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For foliar activity, add MSO (1% v/v or 1 gallon per 100 gallons or minimum of 1 pt/A with low volume applications) and either AMS (8.5-17 lb per 100 gallons) or UAN (1.25-2.5% v/v or 1.25-2.5 gallons per 100 gallons). Minimum carrier volume is 5 gpa for ground applications or 3 gpa for aerial applications. If foliar activity is desired, the minimum carrier volume is 10 gpa (15-20 gpa is suggested) for ground applications or 5 gpa for aerial applications. May be impregnated onto dry granular fertilizer.
More flexible rotation options than atrazine. Crop rotation restriction is 6 months or less for most crops.
PPS or PPI. For applications up to 14 days prior to corn planting. May also apply up to 30 days prior to planting, but this is not recommended for coarse soils.
PRE. Do not apply after corn begins to emerge.
10-16 fl oz per acre. Apply 10 fl oz/A on coarse soils or up to 16 fl oz/A on fine textured soils. The 13 oz rate for mediumtextured soils is equivalent to 2.6 fl oz/A Sharpen + 10.8 fl oz/A Outlook. Intended for use in two-pass programs that will include a postemergence application. Provides foliar and residual control of several annual broadleaf weed species and grass species such as foxtail, crabgrass, and barnyardgrass. After application, at least 0.5 inches of rain is needed to activate the herbicide. Crop injury may occur during stressful conditions such as extreme hot or cold conditions, excessive moisture or drought, high soil pH, or disease injury. Special 24c label for SD prohibits application on specific soil types that have sand 0-12 inches below the soil surface, O.M. is 3% or less, and the water table is less than 30 feet below the soil surface.
For foliar activity, add either MSO (1% v/v or 1 gallon per 100 gallons) or COC (1% v/v) and either AMS (8.5-17 lb per 100 gallons) or UAN (1.25-2.5% v/v or 1.25-2.5 gallons per 100 gallons). Minimum carrier volume is 3 gpa for ground or aerial applications. More flexible rotation options than atrazine. Rotation intervals for soybeans range from 0-4 months after application depending on rate applied, soil texture, and organic matter. If only 5 fl oz/A is applied, soybeans may be planted any time on coarse soils with 2% O.M. or on fine texture soils. Otherwise, soybean rotation intervals are 1 month or greater. Wheat may be planted 4 months after application and any crop may be planted one year after application.
PPS. For applications up to 14 days prior to corn planting. May also apply up to 30 days prior to planting, but this is not recommended for coarse soils.
PRE. Do not apply after corn begins to emerge.
Supplemental label for burndown applications 14-30 days prior to corn planting. When tank mixed with glyphosate, Valor provides residual and foliar control of wild buckwheat, pigweeds, waterhemp, lambsquarters, kochia, mustards, and others. May be tank mixed with 2,4-D to provide control of winter annual weed species such as marestail/horseweed. Add NIS (0.5% v/v or 2 qt per 100 gallons spray solution) plus AMS (17 lb per 100 gallons spray solution) with glyphosate mixes or COC (1 pt/A) with 2,4-D mixes.
6 www.iGrow.org PPS FALL. Apply after November 15 or after the ground is less than 50o F.
PPS SPRING. Apply at least 14 days prior to corn planting. At least 1 inch rain or irrigation should occur after application but prior to corn planting.
MICRO-TECH (alachlor) Site of Action: 15 2-4 qt Micro-Tech 4L (2-4 lb ai) Very good to excellent control of several annual grasses. Fair control of pigweed and lambsquarters with high rates. Consistent on annual grasses. Very good crop tolerance. Rates of 2.5-3 qt Micro-Tech or 16-20 lb 15G (broadcast) per acre have been satisfactory in most SDSU tests. Rates of 3-4 qt per acre are suggested for severe weed infestations or for yellow nutsedge, or when planting into heavy residue.
Minimum carrier is 10 gpa for ground or 3 gpa for air. Granule and spray formulations appear equally effective. Micro-Tech is a microencapsulated formulation containing 4 lb per gallon. No carryover.
EPPS. Apply 60% of the total amount as the first part of a split application if treating 30-45 days before planting and the remainder at planting.
SPPI. Incorporate into the top 2 inches within 7 days of planting. Flextine harrow is not satisfactory. Better results than preemergence when rain is very limited, but slightly less control than a preemergence application with adequate rain. Heavy rain reduces results.
Proper incorporation may be difficult with trashy, lumpy seedbed.
PRE. Requires 0.5-0.75 inch rain within one week after application.
EPOST. Apply from crop emergence to 5 inches. Emerged weeds are not controlled. Not a planned weed program. Liquid fertilizer carrier may cause severe injury.
