosate 1,2 + Warrant Goal + MSMA Liberty 280 SL Liberty 280 SL 3 + Dual Magnum Liberty 280 SL 3 + Staple LX diuron diuron + MSMA

2 TABLE 1 continued: Effectiveness of selected cotton herbicides four weeks after application. hophornbeam copperleaf smellmellon bermudagrass rhizome johnsongrass seedling Johnson grass annual grasses nutsedge prickly sida pigweed morningglory hemp sesbania Sicklepod POSTEMERGENCE HERBICIDES continued: Linex + MSMA Poast Plus Select Max/other clethodim formulations Sequence Staple LX Staple LX + glyphosate Suprend Valor For use only in Roundup Ready and GlyTol/Liberty Link varieties. Glyphosate-resistant Italian ryegrass, johnsongrass, Palmer amaranth and tall waterhemp have been documented in Louisiana. 2 See Appendix A for various glyphosate products. 3 For use only in Liberty Link and GlyTol/Liberty Link varieties.

3 PREPLANT 1 : lb/a Dual pt/a Italian ryegrass Apply to prepared seedbeds between September 1 and December 1. Best control is generally observed from late October to mid-november. Will not control emerged ryegrass. Mix with paraquat to control emerged ryegrass. Incorporation will be beneficial if an activating rainfall is not received soon after application. Don t incorporate deeper than 2-3 inches. The maximum combined fall and spring metolachlor rate is 2.54 pt/a lb/a 1 2 oz/a Residual control of pigweed and control and/or partial control of other broadleaf weeds. Mix with other herbicides to burndown existing vegetation. Apply 30 days before planting. Do not plant until at least 1 inch of rainfall or overhead irrigation has been received following application lb/a Reflex 2 1 pt/a Residual control of pigweed and control and/or partial control of other broadleaf weeds, sedges and grasses. Mix with other herbicides to burndown existing vegetation. Apply days before planting. Do not plant until at least 1/2 inch of rainfall or overhead irrigation has been received following the application. Plant at least 0.75 inches deep. Do not use on light/coarse textured soils. Cotton plants may exhibit some crinkling or spotting on foliage or stunting, but plants normally outgrow these effects. PREPLANT INCORPORATED: lb/a Prowl 3.3 EC/Pendimax pt/a on coarse soil pt/a on medium soil pt/a on heavy soil Most annual grasses, seedling johnsongrass and fair control of some broadleaf weeds Apply before planting and incorporate up to 1/2 inch deeper than the seed is planted. Incorporation will be necessary if sufficient rainfall is not received within seven days. Prowl 1-2 pt/a on coarse soil 2 pt/a on medium soil 3 pt/a on heavy soil lb/a Treflan, Trifluralin, and other 4L pt/a on coarse soil pt/a on medium soil 3 pt/a on heavy soil Most annual grasses, johnsongrass from seed and fair control of some broadleaf weeds Apply prior to or after planting. Incorporate up to 1/2 inch deeper than seed if applied preplant or almost to seed if applied after planting.

4 PREEMERGENCE: lb/a Command pt/a Most annual grasses and good control of prickly sida, wild poinsettia, spurred anoda, velvetleaf and itchgrass Apply before or after planting. Requires the use of disulfoton or phorate applied in furrow to protect cotton from injury. Read and follow label instructions concerning application conditions and buffer zones to reduce nontarget drift injury. Excessive rainfall at lb/a 1.5 qt/a Annual grasses and small-seeded broadleaves planting may lead to injury. Consult label for rate range considering soil type and O.M. content. Can be applied from emergence through the 4-leaf stage, with optimum being two- to three-leaf. Emerged weeds are not controlled and require addition of a labeled postemergence herbicide such as glyphosate or glufosinate. Please see label for appropriate tank mix partners and related information. metolachlor lb/a S-metolachlor lb/a lb/a Parallel pt/a on coarse soil pt/a on medium soil pt/a on heavy soil Dual Magnum, Dual II pt/a on medium soil 1.33 pt/a on heavy soil Cotoran 80WP, Meturon 80DF, Fluometuron 1.0 lb/a on light soil 1.5 lb/a on medium soil 2.5 lb/a on heavy soil Most annual grasses and small seeded broadleaf weeds Most annual grasses and smallseeded broadleaf weeds Most small-seeded annual grasses and broadleaf weeds Apply after planting before weeds emerge. May also be applied before planting or preplant incorporated. Cotton should be planted 1.5 inches deeper than incorporated zone. Apply after planting before weeds emerge. May also be applied before planting. Cotton should be planted 1.5 inches deeper than incorporated zone. Apply at planting. Cover seed at least 1/2 inch deep. Apply to soil surface behind press wheel lb/a Cotoran, Meturon 0.8 qt/a on coarse soil 1.2 qt/a on medium soil 2.0 qt/a on heavy soil Prowl 3.3, pt/a on coarse soil pt/a on medium soil pt/a on heavy soil Annual grasses and small-seeded broadleaf weeds Apply at planting. Rainfall required within seven days for activation. Can be used in no-till or reduced-till cotton where incorporation cannot be used. Prowl 1-2 pt/a on coarse soil 2 pt/a on medium soil 3 pt/a on heavy soil

