diquat (Reglone)
see Preharvest Desiccation at end of this section
ethalfluralin (Curbit)
Dill grown for oil
Rate 0.56 to 1.1 lb ai/A (1.5 to 3 pints/A Curbit)
Time Apply after seeding but prior to emergence of crop and weeds.
Remarks SLN OR-120002. Adequate rain or irrigation after application before weed seedlings emerge, provides the most effective weed control.
Caution Refer to main labels for crop rotation restrictions. Preharvest interval is 91 days.
Site of action Group 3: microtubule assembly inhibitor
Chemical family Dinitroaniline
fluazifop (Fusilade DX)
Carrot seed only
Rate 0.063 to 0.25 lb ai/A (4 to 16 oz/A Fusilade DX)
Time Apply to actively growing grasses.
Remarks Identify grasses and adjust rates for susceptibility and weed growth stage as on label. Results often are erratic on grasses stressed by lack of vigor, drought, heat, or low fertility. More mature grasses and quackgrass can be controlled but may require two applications. Annual bluegrass and all fine fescues resist treatment. Do not exceed 48 oz/A per season.
Caution Do not apply if rain is expected within 1 hr. Do not rotate to grass crops such as corn and cereals within 60 days of last application. Grazing any plant products or residue is prohibited.
Site of action Group 1: acetyl CoA carboxylase (ACCase) inhibitor
Chemical family Aryloxyphenoxy propionate
oxyfluorfen (Galigan 2E)
Oregon-carrot seed only
Rate 0.25 to 0.5 lb ai/A (1 to 2 pints/A Galigan 2E)
Time Dormant application: Directed spray applications using drop nozzles between the crop rows can be made in the dormant season from November 15 to February 28.
Spring Application: Begin applications in early spring. Make application as a broadcast spray when carrots are at least 8-10 inches tall. For best results, apply when weeds are in the 2 to 4 leaf stage.
Layby Application: Make application at layby with a directed spray using drop nozzles between the rows and in the furrows. For best results, apply when weeds are in the 2 to 4 leaf stage. Do not make a broadcast application over the top of the carrots at this timing.
Remarks SLN label OR-190007. Do not exceed 0.5 lb ai/A per crop cycle. Add 2 to 4 pints of an 80% active nonionic surfactant if postemergence weed control is desired. Maintain a 25-ft vegetative buffer between treated areas and water. Reduce crop injury potential by using lower rate, by not applying soon after or in combination with linuron, and by applying to large carrots. Grazing crop residue or treated fields prohibited.
Site of action Group 14: protoporphyrinogen oxidase inhibitor
Chemical family Diphenylether
pendimethalin (Prowl H2O, Stealth, Satellite Hydrocap, Pin-Dee 3.3, Aquapen 3.8)
Carrot seed only
Rate 0.45 to 1.9 lb ai/A (1 to 4 pints/A Prowl H2O)
Time Apply at last cultivation (layby) as a directed spray.
Remarks Adequate rain or irrigation after application, before weed seedlings emerge, provides the most effective weed control. Inhibits mitosis in roots and shoots.
Caution Do not spray broadcast over the top of carrots, because crop may be injured. Use protective shields on sprayer to avoid spray contact with foliage. Refer to main labels for crop rotation restrictions. Preharvest interval is 60 days. Do not use any plant residue or product for food or feed. Rotate to tolerant crops other than winter wheat or barley if rates exceed 1.5 lb/A.
Site of action Group 3: microtubule assembly inhibitor
Chemical family Dinitroaniline
prometryn (Caparol 4L)
Washington-carrot, parsley, parsnip, and dill seed
Oregon-carrot, coriander, and parsley seed
Rate 0.5 to 1 lb ai/A (1 to 2 pints/A product)
Time Apply postemergence when crop has three to five true leaves, when weeds are not more than 2 inches tall, or as a layby treatment, preferably as a directed spray.
Remarks SLN labels WA-960014 and OR-04002. This indemnified label is available only through the Syngenta Indemnified Label website (farmassist.com). Follow the steps listed in "Beet seed" section of this chapter to acquire the indemnified label. Use in at least 30 gal/A spray volume. Use adjuvants only with layby applications.
Caution Do not use any part of the crop for food or feed. Do not exceed 4 pints/A per crop. To reduce the chance of injuring rotational crops, disk the field deeply and irrigate at least twice soon after harvest. Using prometryn on soils with excess salts or that are highly calcareous may injure crop.
Site of action Group 5: photosystem II inhibitor
Chemical family Triazine
quizalofop (Assure II, Targa)
Carrot seed only
Rate 0.069 to 0.17 lb ai/A (5 to 12 oz/A Assure II)
Time Apply at optimum growth stage listed on label.
Remarks Identify susceptible grasses and add 4 quarts crop oil concentrate or 1 quart nonionic surfactant/100 gal spray mix. Grass control may be reduced if applied immediately before or after applying a broadleaf herbicide.
Caution Do not apply within 14 days of anticipated bloom. Do not mix with, or apply with, any other pesticide except as specified on label. Do not apply to plants stressed from lack of moisture, cold, or injury from herbicides, insects, or disease. Do not use any treated portion of crop for food or feed. Do not exceed 25 oz/A per season. Do not make more than 2 applications per acre per season, or make a second application within 7 days of the first. Grower is responsible to notify processing facility of quizalafop use, so that seed can be marked "Not for human or animal consumption".
Site of action Group 1: acetyl CoA carboxylase (ACCase) inhibitor
Chemical family Aryloxyphenoxypropionate
sethoxydim (Poast)
Rate 0.28 to 0.47 lb ai/A (1.5 to 2.5 pints/A Poast)
Time Apply for barnyardgrass and other grass control at 3- to 12-inch stage of growth. Add 2 pints/A nonphytotoxic crop oil concentrate to improve leaf absorption.
Remarks Control often is erratic on grasses stunted or stressed by drought, heat, or low fertility. Resistant grasses include annual bluegrass and all fine fescues, but quackgrass can be suppressed.
Site of action Group 1: acetyl CoA carboxylase (ACCase) inhibitor
Chemical family Cyclohexanedione