Winter Wheat―West of Cascades
 Andrew Hulting
Revised December 1, 2008
WINTER WHEAT―West of Cascades―Wild Oat, Italian Ryegrass, and Other Grass Weeds 
•  triallate (Far-Go)
Rate  1.25 lb ai/A (1.25 quarts/A Far-Go)
Time  Apply just before or soon after seeding. Incorporate immediately 2 to 3 inches deep, but above the planted winter wheat seeds, with two harrowings at right angles.
Remarks  In a roughly tilled field or one with heavy crop residue, weed control may be reduced due to poor incorporation of the herbicide. Additional herbicide treatments may be necessary for dense infestations of Italian ryegrass or wild oat.
Site of action  Group 8: lipid synthesis inhibitor but not an ACCase inhibitor
Chemical family  Thiocarbamate
•  diuron (several trade names)
Rate  1.2 to 1.6 lb ai/A
Time  Apply as soon as possible after planting. If wheat and weeds have emerged, apply before weeds are 3 to 4 inches tall.
Remarks  Rain is required to activate chemical. Results are best if rain begins within 2 wk of application. Winter wheat must be seeded more than 1.5 inches deep. Italian ryegrass has developed resistance to diuron in some fields in western Oregon. Diuron will control rattail fescue, susceptible annual bluegrass, and many broadleaf weeds but will not control wild oats.
Caution  Crop may be injured if severe winter stress, disease, or insect damage follows application. Do not use on sand or loamy sand soils, on gravelly or sandy loams low in organic matter, or on thinly covered or exposed subsoil areas (clay knobs). Do not treat winter wheat planted less than 1 inch deep. 
Site of action  Group 7: photosystem II inhibitor
Chemical family  Substituted urea
•  trifluralin (several trade names)
Rate  0.5 to 1.0 lb ai/A 
Time  Trifluralin can be applied as a preplant incorporated treatment up to 3 wk before planting winter wheat or as a postplant incorporated treatment immediately following winter wheat planting.
Remarks  For grass and broadleaf control. Trifluralin will not control established weed seedlings. Incorporate trifluralin with two harrowings at right angles following applications. Rate depends on soil type and the application timing used.
Caution  Selectivity of trifluralin depends on the placement relative to planted winter wheat seed. Crop may be severely injured if winter wheat seed is planted into herbicide-treated soil. Do not replant treated areas to annual or perennial grass seed crops within 1 yr of application; see individual labels for more specific instructions on limiting injury to rotational crops.
Site of action  Group 3: Microtubule assembly inhibitor
Chemical family  Dinitroaniline
•  triallate (Far-Go) +
•  diuron (several trade names)
Rate  1.25 lb ai/A triallate (1.25 quarts/A Far-Go) + 1.2 to 1.6 lb ai/A diuron
Time  Apply triallate just before or soon after seeding. Incorporate immediately 2 to 3 inches deep, but above the planted winter wheat seeds, with two harrowings at right angles. Apply diuron pre- or postemergence after rain settles soil.
Remarks  Triallate is safer on winter wheat if applied after planting. Triallate is not effective against broadleaf weeds but is effective on wild oat and Italian ryegrass.
Site of action  (triallate) Group 8: lipid synthesis inhibitor but not an ACCase inhibitor; (diuron) Group 7: photosystem II inhibitor
Chemical family  (triallate) thiocarbamate; (diuron) substituted urea
•  diuron (several trade names) +
•  chlorsulfuron + metsulfuron (several trade names) 
Rate  0.8 to 1.2 lb ai/A diuron + 0.014 to 0.019 lb ai/A chlorsulfuron + metsulfuron
Time  Apply pre- or postemergence any time after winter wheat is in two-leaf stage but before boot.
Remarks  For best results, apply preemergence to Italian ryegrass. Do not use surfactant. This treatment is often not effective on wild oat
Caution  See individual labels for crop rotation restrictions. Many crops may not be planted within 2 yr or longer after application. Perennial and annual ryegrass and crimson clover may not be planted for 9 mo; barley, and oats for 10 mo; and red clover for 15 mo after a Finesse application. There are no restrictions on rotations to wheat, rye, or triticale.
Site of action  (diuron) Group 7: photosystem II inhibitor; (chlorsulfuron and metsulfuron) Group 2: acetolactate synthase (ALS) inhibitor
Chemical family  (diuron) substituted urea; (chlorsulfuron and metsulfuron) sulfonylurea
•  trifluralin (several trade names) +
•  diuron (several trade names)
Rate  0.75 lb ai/A trifluralin  + 1.2 to 1.6 lb ai/A diuron
Time  Apply trifluralin after planting but before wheat germinates. Immediately incorporate trifluralin above the planted winter wheat seeds with two harrowings at right angles. Apply diuron pre- or postemergence after rain settles soil.
Remarks  Use lower diuron rate if Italian ryegrass escapes are fewer than five plants/sq ft Higher rate may injure crop, but this may be offset by better weed control when the weed population is high. This treatment gives fair control of annual bromes but poor control of wild oat.
Caution  Selectivity of trifluralin and diuron depends on their placement relative to winter wheat seed. Crop may be severely injured if winter wheat seed is in herbicide treated soil. Do not replant treated areas to any other crop within 1 yr of application.
Site of action  (trifluralin) Group 3: microtubule assembly inhibitor; (diuron) Group 7: photosystem II inhibitor
Chemical family  (trifluralin) dinitroaniline; (diuron) substituted urea
•  metribuzin (several trade names)
Rate  0.094 to 0.5 lb ai/A
Time  Apply 0.094 to 0.187 lb ai/A in fall after winter wheat has at least two leaves. Apply 0.314 to 0.5 lb ai/A in spring when winter wheat has more than four tillers and secondary roots are more than 1 inch long.