5 PREEMERGENCE continued: oz/a lb./a Staple fl. oz./a + flumeturon as above Better control of yellow nutsedge and certain broadleaf weeds Apply at planting. Best control is achieved with sequential postemergence Staple LX treatments. Follow lb/a Solicam 1.25 lb/a on light soil 1.9 lb/a on medium soil 2.5 lb/a on heavy soil Most small-seeded annual grasses and broadleaf weeds. Fair control of nutsedge. label directions. Apply at planting. Can be applied up to 30 days before planting. Can be incorporated before planting at the same rate as the surface application or split ½ PPI and ½ PRE. fluridone lb/a lb/a fluridone lb/a lb/a POSTEMERGENCE: lb/a lb/a lb/a fenoxaprop-ethyl lb/a Brake 32 oz/a on light soil 32 to 42 oz/a on medium and heavy soil Annual grasses and broadleaves Do not apply more than 42 oz/a per year. Requires adequate rainfall or irrigation following application for optimum results. Brake oz/a Annual grasses and broadleaves Do not apply more than 21 oz/a per year. Requires adequate rainfall or irrigation following application for optimum results. Apply oz/a preemergence or up to 14 d prior to planting. Apply oz/a up to 14 d prior to planting. Assure 5-10 oz/a Apply with 1 qt/100 gal or 1 gal/100 gal oz/a. Apply with 1 qt/100 gal Fusilade pt/a Apply with 1 qt/100 gal or 1 gal/100 gal. 10 oz/a. Apply with 1 qt/100 gal or 1 gal/100 gal. Annual and perennial grasses Broadleaves (including sicklepod) and sedges; weak on prickly sida Annual and perennial grasses Same as above Apply before grasses exceed height for treatment. Use 5-8 oz/a on annual grasses and 10 oz/a on perennial grasses. Apply after cotton reaches the 5-true-leaf stage. Do not apply to cotton that is stressed. Do not tank-mix with any EC formulated product as increased injury may be observed. Consult label for approved tank-mixes. Do not tankmix with grass herbicides as grass control will be reduced. Not labeled for aerial application. Apply before annual grasses reach 4 inches and johnsongrass reaches 2 feet. Use the highest rate on bermudagrass with runners. Activity may be reduced if mixed with other herbicides. Use lowest range of rates for shatter cane and seedling johnsongrass. Same as above

