Carrot Seed (and other Apiaceae or Umbelliferae seed crops)

bensulide (Prefar 4-E)

Parsley and cilantro seed

Rate 5 to 6 lb ai/a (5 to 6 quarts/a Prefar 4-E)

Time Apply preplant or preemergence.

Remarks Use lower rates on light, coarse soils and on soils with low organic matter. Application to cold, wet soils, due to rains or poor drainage, during germination period may reduce crop stands or yields. Do not exceed 6 lb ai/a per season.

Site of action Group 8: lipid synthesis inhibitor but not an ACCase inhibitor

Chemical family Thiocarbamate

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 labels OR-120002 and WA-170003. 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 hour. 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

linuron (Lorox 50 DF)

Carrot and parsnip seed

Rate 0.75 to 1.5 lb ai/a (1.5 to 3 lb/a 50DF product)

Time Apply preemergence (Oregon and Washington only) or postemergence when carrots are at least 3 inches tall, when grass weeds are not more than 2 inches tall, and when broadleaf weeds are not more than 6 inches tall.

Caution Plant seed at least 0.5 inches deep. Do not exceed 40 psi spray pressure. Weed control may be poor if daytime highs are below 50°F. Crop may be injured if linuron is mixed with surfactants, nitrogen, or fertilizer solutions, or applied at temperatures above 85°F. Applications may be repeated, but do not exceed 1.5 lb ai/a per season. Do not apply on sandy, loamy sands, gravelly soils, or soils with less than 1% organic matter. See label for planting rotation crops within 12 months.

Site of action Group 7: photosystem II inhibitor

Chemical family Substituted urea

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)

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. 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)

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.

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

S-metolachlor (Dual Magnum)

Idaho and Oregon only-carrot and parsnip seed

Rate Consult label.

Time Broadcast preplant with ground application equipment.

Remarks Uniformly mix into top 2 inches of soil. SLN labels ID-150006 and OR-060012. This indemnified label is available only through the Syngenta Indemnified Labels website (https://www.syngenta-us.com/labels/indemnified-label-search)). Follow the steps listed in "Beet seed" section of this chapter to acquire the indemnified label.

Caution Restricted-use herbicide in Washington to protect surface and groundwater. Crop may be injured if environmental conditions are unfavorable. Do not feed or graze forage or fodder, or cut for hay or forage. No part of the treated field, including seed, seed screenings, hay, forage, or stubble, may be used for human or animal consumption. See label for all other precautions and regulations.

Site of action Group 15: inhibits very long chain fatty acid synthesis

Chemical family Chloroacetamide

trifluralin (Treflan HFP)

Carrot seed only

Rate 0.5 to 1 lb ai/a (1 to 2 pints/a product)

Time Apply from 3 weeks to immediately before planting; incorporate 2 to 3 inches deep within 24 hr by cross-disking or using a power take-off rotary tiller.

Remarks Spray only once; avoid overlaps. Consult label for restrictions on planting sensitive crops within 12 months.

Site of action Group 3: microtubule assembly inhibitor

Chemical family Dinitroaniline