Remarks  Most effective if applied before weedy grasses exceed the two-leaf stage; therefore, lower rates in fall usually are more effective than higher rates in spring. If applying metribuzin sequentially, allow at least 45 days between applications. Adding a nonionic surfactant with the fall application usually improves control. To control severe grass infestations see entry for triallate + metribuzin + Finesse below. Metribuzin applied at 0.28 lb ai/A controls speedwell species.
Caution  Some winter wheat varieties are sensitive to metribuzin. Do not apply on ‘Yamhill’ wheat. ‘Hill 81’ is less tolerant than ‘Stephens’. See label for maximum application rate on different soil types. Do not exceed 0.5 lb ai/A/yr.
Site of action  Group 5: photosystem II inhibitor
Chemical family  Triazine
•  triallate (Far-Go) +
•  metribuzin (several trade names)
Rate  1.25 lb/A triallate (1.25 quarts/A Far-Go) + 0.094 to 0.5 lb ai/A metribuzin 
Time  Triallate is safer on wheat if applied after planting. Apply triallate just before or soon after seeding and incorporate immediately 2 to 3 inches deep, but above wheat seed, with two harrowings at right angles. See above for rates and timings of metribuzin.
Remarks  Triallate is ineffective against broadleaf weeds. Treatment will provide fair to good control of Italian ryegrass, wild oat, and annual bromes. Metribuzin will also control many broadleaf weeds.
Site of action  (triallate) Group 8: lipid synthesis inhibitor but not an ACCase inhibitor; (metribuzin) Group 5: photosystem II inhibitor
Chemical family  (triallate) thiocarbamate; (metribuzin) triazine
•  triallate (Far-Go) +
•  metribuzin (several trade names) +
•  chlorsulfuron + metsulfuron (several trade names) 
Rate  1.25 lb/A triallate (1.25 quarts/A Far-Go) + 0.141 lb ai/A metribuzin + 0.018 lb ai/A chlorsulfuron + metsulfuron 
Time  Apply triallate just before or soon after seeding and incorporate immediately 2 to 3 inches deep, but above planted winter wheat seed, with two harrowings at right angles. Apply metribuzin + chlorsulfuron + metsulfuron when winter wheat is in the two-leaf stage. This application is most effective before grass weeds exceed the two-leaf stage.
Remarks  Recommended for fields heavily infested with annual bromes and/or Italian ryegrass with suspected diclofop or diuron resistance. Adding an 80% ai nonionic surfactant improves control. Also gives fair to good control of wild oat.
Caution  Observe the same use precautions given above for metribuzin and  chlorsulfuron + metsulfuron alone.
Site of action (triallate) Group 8: lipid synthesis inhibitor but not an ACCase inhibitor; (metribuzin) Group 5: photosystem II inhibitor; (chlorsulfuron and metsulfuron) Group 2: acetolactate synthase (ALS) inhibitor
Chemical family (triallate) thiocarbamate; (metribuzin) triazine; (chlorsulfuron and metsulfuron) sulfonylurea
•  linuron (Linex)
Rate  Make a single application of Linex 4L at 2 to 3.5 pints/A
Time  Apply as soon as possible after planting winter wheat. If winter wheat and weeds have emerged, apply before weeds are 3 inches tall. Note that application to actively growing plants may result in temporary crop chlorosis. Do not apply to winter wheat in the boot stage of maturity or when daily temperatures exceed 60°F, or crop may be injured.
Remarks  When using Linex, plant winter wheat seed at least 1 inch deep. When planting in very dry conditions, use Linex only after rain or irrigation settles the soil.
Caution  Crop may be injured if severe winter stress, disease, or insect damage follows application or from failure to observe correct winter wheat planting depth. Do not use Linex with other pesticides (except those listed in label), surfactants, or nitrogen solutions after winter wheat emerges. See label for crop rotation restrictions; any crop registered for the rate of Linex that was applied may be replanted immediately. Do not plant any other crop until 12 months after the last Linex application.
Site of action  Group 7: photosystem II inhibitor
Chemical family  Substituted urea 
•  pendimethalin (Prowl H20)
Rate  0.71 to 1.42 lb ai/A (1.5 to 3 pints/A Prowl H20)
Time  Apply postemergence when winter wheat is at least 1 leaf through flag leaf emergence, but prior to weed emergence. Prowl H2O will not control emerged weeds but may be useful to suppress additional weed flushes or late emerging weed species.
Remarks  To control and suppress annual grasses and broadleaf weeds in winter wheat. May be tank mixed with other postemergence herbicides labeled in wheat to control established weeds and to broaden the weed control spectrum. Refer to label for approved tank mix options.
Caution  Application rate is dependent on soil type. Use lower rates on coarse-textured soils and higher rates on medium- to fine-texture soils.
Site of action  Group 3: microtubule assembly inhibitor
Chemical family  Dinitroaniline
•  flufenacet (Define SC or Define DF) 
Oregon only
Rate  0.27 to 0.34 lb ai/A (4.3 to 10.75 fl oz/A Define SC or 3.6 to 9 oz/A Define DF)
Time  Apply early postemergence when winter wheat is between spike and three-leaf growth stage.
Remarks  To control and suppress annual grasses and broadleaf weeds in winter wheat. Flufenacet may be tank-mixed with metribuzin,  but do not exceed a total of the labeled metribuzin rate listed on the specific metribuzin  label for soil type and winter wheat stage at application. For sequential applications of Define and metribuzin, do not exceed a total of 0.5 lb ai/A of metribuzin per year. See label for suggested timing of sequential applications of Define and metribuzin based on environmental conditions. Special local needs labels OR-070030 and OR-070031.