6 POSTEMERGENCE continued: lb/a Poast pt/a Annual and perennial grasses lb/a lb/a glyphosate lb/a glyphosate lb/a + S- metolachlor lb/a Apply with 1 qt/100 gal or 1 gal/100 gal. Staple fl. oz/a Apply with 1 qt/100 gal Select oz./a 2 lb/gal 6-16 oz/a Apply with 1 qt/100 gal or 1 gal/100 gal Roundup 22 oz/a Touchdown 24 oz/a 4L 32 oz/a 4 L oz/a + Dual pt/a or Sequence pt/a Pigweed, cocklebur, morningglory, prickly sida and other broadleaf weeds Annual and perennial grasses Most broadleaf weeds and grasses Most broadleaf weeds and grasses Apply at 1.5 pt/a before annual grasses reach 4 inches and johnsongrass reaches 2 feet. Use 2.25 pt/a to control bermudagrass with 4-6 inch runners. Application to larger grasses or grasses under stress may result in reduced control. Activity may be reduced if mixed with other herbicides. Apply when weeds are small and actively growing. Temporary cotton injury seen as chlorosis (yellowing) may occur following application. Weak on sicklepod. Can be banded. Spray grade nitrogen fertilizer or ammonium sulfate may improve weed control. Refer to label. Application same as above. Refer to label for rate for specific grass species. Addition of a spray-grade nitrogen fertilizer or ammonium sulfate may further improve weed control. Refer to label. USE ON ROUNDUP READY FLEX, GLYTOL/LIBERTY LINK, ENLIST, AND XTEND VARIETIES ONLY: No restriction on cotton size. Larger cotton may interfere with spray coverage, resulting in reduced weed control. Allowing weeds to compete with cotton for an extended period may reduce cotton yield. Can be mixed with insecticides and PGRs. Air induction nozzles may reduce insecticide efficacy. Consult label for maximum application rates. Consult label for approved formulations. Do not add surfactants or products with surfactants. USE ON ROUNDUP READY FLEX, GLYTOL/LIBERTY LINK, ENLIST, AND XTEND VARIETIES ONLY: No restriction on cotton size. See other cautions above. DO NOT mix with Staple LX. Can be applied in first or second overtop application to provide residual control. Do not use additional surfactant. Check label for approved products. Don t exceed 3.5 pt/a/season

7 glyphosate Most broadleaf weeds and grasses lb/a Glyphosate (4 lb/gal formulations) + Staple 1.0 qt/a oz/a POSTEMERGENCE continued: lb/a Liberty oz/a Broadleaves and grasses. Consult label for rates and size restrictions lb/a lb/a Liberty oz/a + Staple oz/a Most broadleaf weeds and grasses USE ON ROUNDUP READY FLEX, GLYTOL/LIBERTY LINK, ENLIST, AND XTEND VARIETIES ONLY: No restriction on cotton size. See comments for glyphosate and pyrithiobac tankmix. DO NOT mix with any metolachlor product. DO NOT exceed a total of 2 oz pyrithiobac/year. LIBERTY-LINK, GLYTOL/LIBERTY LINK, ENLIST, AND XTEND VARIETIES ONLY: Apply from cotton emergence to early bloom. Time applications to weed size, not crop stage. Weak on sedges, large goosegrass and signalgrass. Pigweeds may not be effectively controlled if larger than 3-4 inches. Prowl, Dual Magnum, or Staple LX PRE may aid in pigweed control in this system. Do not apply more than 87 oz/a/season. 70 days to harvest. Do not use air induction spray tips. Apply in a minimum of 15 GPA. LIBERTY-LINK, GLYTOL/LIBERTY LINK, ENLIST, AND XTEND VARIETIES ONLY: Broadcast to improve pigweed control. Maximum use rate for pyrithiobac is 2 oz/year lb/a + metolachlor lb/a Liberty oz/a + Dual pt/a Broadleaves and grasses. Consult label for rates and size restrictions 0.78 lb/a Liberty 43 oz/a Salvage situation if broadleaf and grass weed size is large LIBERTY-LINK, GLYTOL/LIBERTY LINK, ENLIST, AND XTEND VARIETIES ONLY: See above comments. Apply in a minimum of 15 GPA. Do not use air induction spray tips. DO NOT mix with Staple LX. Apply at cotton emergence to early bloom. Time applications to weed size, not crop stage. LIBERTY-LINK, GLYTOL/LIBERTY LINK, ENLIST, AND XTEND VARIETIES ONLY: See note above. Do not apply more than 87 oz/a/season. 0.5 lb/a 12.5 oz/a OR 22 oz/a OR 22 oz/a Broadleaf weeds. Expect poor control of grass weeds, hophornbeam copperleaf, and prickly sida if dicamba is applied alone. FOR USE IN XTEND VARIETIES ONLY. Only Engenia, FeXapan, and XtendiMax are labeled for use in Xtend cotton. Federal and state labels contain numerous restrictions. See label for further information. All labeled dicamba formulation can be tank-mixed with glyphosate or other herbicides to broaden the weed spectrum. Please see company websites for list of products that can be legally tank-mixed. See Herbicide-Tolerant Cotton Varieties on last page of this section for further information.