Premixes with atrazine are listed below. Labeling also includes preemergence mixes with Banvel or Marksman or with glyphosate or Gramoxone for burndown.
MICRO-TECH + ATRAZINE EPP, SPPI, PRE, EPOST. Mix 1.5-4 qt Micro-Tech + 1-2 lb ai atrazine. Rates of 2-2.5 qt Micro-Tech + atrazine at 1 qt of 4L or 1.1 lb of 90DF per acre have been used in most SDSU tests. Postemergence must be applied before corn is 5 inches and grass is less than 2-leaf stage.
EPP, SPPI, PRE, EPOST. Use 2.5-4.5 qt Lariat or Bullet premix per acre. Lariat and Bullet contain 2.5 lb alachlor + 1.5 lb ai atrazine per gallon. Refer to tank-mix section.
METOLACHLOR PRODUCTS Site of Action: 15 ($13.50-33.30) DUAL II MAGNUM, BRAWL, CINCH, CHARGER BASIC, MEDAL (s-metolachlor) 1-2 pt Dual II Magnum, Cinch, or Medal II 7.64L or 6-12 lb Dual II G-Magnum 16G (0.95-1.9 lb ai) 1-2 pt Charger Basic, Brawl, or Medal 7.62L Very good to excellent control of several annual grasses. Fair control of pigweed with high rates. Weak on lambsquarters. Consistent on annual grasses when rainfall or soil moisture requirements are met. Rates of 1.67-2 pt Dual II Magnum or Cinch or 10-12 lb 16G per acre (broadcast) have been satisfactory in most SDSU tests. Labeling includes higher rates for special grass problems. Very good crop tolerance. Minimum carrier is 10 gpa for ground and 2 gpa for air. No carryover. Labeled for field, silage, and sweet corn.
Dual products designated as “II” contain a crop protectant. Products designed “Magnum” contain the resolved form of metolachlor (s-metolachlor) and product rates were adjusted.
EPPS. Apply 2/3 of the total as the first part of a split application if treating 30-45 days before planting and apply the remainder at planting. Applications less than 30 days before planting may be as a split or single application. Split application usually preferred if more than 14 days before planting. Do not apply more than 2 weeks before planting on sandy soil.
SPPI. Incorporate into top 2 inches within 14 days. Better results than preemergence when rain is very limited, but gives slightly less control than preemergence with adequate rain. May be more consistent in low rainfall areas. Heavy rain reduces effectiveness.
Proper incorporation may be difficult with trashy, lumpy seedbed. Deeper incorporation reduces control. Use maximum rate for soil type.
PRE. Requires 0.5-0.75 inch rain within one week after application.
POST. Apply postemerge until corn reaches 40 inches. Less consistent. Use with a tank-mix partner that controls emerged weeds.
STALWART C or PARALLEL (metolachlor) 1-2 pt Stalwart C or Parallel 7.8L (0.98-2 lb ai) Products contain metolachlor. EPA has limited the rate to the same amount of product as for Dual II Magnum containing s-metolachlor.
Higher rates are included for certain grassy weed problems. Apply as for s-metolachlor above.
Intended to control emerged weeds and provide residual control of several annual grass weed species. Rates vary from 2.5-4 pt/A depending on weed height at the time of application. Each pint of Sequence contains the equivalent of 0.4 pt Dual Magnum.
PPS and PRE. Apply to Roundup Ready or non-RR corn. Do not apply more than 3.5 pt/A on coarse soils or 4 pt/A on medium or fine textured soils.
EPOST. Apply only to glyphosate (e.g. Roundup Ready) corn from emergence until 30 inches tall. Do not exceed 2.5 pt/A in a single application or a total of 5 pt/A per season. Do not exceed 1.5 lb ae/A glyphosate per season (each pint of Sequence contains approximately 0.3 lb ae). Do not apply to corn stressed from weather, insects, disease, or cultivation injury. Do not graze or feed treated forage until 30 days after application. May be tank mixed with atrazine, dicamba, 2,4-D,Callisto, or other (see label).
EXPERT (s-metolachor + glyphosate + atrazine) ($21.45-32.15) Intended to provide control of emerged weeds and residual control of several broadleaf and grass weed species. Rate is 2.5-3.75 qt/A. Rates vary based on soil texture and organic matter. Adding AMS (2% by weight or 17 lb per 100 gallons spray solution) may improve weed control during adverse conditions. Expert at 3 qt/A contains the equivalent active ingredient as 1.6 qt/A atrazine 4L,
1.4 pt/A Dual II Magnum, and 23 oz/A Touchdown Total (glyphosate). Minimum carrier is 10 gpa (use 20 gpa in dense canopies) for ground applications. Do not apply with aerial equipment.