Caution  Use lower Define rates on coarse soils. Do not use on soils with less than 1% organic matter or a pH greater than 7.5. For best control of weeds emerging with winter wheat crop, plant winter wheat after initial flush of weeds has been controlled with tillage or a burndown herbicide. Do not graze treated winter wheat for at least 30 days after applying. Do not apply more than once per year. Do not tank-mix Define with diuron or apply in tank-mixtures with adjuvants. Not all available newer winter wheat releases and varieties have been tested for tolerance to Define.
Site of action  Group 15: inhibits very long chain fatty acid synthesis
Chemical family  Oxyacetamide
breakhere  •  flufenacet + metribuzin (Axiom DF)
Rate  0.13 to 0.31 lb ai/A flufenacet + 0.034 to 0.087 lb ai/A metribuzin (4 to 10 oz/A Axiom)
Time  Apply early postemergence when winter wheat is between spike and three-leaf growth stage.
Remarks  For control and suppression of annual grasses and broadleaf weeds in winter wheat. Axiom may be tank-mixed metribuzin, but do not exceed a total of more than the labeled metribuzin rate specified on the specific metribuzin label for soil type and winter wheat stage at application. For sequential applications of Axiom and metribuzin do not exceed a total of 0.5 lb ai/A/yr of metribuzin. See label for suggested timing of sequential applications of Axiom and metribuzin based on environmental conditions.
Caution  Use lower Axiom rates on coarse soils and soils with low organic matter and high pH. For best control of weeds emerging with winter wheat crop, plant winter wheat after initial flushes of weeds have been controlled with tillage or a burndown herbicide. Do not graze treated winter wheat for at least 30 days after applying. Do not exceed one application or 10 oz/A of Axiom per year. Do not apply in tank-mixtures with adjuvants. Certain winter wheat varieties are sensitive to Axiom, including 'Yamhill'. See label for listed varieties sensitive to Axiom. Not all available newer winter wheat releases and varieties have been tested for tolerance to Axiom.
Site of action  (flufenacet) Group 15: inhibits very long chain fatty acid synthesis; (metribuzin) Group 5: photosystem II inhibitor
Chemical family  (flufenacet) oxyacetamide; (metribuzin) triazine
•  imazamethabenz (Assert)
Rate  0.41 to 0.47 lb ai/A (1.3 to 1.5 pints/A Assert)
Time  Apply from the one- to four-leaf stage of wild oat. Apply to wheat from the two-leaf stage up to jointing.
Remarks  For control of wild oat. and roughstalk bluegrass. and certain broadleaf weeds in winter wheat. Use 80% ai nonionic surfactant at 2 pints/100 gal. If wild oat exceeds 25 plants/sq ft, use a minimum spray volume of 15 gal/A by ground. Allow at least 2 days of above-freezing temperatures before and after applying, or weed control may be reduced. Assert will not control Italian ryegrass.
Caution  See label for tank-mixing instructions and crop rotation restrictions. Do not tank-mix with phosphorous fertilizers. Do not tank-mix with dicamba, MCPA amine, or 2,4-D amine. Do not plant crops other than wheat, barley, corn, soybean, safflower, edible beans, or sunflowers for 15 mo or sugar beets for 20 mo after application. Do not graze treated wheat or cut treated wheat for forage.
Site of action  Group 2: acetolactate synthase (ALS) inhibitor 
Chemical family  Imidazolinone
•  flucarbazone (Pre-Pare and Everest)
Rate  0.009 lb ai/A (0.3 oz/A Pre-Pare) and/or 0.009 to 0.018 lb ai/A (0.3-0.6 oz/A Everest)
Time  Apply Everest postemergence to actively growing wild oats and Italian ryegrass that have one leaf to two tillers and when winter wheat is between one leaf and the beginning of jointing.
Remarks  Pre-Pare may be tank mixed with glyphosate to improve burndown control of many grass and broadleaf weed species and to provide soil residual weed control prior to planting winter wheat. Use with nonionic surfactant (0.25%) in 5 to 10 gal/A spray volume. Including a liquid nitrogen or ammonium sulfate fertilizer is also recommended on the labels. See Pre‑Pare and Everest labels for further directions.
Caution  Do not apply Everest after jointing starts. Do not apply Everest more than once per season, and follow tank-mixing instructions carefully. Weed control may be reduced and winter wheat injury increased when applied during temperature extremes or when soil is saturated. Do not exceed a total of 0.026 lb ai/A of the two products combined per growing season. Consult both labels for crop rotation restrictions
Site of action  Group 2: acetolactate synthase (ALS) inhibitor 
Chemical family  Sulfonylaminocarbonyltriazolinone
•  propoxycarbazone-sodium (Olympus)
Rate  0.027 to 0.04 lb ai/A (0.6 to 0.9 oz/A Olympus)
Time  Fall or spring―apply specified dosage per acre as a postemergence broadcast spray to actively growing wild oat and annual brome grasses in the two-leaf to two-tiller stage. Fall and spring―apply 0.6 to 0.9 oz/A Olympus in fall and then 0.3 to 0.6 oz/A Olympus in spring as a postemergence broadcast spray. Apply from crop emergence to before jointing begins.
Remarks  Use with nonionic surfactant (0.25% to 0.5% v/v). Do not exceed 1.2 oz/A Olympus per crop year. Fall applications may not control spring-germinating weeds. Olympus will not control Italian ryegrass.
Caution  See label for broadleaf tank-mix options with Olympus and additional cautions.