8 POSTEMERGENCE continued: 2,4-D lb/a lb/a Enlist oz/a Grass and broadleaf weeds. FOR USE IN ENLIST VARIETIES ONLY. Only labeled for use in Enlist cotton. Federal and state labels contain numerous restrictions. See label for further information. Enlist Duo can be tank-mixed with other herbicides to broaden the weed spectrum. Please see company website for list of products that can be legally tankmixed. See Herbicide-Tolerant Cotton Varieties on last page of this section for further information. 2,4-D lb/a Enlist oz/a Broadleaf weeds FOR USE IN ENLIST VARIETIES ONLY. Only labeled for use in Enlist cotton. Federal and state labels contain numerous restrictions. See label for further information. Enlist One can be tank-mixed with other herbicides to broaden the weed spectrum. Please see company website for list of products that can be legally tankmixed. See Herbicide-Tolerant Cotton Varieties on last page of this section for further information. DIRECTED POSTEMERGENCE: The following herbicides can be applied singly with a surfactant or in combination MSMA as a directed spray. MSMA use in cotton is limited to two applications per year not to exceed 2 lbs/a each. A 50-foot buffer zone is required around permanent water bodies. Glyphosate 4 and Liberty 280 can also be tank mixed with many of the following products according to label directions. Use glyphosate and Liberty 280 SL with the appropriate herbicide resistant cotton variety lb/a Aim oz/a. Broadleaf weeds Apply after cotton is 12 inches tall. Avoid contact with cotton above the bark layer. Does not control grasses. Do not apply more than 3.25 oz/a/year as a layby or post-direct application. May improve morningglory and hemp sesbania control with glyphosate. pyraflufen lb/a lb/a 0.5 to 2 oz/a. Apply with 1 qt/100gal or 1 gal/100 gal. Cotoran/Meturon, Fluometuron lb/a Cotoran/Meturon qt/a. Broadleaf weeds Annual seedling grasses and broadleaf weeds Apply only with hooded spray equipment to plants with less than 3 inch stem bark. May be applied with postdirected equipment to cotton 18 inches in height and with at least 3 inches stem bark. Apply after cotton is 3 inches tall. Two postapplications can be made providing fluometuron was not used preemergemce-. Make one early postapplication if fluometuron was used preemergence. Apply with 1qt/100 gal or

9 DIRECTED POSTEMERGENCE continued: 0.19 lb/a lb/a Cobra oz/a. Caparol lb/a Caparol qt/a. Broadleaf weeds Annual seedling grassy and broadleaf weeds Apply after cotton is 8 inches tall. Apply as a directed spray only. Apply after cotton is 3 inches tall. Directed spray only. If MSMA is added, do not apply after first bloom lb/a lb/a lbs/a lb/a lb/a lb/a Direx pt/a Karmex oz/a. Goal pt/a Reflex pt/a Linex pt/a lb/a. 1gal/100 gal Annual seedling grasses and broadleaf weeds less than 3 inches tall and actively growing Annual seedling grassy and broadleaf weeds Broadleaf weeds Annual seedling grassy and broadleaf weeds Select grasses and many broadleaves. Good on sicklepod. Apply after cotton is 6 inches tall and actively growing. Directed spray only. If MSMA is added, do not apply after first bloom. Apply after cotton is 8 inches tall. Apply as a directed spray. Use low pressure and large droplets. Avoid contact with cotton. Apply after cotton is at least 6 inches tall. May be used as layby or under hooded sprayers. Do not apply Reflex later than 70 days before harvest. Do not apply more than 1.5 pints per acre of Reflex in any year. Avoid spray contact with cotton leaves. May be tank mixed with other products, especially grass herbicides to provide broad spectrum weed control. Apply after cotton is 8 inches tall. Apply as a directed spray only. Apply after cotton is at least 6 inches tall. May be tankmixed with diuron, MSMA, glyphosate or Cobra for improved control of existing grasses.