Expert may be tank mixed with Dual II Magnum (s-metolachlor), atrazine, Princep (simazine), glyphosate, Python (flumetsulam), Hornet (flumetsulam + clopyralid), Prowl (pendimethalin), dicamba, or 2,4-D.
Do not mix or load within 50 feet of wells, sink holes, streams, rivers, lakes, or reservoirs. Do not apply within 66 feet of areas where field surface runoff drains into streams or rivers. Do not apply within 200 feet of natural or impounded lakes or reservoirs.
PPS or PRE. Conventional or Roundup Ready corn. Apply up to 30 days prior to corn planting or prior to corn emergence.
EPOST. Apply in corn from emergence up to 12 inches tall. For glyphosate resistant corn only.
EPOST. For glyphosate-tolerant corn only. Rate is 3.6-4 pt/A. Add NIS at 1-2 qt/100 gal water and AMS at 8.5-17 lb/100 gal water.
Using UAN rather than AMS could result in crop injury. Minimum carrier is 10 gpa for ground applications. An application of 3.6 pt/A will be equivalent to 3 oz/A Callisto, 0.99 pt/A Dual Magnum, and 24 oz/A Touchdown HiTech.
Early preplant rates are 2.1-2.6 qt for Bicep II Magnum and 1.5-2.2 qt for Bicep Lite II Magnum per acre. Maximum atrazine rate is
1.6 lb ai per acre on highly erodible land with less than 30% residue.
Tank-mixes and premixes for most situations are listed below. Labeling also includes preemergence mixes with Balance or postemergence mixes with Banvel or burndown with Gramoxone, Roundup, 2-4-D, Banvel, or Marksman. Refer to label restrictions or the section for each herbicide. Mix 1-2 pt Dual II Magnum + 1-2 lb ai atrazine per acre. Very good to excellent control of several annual grasses and small-seeded annual broadleaves. Consistent performance.
EPOST. May be applied before the 2-leaf stage of weeds, but before corn is 5 inches. Less consistent. Primarily an alternative if unforeseen conditions prevent earlier application. Harrowing or rotary hoeing to remove emerged weeds improves results.
Tank-mix for special label for reduced rates of Dual and postemergence herbicides is listed below.
POST. Mix 0.67-1.33 pt Dual II Magnum or Cinch with 0.33-0.45 oz Accent plus 5 oz NorthStar per acre. Add NIS at 1 qt/100 gal plus 2-4 qt 28% N per acre. Do not use COC.
ACETOCHLOR PRODUCTS Site of Action: 15 ($12.10-51.65)
HARNESS, SURPASS, VOLLEY, BREAKFREE, CADENCE, TOPNOTCH or DEGREE(acetochlor) 1.5-3.75 pt Surpass, Volley, Overtime, Breakfree, or Cadence 6.4L (1.2-3 lb ai), 2-3.75 qt TopNotch 3.2L 1.25-3 pt Harness 7L or 6-12 lb Harness 20G (1.2-2.4 lb ai), 2.75-5.5 pt Degree 3.8L Products contain acetochlor plus safener. TopNotch is a microencapsulated formulation (Surpass) targeted to no-till. Degree is an encapsulated formulation (Harness) that is released by temperature. The acetochlor and safener in Degree release as temperature rises above 50o F extending control further into the weed emergence period. Annual grass control has been very good to excellent.
It has been more consistent than some preemergence treatments when rainfall was limited. Control of small-seeded annual broadleaves such as pigweed is more variable but is fair to good in many tests. Gives fair to good control of waterhemp.
General labeling and precautions are similar. Crop tolerance is very good. Approved rotational crops include wheat (4 months);
soybeans and milo the following year.
Several environmental restrictions are intended to reduce the risk of groundwater contamination. Mixing and loading pads are required if within 50 feet of a well. Application is prohibited on sandy soil with less than 3% O.M. if groundwater is within 30 feet of the surface. In addition, loamy sands with less than 2% O.M. or sandy loams with less than 1% O.M. should not be treated if groundwater is within 30 feet. Minimum carrier is 10 gpa. Acetochlor is not approved for air application.
EPPS. For no-till or reduced tillage systems. Apply Harness, Surpass, Breakfree, or Volley within 30 days of planting or TopNotch within 40 days. High rates are suggested if applied more than 10 days before planting. Incorporated applications should be made within 10 days of planting. Harness may be used as a split application if applied within 45 days of planting. Slightly higher rates are used for early preplant applications. Performance is best in early, dry spring seasons.
SPPI. Apply within 14 days of planting. Incorporate shallowly into the top 1-2 inches.
PRE. Apply within 5 days of the last tillage. Rainfall required.