Site of action  Group 2: acetolactate synthase (ALS) inhibitor
Chemical family  Sulfonylaminocarbonyltriazolinone
•  propoxycarbazone-sodium + mesosulfuron-methyl (Olympus Flex)
Rate  0.021 to 0.025 lb ai/A (3 to 3.5 oz/A Olympus Flex) plus adjuvant system
Time  Apply to winter wheat from emergence to before jointing begins. Fall or spring: apply specified dosage as a postemergence broadcast spray to actively growing wild oat and annual brome grasses in the one-leaf to two-tiller stage. A nonionic surfactant (0.5% v/v) with ammonium nitrogen (1 to 2 quarts/A) or ammonium sulfate (1.5 to 3 lb/A) fertilizer must be tank-mixed with Olympus Flex. Time application by crop stage, not weed stage. 
Remarks  Do not apply more than 3.5 oz/A Olympus Flex per crop year.
Caution  Do not use with organosilicone-based surfactants.
Site of action  (both) Group 2: acetolactate synthase (ALS) inhibitor
Chemical family  (propoxycarbazone-sodium) sulfonylaminocarbonyltriazolinone; (mesosulfuron-methyl) sulfonylurea
•  mesosulfuron-methyl (Osprey)
Rate  0.009 to 0.0134 lb ai/A (3.2 to 4.75 oz/A Osprey)
Time  Fall or spring: Apply specified dosage per acre as a postemergence broadcast spray to young, actively growing weeds (one-leaf to two-tiller growth stage). Apply from crop emergence to the winter wheat jointing stage.
Remarks  For Italian ryegrass, use 4.75 oz/A Osprey. Use the 3.2 oz/A Osprey rate for wild oat control if wild oat is the only target weed. A nonionic surfactant (0.5% v/v) with ammonium nitrogen (1 to 2 quarts/A) or ammonium sulfate (1.5 to 3 lb/A) fertilizer must be tank-mixed with Osprey. Do not exceed one application or 4.75 oz/A Osprey per winter wheat season.
Caution  Crop may be injured if frost occurs shortly after application to actively growing wheat. Consult label for broadleaf tank-mix options with Osprey and additional cautions.
Site of action  Group 2: acetolactate synthase (ALS) inhibitor
Chemical family  Sulfonylurea 
•  pyroxsulam (PowerFlex)
Rate  0.016 lb ai/A (3.5 oz/A PowerFlex)
Time  Apply in either fall or spring to actively growing winter wheat from the three-leaf to jointing stage and after most weeds have emerged. PowerFlex will control or suppress Italian ryegrass, downy brome, cheat, and has good broadleaf activity.
 Remarks  A nonionic surfactant (0.25-0.5% v/v) with ammonium sulfate (1.5 lb/A) fertilizer must be tank-mixed with PowerFlex for maximum efficacy. Do not exceed one application of PowerFlex per winter wheat season or make split applications. When applying with fluid fertilizer as a carrier, spray solution should not be composed of more than 50% liquid nitrogen and should not exceed 30 lb of actual nitrogen per acre.
Caution  For winter wheat only. Do not tank-mix with products containing dicamba or amine formulations of 2,4-D or MCP or organophosphate insecticides. Crop rotation restriction is 9 mo for field and sweet corn, grasses, alfalfa and canola.
Site of action  Group 2: acetolactate synthase (ALS) inhibitor
Chemical family  Triazolopyrimidine sulfonamide 
•  sulfosulfuron (Maverick)
Rate  0.031 lb ai/A sulfosulfuron (0.67 oz/A Maverick)
Time  Apply only once, at the maximum rate of 0.67 oz/A per season. Apply after wheat emerges but before jointing. Apply to weeds postemergence, when soil moisture is adequate for active growth. For best control of brome species, apply at the two- to three-leaf growth stage.
Remarks  Maverick’s strong point is downy brome control, found mostly east of the Cascades, but it also is good on quackgrass and cheatgrass and fair on Italian ryegrass and wild oat. Bedstraw is among the broadleaf weeds controlled. Use with an 80% ai nonionic surfactant at 2 quarts/100 gal.
Caution  Do not plant any crop except spring or winter wheat for 1 yr after applying Maverick. 
Site of action  Group 2: acetolactate synthase (ALS) inhibitor
Chemical family  Sulfonylurea
•  fenoxaprop (Puma) 
Rate  0.08 lb ai/A (0.66 pint/A Puma)
Time  Apply to winter wheat from emergence to 70 days before harvest. Apply to wild oat from the two-leaf to two-tiller stage of growth and to blackgrass from the two-leaf through advanced tillering stages.
Remarks  Blackgrass is very sensitive to fenoxaprop, but thorough coverage is needed to control well-tillered plants. Fenoxaprop will not control Italian ryegrass. See label for tank-mix options with broadleaf herbicides. Wild oat populations have developed resistance to fenoxaprop in some fields in Oregon. Puma has the same mode of action as Hoelon, Achieve, Discover, Axial XL, Poast, Assure II, and Fusilade, so weed populations resistant to these herbicides may be cross resistant to Puma and vice versa.
Caution  Cool, wet conditions at application may temporarily yellow and/or stunt the winter wheat.
Site of action  Group 1: acetyl CoA carboxylase (ACCase) inhibitor
Chemical family  Aryloxyphenoxy propionate
•  diclofop (Hoelon)
Rate  0.75 to 1 lb ai/A (2 to 2.67 pints/A Hoelon)
Time  Apply after wild oat is in two- to three-leaf growth stage. Apply before Italian ryegrass reaches two- to three-tiller growth stage. Results are best if applied before February. Apply before jointing stage of winter wheat growth.
Remarks  Do not apply more than once per growing season. See label for approved tank-mixes. Do not apply other broadleaf herbicides within 5 days of diclofop application. Wild oat and Italian ryegrass populations have developed resistance to diclofop in some fields in western Oregon.