10 LAYBY (one application): lb/a Karmex lb/a on light soil 1.0 lb/a on medium soil 1.5 lb/a on heavy soil Direx 1.5 pt/a on medium soil 2.0 pt/a on heavy soil Most small-seeded annual grasses and broadleaf weeds. Weak on signalgrass and browntop millet. Apply when cotton is at least 15 inches tall to a clean field. Apply with four nozzles per row or one flooding nozzle adjusted to completely cover the row but to keep spray off the cotton plants. Actively growing weeds up to 3 inches tall can be controlled by adding surfactant or COC lb/a lb/a Linex 1 pt/a on light soil 2 pt/a on medium soil 3 pt/a on heavy soil 1.0 lb/a Cotoran, Meturon, Fluometuron lb/a lb/a SPOT TREATMENT: 1.0 lb/100 gal water Cotoran or Meturon 1 qt/a 1-2 oz/a Apply with 1qt/100gal. Fusilade 2 qt/100 gal water. 1 gal/100 gal Caparol lb/a on light soil 1.75 lb/a on medium soil 2.0 lb/a on heavy soil Caparol 4L, 2.4 pt/a on light soil 2.8 pt/a on medium soil 3.2 pt/a on heavy soil Most small-seeded annual grasses and broadleaf weeds Most annual grasses with fair control of broadleaf weeds Pigweeds, prickly sida, copperleaf, morninglory, sicklepod, cocklebur Johnsongrass Most small-seeded annual grasses and broadleaf weeds Apply when cotton is at least 15 inches tall to a clean field. (Same remarks as for single application of diuron for layby.) Same remarks as for single application of diuron for layby. Use this treatment if fall seeded crops will be grown. Apply when cotton is at least 15 inches tall to a clean field. (Same remarks as for single application of diuron for lay-by.) Apply post-directed when cotton is at least 16 inches tall and has at least 2 inches of bark. Do not apply more than 2 oz/a/application or more than 4 oz/a/season. Do not use crop oil concentrate, organo-silicant surfactants, or methylated seed oils. Valor will control emerged weeds given sufficient spray coverage. Good residual control of broadleaves with suppression of grasses.

11 lb/100 gal Select oz/100 gal Same as above Same as above. Apply to rapidly growing grass 1-2 feet water water tall. Spray to wet. 1.0 lb/100 gal of water glyphosate 4-8 lb/100 gal of water ROPE WICK APPLICATIONS: glyphosate 2.0 lb/1.0 gal of water 1 gal/100 gal Poast Plus at 1.0 gal/100 gal water. Apply with 1 qt/100 gal Glyphosate (4 lb/gal gal/ 100 gal of water Johnsongrass Grasses or broadleaf weeds Glyphosate (4 lb/gal 0.5 gal/1.0 gal of water Same as above Same as above. Apply to rapidly growing grass 1-2 feet tall. Spray to wet. Apply to rapidly growing weeds. Thoroughly wet the weed foliage and keep spray off of the crop plants. May be used as a salvage application after 20 percent cracked bolls. johnsongrass 1 Refer to the burndown section of this guide for suggestions on managing cool-season weeds. 2 Metolachlor contains a 1:1 ratio of two metolachlor isomers (-R and S). S-metolachlor contains only the S isomer. The S isomer has greater herbicidal activity than the R isomer. On the herbicide label, the R isomer is denoted by metolachlor while the S isomer is denoted by acetamide (s). Alternatively, if the trade names Bicep or Dual include the word Magnum, the S isomer is an active ingredient. If the trade name does not include Magnum, the metolachlor R:-S isomer ratio is 1:1. 3 See Appendix A for glyphosate products and their surfactant requirements. HERBICIDE-TOLERANT VARIETIES Roundup Ready Flex Cotton. These varieties are tolerant to overtop applications of glyphosate. The initial application of glyphosate should be made at 0.7 to 1.0 lb/a when weeds are less than 4-inches tall. If the first application is made to weeds 5-12 inches tall, increase the rate of glyphosate to 1.5 lb/a. Numerous formulations of glyphosate are available for use and are shown in Appendix A; therefore, rates may differ depending upon glyphosate formulation used. Additionally, ensure that the formulation is labeled for use in Roundup Ready Flex cotton. Consult the product label for use requirements. Remember that the longer the weeds remain in the field, the larger they become and longer they compete with the cotton. Since some morningglories, hemp sesbania, yellow and purple nutsedge and dayflower are not controlled with one application, two applications of glyphosate often are needed. Sequential treatments may be needed, depending upon weed pressure, growing conditions and other factors. If applying glyphosate by air, be extremely careful to prevent off-site target movement. In addition, weeds resistant to glyphosate have been identified in Louisiana; therefore, programs with multiple herbicidal modes of action applied as residual (preemergence and postemergence) in conjunction with glyphosate is a must. Liberty Link Cotton. These varieties are tolerant to overtop applications of Liberty (glufosinate). The initial application of Liberty should be made at 32 to 43 oz product/a, 7-10 days after cotton emergence. A sequential application of Liberty should follow days later or to 2- to 4-inch weeds. A maximum of 72 oz product/a/year can be applied.. Liberty should provide good control of most broadleaf weeds, but is weak on grass weeds. For acceptable grass weed control, Liberty should be applied to grasses less than 3 inches tall. The Liberty Link cotton weed control system works very well with a residual herbicide that provides grass control. Metolachlor or S-metolachlor containing products may be tank-mixed with Liberty to provide residual control of some small-seeded broadleaf and grass weeds. If Liberty Link cotton is planted in an area with known large grassy weed populations, a graminicide such Select Max, Fusilade, etc. should be budgeted to control late-season grass problems. If Liberty Link cotton is planted in an area