Caution  Hoelon is a restricted-use herbicide.
Site of action  Group 1: acetyl CoA carboxylase (ACCase) inhibitor
Chemical family  Aryloxyphenoxy propionate
•  tralkoxydim (Achieve Liquid)
Rate  0.18 to 0.24 lb ai/A (6.9 to 9.2 fl oz/A Achieve Liquid). Use high rate if soil is dry, weeds are large, weed population is high, or crop canopy is dense. Do not exceed 0.24 lb ai/A per season.
Time  Apply to winter wheat between the two-leaf stage and boot stage. For best control, apply in fall when wild oats or Italian ryegrass has one to four leaves.
Remarks  Wild oat may be controlled up to the emergence of the third tiller. Weeds emerging after application will not be controlled.
Caution  Do not plant cereal grains and leafy vegetables for 30 days after applying Achieve. Wait 106 days before rotating to any other crop.
Site of action  Group 1: acetyl CoA carboxylase (ACCase) inhibitor
Chemical family  Cyclohexanedione
•  clodinafop-propargyl ( Discover NG)
Rate  0.05 to 0.063 lb ai/A (12.8 to 16 oz/A Discover NG). Methylated seed oil may be added with Discover NG at 2 pints/100 gal of spray volume mixture.
Time  Apply to winter wheat from the two-leaf to preboot stage. Do not apply to winter wheat in the fall. Apply to wild oat with one to six leaves on the main stem and to Italian ryegrass with one to five leaves on the main stem.
Remarks  Winter wheat is more susceptible to injury when temperatures 48 hours before or after application are below 40°F. See label for crop rotation restrictions.
Caution  Apply only once per season. Do not graze or feed forage from treated areas for at least 30 days after application. Preharvest interval is 60 days. Do not apply to a crop stressed by conditions such as drought, frost, low fertility, or pest damage; crop may be injured.
Site of action  Group 1: acetyl CoA carboxylase (ACCase) inhibitor
Chemical family  Aryloxyphenoxy propionate
•  pinoxaden (Axial and Axial XL)
Rate  0.054 lb ai/A (8.2 oz/A Axial + 9.6 oz/A Adigor adjuvant or 16.4 oz/A Axial XL)
Time  Apply to winter wheat from the two-leaf to preboot stage. Apply to wild oat with one to six leaves on the main stem and to Italian ryegrass with one to five leaves on the main stem.
Remarks  See label for crop rotation restrictions and labeled broadleaf weed control tank-mix partners.
Caution  Apply only once per season. Do not apply to a crop stressed by conditions such as drought, frost, low fertility, or pest damage; crop may be injured.  
Site of action  Group 1: acetyl CoA carboxylase (ACCase) inhibitor
Chemical family  Phenylpyrazolin

breakhere  
WINTER WHEAT―West of Cascades―Broadleaf Weeds
•  bromoxynil (several trade names)
Rate  0.375 to 0.5 lb ai/A 
Time  Apply from winter wheat emergence to the boot stage. Apply to weeds up to the four-leaf stage or 2 inches high or 1 inch wide, whichever is first. Certain weeds may be controlled when larger; see label for size recommendations and application timings.
Remarks  Do not apply to crops under moisture stress. Do not exceed 0.5 lb ai/A total per season.
Site of action  Group 6: photosystem II inhibitor
Chemical family  Nitrile
•  bromoxynil + MCPA (Bronate)
Rate  0.25 to 0.5 lb ai/A bromoxynil + 0.25 to 0.5 lb ae/A MCPA (1 to 2 pints/A Bronate)
Time  Apply to winter wheat after three-leaf stage but before boot stage. Apply to weeds up to the four-leaf stage or 2 inches high. Certain larger weeds may be controlled; see label for size recommendations and application timings.
Remarks  Do not apply when crops are under moisture stress.
Site of action  (bromoxynil) Group 6: photosystem II inhibitor; (MCPA) Group 4: synthetic auxin
Chemical family  (bromoxynil) nitrile; (MCPA) phenoxy acetic acid
•  bromoxynil + pyrasulfotole (Huskie) 
Rate  0.186 to 0.254 lb ai/A (11 to 15 oz/A Huskie)
Time  Apply to winter wheat from one leaf up to flag-leaf emergence. See label for weed size recommendations and application timings, but control of most species is best at the11 fl oz/A rate when weeds have from one to six leaves. 
Remarks  For most consistent weed control under adverse growing conditions, add AMS or an ammonium nitrogen source as directed by the spray additives section of the label. Huskie may be tank-mixed with a variety of other broadleaf and grass herbicides; see label for instructions.
Caution  See label for crop rotation restrictions. Wheat, triticale, and oats may be planted 7 days after application; alfalfa, canola, field pea, sugar beet and potatoes 9 mo after application. Do not graze or harvest treated winter wheat for forage within 25 days of application, or harvest grain and straw within 60 days of application. Do not exceed one application of Huskie to winter wheat per year.
Site of action  (bromoxynil) Group 6: photosystem II inhibitor;(pyrasulfotole) Group 28: inhibits 4‑hydroxyphenylpyruvatedioxygenase (4-HPPD)
Chemical family  (bromoxynil) nitrile; (pyrasulfotole) isoxazole
•  pyraflufen (ET)
Rate  0.0008 to 0.002 lb ai/A (0.5 to 1.0 oz/A ET)
Time  Apply to winter wheat that is 6 to 8 inches tall up to jointing. Apply to seedling weeds that are less than 4 inches tall or less than 3 inches in diameter if in the rosette stage.
Remarks  For postemergence broadleaf weed control in winter wheat. May be tank-mixed with the synthetic auxin herbicides to broaden the weed control spectrum. Always apply with a methylated seed oil or nonionic surfactant at a rate of 0.5% v/v for optimum activity.
Caution  Do not tank-mix ET with products containing bromoxynil or severe wheat injury may result. Do not exceed 1 oz/A or two applications of ET per season. Do not graze wheat within 7 days of application or harvest wheat for hay within 21 days of application. The preharvest interval for grain is 60 days.
Site of action  Group 14: protoporphyrinogen oxidase inhibitor
Chemical family  Phenylpyrazole
•  2,4-D amine (several trade names) or
•  MCPA (several trade names)
Rate  0.75 lb ae/A
Time  Apply in spring when winter wheat has at least four tillers and 12 leaves but before jointing.
Remarks  Do not apply in the fall. Do not apply between jointing and dough stage of growth.
Site of action  (both) Group 4: synthetic auxin
Chemical family  (both) phenoxy acetic acid
•  dicamba (several trade names)
Rate  0.063 to 0.125 lb ae/A for early-season applications; up to 0.188 lb ae/A on fall-seeded wheat in western Oregon as a spring application only.
Time  For best performance, apply when weeds are in the two- to three-leaf stage and rosettes are less than 2 inches across. Applications must be before winter wheat jointing stage.
Remarks  Tank-mixing with other herbicides offers the best spectrum of weed control and herbicide resistant weed management. Consult product labels for rates and timing.
Site of action  Group 4: synthetic auxin
Chemical family  Benzoic acid 
•  chlorsulfuron (several trade names) +
•  another broadleaf herbicide with a different mode of action
Rate  0.008 to 0.016 lb ai/A
Time  Apply in fall or spring any time after the crop is in the two-leaf stage but before boot.
Remarks  Do not exceed 0.016 lb ai/A of chlorsulfuron in an 18-mo period.
Caution  Consult individual labels regarding crop rotation restrictions. Many crops may not be planted for 2 yr or longer after application.
Site of action  Group 2: acetolactate synthase (ALS) inhibitor
Chemical family  Sulfonylurea
•  chlorsulfuron + metsulfuron (several trade names) +
•  another broadleaf herbicide with a different mode of action
Rate  0.014 to 0.019 lb ai/A preemergence or fall postemergence; 0.009 to 0.014 lb ai/A spring postemergence. Do not exceed 0.019 lb ai/A of a chlorsulfuron + metsulfuron premix in an 18-mo period.
Time  Preemergence in fall or spring or any time after wheat is in the two-leaf stage but before boot stage.
Remarks  When applying postemergence, use 80% ai surfactant at 1 to 2 quarts/100 gal for best results. This combination effectively controls speedwells. Use when weeds are small and actively growing.
Caution  See label for crop rotation restrictions. Many crops cannot be planted for 2 yr or longer after application. Perennial and annual ryegrass and crimson clover may not be planted for 9 mo, barley and oats for 10 mo, or red clover for 15 mo after an application. No restrictions on rotations to wheat, rye, or triticale.
Site of action  (both) Group 2: acetolactate synthase (ALS) inhibitor
Chemical family  (both) sulfonylurea
•  thifensulfuron + tribenuron (several trade names)  +
•  another broadleaf herbicide with a different mode of action
Rate  0.014 to 0.028 lb ai/A
Time  Apply after crop is in the two-leaf stage through the boot stage.
Remarks  Results are best when weeds are young and actively growing. For best performance, apply when conditions include temperatures of 60°F or higher and adequate soil moisture before, during, and immediately after treatment. Use with an 80% ai nonionic surfactant at 2 pints/100 gal.
Caution  Wheat, barley, and oats may be replanted any time after application. Sugar beets and winter canola can be planted 60 days after application. All other crops can be planted 45 days after application.
Site of action  (both) Group 2: acetolactate synthase (ALS) inhibitor
Chemical family  (both) sulfonylurea
•  thifensulfuron (several trade names) +
•  another broadleaf herbicide with a different mode of action
Rate  0.014 to 0.028 lb ai/A plus nonionic surfactant
Time  After crop is in the two-leaf stage but before flag leaf is visible.
Remarks  Results are best when weeds are young and actively growing. For best performance apply when temperatures are 60°F or higher and soil moisture is adequate before, during, and immediately after treatment. Can be tank-mixed with grass herbicides. Include a nonionic surfactant of at least 80% ai at 1 quart/100 gal.
Caution  Do not let spray drift to adjacent crop or land. Do not apply during an air temperature inversion. Immediately after spraying, thoroughly clean chemical from mixing and spray equipment with an approved tank cleaner. Do not plant any crop other than wheat, barley, soybeans, field corn, or oats for 45 days after applying.
Site of action  Group 2: acetolactate synthase (ALS) inhibitor
Chemical family  Sulfonylurea
•  metsulfuron  (several trade names) +
•  another broadleaf herbicide with a different mode of action
Rate  0.004 lb ai/A
Time  Apply postemergence after wheat has two leaves but before boot stage.
Remarks  Metsulfuron controls a wide range of broadleaf weeds and inhibits Canada thistle growth.  For best results, add a nonionic surfactant of at least 80% ai at 1 to 2 quarts/100 gal. For weeds that are difficult to control, apply while they are actively growing and not more than 2 inches tall or in diameter. To broaden the spectrum of control, tank-mix with a suitable registered herbicide. Time application to coincide with recommendation for specific tank-mix partner.
Caution  Metsulfuron can persist in soil. Carefully follow label instructions about crop rotation restrictions.