12 with known herbicide-resistant weeds (ex. glyphosate-resistant Palmer amaranth or waterhemp), addition of residual herbicides applied preemergence and postemergence must be included in the weed management program. In addition, target 1- to 2-inch Palmer amaranth or waterhemp with any Liberty application for maximum control. GlyTol/Liberty Link Cotton. These varieties are tolerant to glyphosate and glufosinate. Information presented above for Roundup Ready and Liberty Link cotton apply. LSU AgCenter data indicates that tank-mixing glyphosate and glufosinate at labeled rates does not negatively influence control of numerous grass and broadleaf weeds and can be safely applied to GlyTol/Liberty Link cotton. If GlyTol/Liberty Link cotton is planted in an area with known herbicide-resistant weeds (ex. glyphosate-resistant Palmer amaranth or waterhemp), addition of residual herbicides applied preemergence and postemergence must be included in the weed management program. In addition, target 1- to 2-inch Palmer amaranth or waterhemp with any glufosinate application for maximum control. Xtend Cotton. These varieties are tolerant to dicamba, glyphosate, and glufosinate. The initial application of dicamba plus glyphosate should be made when weeds are no more than 3-inches tall. Dicamba cannot be tank-mixed with glufosinate. LSU AgCenter data indicates that weed management programs in Xtend cotton should contain residual herbicides applied preemergence and early-postemergence to ensure season-long weed control. BASF, DuPont, and Bayer provide websites listing which herbicides can be legally tank-mixed with their dicamba product. Implementation of a weed management program containing residual herbicides preemergence and postemergence is critical if dicamba will be applied for control of herbicideresistant weeds (ex. glyphosate-resistant Palmer amaranth or waterhemp) as dicamba applied alone or when tank-mixed with glyphosate will not provide season-long control of herbicide-resistant weeds. Enlist Cotton. These varieties are tolerant to 2,4-D, glyphosate, and glufosinate. The initial application of Enlist Duo (2,4-D choline plus glyphosate) should be made when weeds are no more than 4-inches tall. Enlist One (2,4-D choline only) can be tank-mixed with glufosinate. LSU AgCenter data indicates that Enlist One plus glufosinate provides good to excellent control of numerous broadleaf weeds whether they are resistant to glyphosate or not. Also, LSU AgCenter data indicates that weed management programs in Enlist cotton should contain residual herbicides applied preemergence and early-postemergence to ensure season-long weed control. However, not all herbicides can be legally tank-mixed with Enlist Duo or Enlist One. Dow provides a website listing which herbicides can be legally tank-mixed with both herbicides. Implementation of a weed management program containing residual herbicides preemergence and postemergence is critical if 2,4-D choline will be applied for control of herbicide-resistant weeds (ex. glyphosate-resistant Palmer amaranth or waterhemp) as 2,4-D applied alone (Enlist One) or when with glyphosate (Enlist Duo) will not provide season-long control of herbicide-resistant weeds.