Site of action  Group 2: acetolactate synthase (ALS) inhibitor
Chemical family  Sulfonylurea
•  prosulfuron (Peak) +
•  another broadleaf herbicide with a different mode of action
Rate  0.009 to 0.018 lb ai/A (0.25 to 0.5 oz/A Peak)
Time  Apply postemergence from the three-leaf to the second-joint stage of growth.
Remarks  Results are best when weeds are young and actively growing. Apply with nonionic surfactant of at least 80% ai at 1 to 2 quarts/100 gal or a crop oil concentrate of at least 12% emulsifier at 1 to 4 pints/A.
Caution  Carefully follow label instructions on crop rotation restrictions. Do not let spray drift to nontarget crops. See label for cautions on tank-mix or sequential applications with organophosphate insecticides and applications just before or during adverse conditions such as cold weather.
Site of action  Group 2: acetolactate synthase (ALS) inhibitor
Chemical family  Sulfonylurea
•  triasulfuron + dicamba (Rave)
Rate  0.005 to 0.022 lb ai/A triasulfuron + 0.034 to 0.138 lb ai/A dicamba (1 to 4 oz/A Rave)
Time  Apply to winter wheat postemergence from emergence up to jointing.
Remarks  Results are best when weeds are young and actively growing. Apply with nonionic surfactant of at least 80% ai at 1 to 2 quarts/100 gal or a crop oil concentrate of at least 12% emulsifier at 1 to 4 pints/A.
Caution  Carefully follow label instructions on crop rotation restrictions. Do not let spray drift to nontarget crops. See label for cautions on tank-mix or sequential applications with organophosphate insecticides and applications just before or during adverse conditions such as cold weather. Follow label instructions on grazing restrictions.
Site of action  (triasulfuron) Group 2: acetolactate synthase (ALS) inhibitor; (dicamba) Group 4: synthetic auxin
Chemical family  (triasulfuron) sulfonylurea; (dicamba) benzoic acid
 •  florasulam + MCPA (Orion)
Rate  0.004 lb ai/A florasulam + 0.31 lb ai/A MCPA (17 oz/A Orion)
Time  Apply to winter wheat postemergence from the three-leaf stage up to jointing.
Remarks  Results are best when weeds are young and actively growing. Orion will control chickweeds, wild buckwheat, mustard spp., and bedstraw and can be tank-mixed with other grass and broadleaf herbicides to broaden the weed control spectrum.
Caution  See label for specific crop rotation restrictions. For most crops the plant-back interval is between 3 and 9 mo. Do not graze wheat within 7 days of an Orion application, and do not harvest wheat within 60 days of an application.
Site of action  (florasulam) Group 2: acetolactate synthase (ALS) inhibitor; (MCPA) Group 4: synthetic auxin
Chemical family  (florasulam) triazolopyrimidine; (MCPA) phenoxyacetic acid
•  carfentrazone (Aim EC)
Rate  0.008 to 0.031 lb ai/A (0.5 to 2 oz/A Aim EC)
Time  For emerged winter wheat, use 0.5 to 1 oz/A Aim EC. Use higher rates when treating more mature weeds or dense vegetative growth. Do not exceed 0.031 lb ai/A of Aim per season. Apply to emerged and actively growing weeds. Apply to wheat up to jointing stage. For best performance, apply to weeds up to 4 inches high and rosettes less than 3 inches across.
Remarks  Aim is excellent for controlling bedstraw and speedwells. Use with an 80% ai nonionic surfactant at 2 pints/100 gal.
Caution  Plant registered crops any time after applying Aim. Root and leafy vegetables may be planted 30 days after application and all other crops 12 mo after application. Crop injury may increase with tank-mixtures; see label for tank-mixing guidelines.
Site of action  Group 14: protoporphyrinogen oxidase inhibitor
Chemical family  Triazinone
•  carfentrazone + 2,4-D (Rage D-Tech) 
Rate  0.38 to 0.76 lb ai/A (8 to 16 fl oz/A Rage D-Tech)
Time  Apply from 3-tiller stage to jointing of grain and when weeds are up to 4 to 6 inches tall.
Remarks  Include a nonionic surfactant at 0.25% v/v (2 pints/100 gal spray solution). A high-quality sprayable liquid nitrogen fertilizer may be used at 2% to 4% v/v or AMS at 2 to 4 lb/A in addition to the nonionic surfactant. Adjuvants other than nonionic surfactants are not recommended. Consult label for more information.
Caution  Do not exceed 1.51 lb ai/acre Rage D-Tech per year. Tank-mixes with EC or ester formulations of other herbicides may increase leaf speckling. Do not apply to foliage wet from dew, rain, or irrigation, or crop injury may increase.
Site of action  (carfentrazone) Group 14: protoporphyrinogen oxidase inhibitor; (2,4-D) Group 4: synthetic auxin
Chemical family  (carfentrazone) triazinone; (2,4-D) phenoxy acetic acid
•   fluroxypyr (Starane Ultra)
Rate  0.10 to 0.245 lb ai/A fluroxypyr (0.3 to 0.7 pint/A Starane Ultra)
Time  For best performance, apply to emerged and actively growing broadleaf weeds less than 4 inches high or 1 inch wide. Use higher rate for susceptible broadleaf weeds up to 8 inches tall. Only weeds that have emerged at time of application will be controlled. Apply to two-leaf winter wheat up to flag leaf emergence.
Remarks  Do not exceed 0.7 pints/A per growing season.
Caution  Do not harvest winter wheat for hay or silage from treated area within 7 days of application. Preharvest interval is 40 days.
Site of action  Group 4: synthetic auxin
Chemical family  Pyridine
•  fluroxypyr + bromoxynil (Starane NXT)
Rate  0.0625 to 0.125 lb ai/A fluroxypyr + 0.25 to 0.5 lb ai/A bromoxynil (14 to 27.4 oz/A Starane NXT)
Time  For best performance, apply to emerged and actively growing weeds up to 4 to 8 inches tall depending on rate. Apply to wheat from three-leaf stage through flag leaf emergence.
Remarks  Provides control of broadleaf weeds including kochia, wild buckwheat, Russian thistle, and sunflower. Tank-mix compatible with MCPA, thifensulfuron or 2,4-D and most grass herbicides.
Caution  Any rotational crop may be planted 120 days after application. Do not apply within 45 days of wheat harvest or allow livestock to graze within 45 days of application. Do not apply with fungicides containing strobilurin chemistry.
Site of action  (fluroxypyr) Group 4: synthetic auxin; (bromoxynil) Group 6: photosystem II inhibitor
Chemical family  (fluroxypyr) pyridine; (bromoxynil) nitrile
breakhere  WINTER WHEAT―West of Cascades―Broadleaf Weeds and Canada Thistle 
•  dicamba (several trade names) +
•  MCPA (several trade names) 
Oregon only
Rate  0.125 to 0.188 lb ae/A dicamba + 0.75 lb ae/A MCPA
Time  Apply in spring when winter wheat has at least four tillers but before it begins to joint.
Remarks  Controls many broadleaf weeds and kills or suppresses Canada thistle.
Site of action  (both) Group 4: synthetic auxin
Chemical family  (dicamba) benzoic acid; (MCPA) phenoxy acetic acid
•  tribenuron (several trade names)
Rate  0.008 to 0.016 lb ai/A
Time  Apply after crop is in the two-leaf stage but before the flag leaf is visible.
Remarks  Results are best on young, actively growing weeds. For best performance, apply when temperatures are 60°F or higher and moisture is adequate before, during, and immediately after treatment. The 0.016 lb ai/A rate is effective on Canada thistle; apply at 4 to 12 inches of growth. Use with an 80% ai nonionic surfactant at 2 pints/100 gal.
Caution  Replant wheat, barley, and oats any time after application. Plant sugar beets, winter rape, and canola 60 days after application, and all other crops 45 days after application.
Site of action  Group 2: acetolactate synthase (ALS) inhibitor
Chemical family  Sulfonylurea
•  clopyralid (Stinger)
Rate  0.094 to 0.125 lb ae/A (0.25 to 0.33 pint/A Stinger)
Time  Apply from three-leaf up to early boot stage of winter wheat growth. Apply to actively growing weeds. Only weeds emerged at the time of application will be affected.
Remarks  To control perennial weeds such as Canada thistle, use the 0.33-pint/A rate.
Caution  Do not exceed 0.67 pint/A per crop year. Plant wheat, barley, oats, grasses, field corn, or sugar beets any time after treatment. See label for crop rotation restrictions on other crops. Do not apply by air.
Site of action  Group 4: synthetic auxin
Chemical family  Pyridine
•  clopyralid + 2,4-D (Curtail)
Rate  0.095 to 0.126 lb ae clopyralid + 0.5 to 0.67 lb ae/A 2,4-D amine (2 to 2.66 pints/A Curtail)
Time  Apply in spring to actively growing weeds after winter wheat begins tillering up to jointing stage.
Remarks  This combination is particularly effective on members of the sunflower family such as Canada thistle and mayweed. Controlling tough winter annual weeds such as corn gromwell and fiddleneck requires tank-mixing with other herbicides. Check Curtail label for details on mixtures. For Canada thistle, apply after most basal leaves emerge but before bud stage.
Caution  Do not plant wheat, barley, oats, grasses, or field corn within 30 days after applying Curtail. Do not plant sugar beets, including beets grown for seed, in the same growing season after applying Curtail. See label for crop rotation restrictions on other crops.
Site of action  (both) Group 4: synthetic auxin
Chemical family  (clopyralid) pyridine; (2,4-D) phenoxy acetic acid
•  clopyralid + MCPA (Curtail M)
Rate  0.092 to 0.122 lb ae/A clopyralid + 0.5 to 0.69 lb ae/A MCPA (1.75 to 2.33 pints/A Curtail M)
Time  Apply in spring to actively growing weeds from the three-leaf up to jointing stage of wheat growth. Only weeds emerged at the time of application will be affected.
Remarks  For Canada thistle, apply after most basal leaves emerge but before bud stage.
Caution  Do not plant wheat, barley, oats, grasses, or corn within 30 days after applying Curtail M. Do not plant sugar beets in the same growing season after Curtail M. See label for crop rotation restrictions on other crops.
Site of action  (both) Group 4: synthetic auxin
Chemical family  (clopyralid) pyridine; (MCPA) phenoxy acetic acid
•  aminopyralid + fluroxypyr (CleanWave)
Rate  0.13 lb ai/A fluroxypyr + 0.009 lb ai/A aminopyralid (14 oz/A CleanWave)
Time  For best performance, apply to emerged and actively growing broadleaf weeds.  Apply to winter wheat from three-leaf stage through jointing.
Remarks  Controls broadleaf weeds including kochia, wild buckwheat and prickly lettuce, including ALS resistant biotypes of these species. The 14‑oz rate also suppresses many perennial weeds. Tank-mix compatible with a wide variety of broadleaf herbicides and most grass herbicides, but do not tank-mix with Osprey or Osprey + MCPA.
Caution  See label for plant-back restrictions on other crops. Intervals range from 0 to 24 mo. There are no grazing restrictions after applying CleanWave. Preharvest interval for haying wheat is 14 days, 50 days for grain and straw.
Site of action  (both) Group 4: synthetic auxin
Chemical family  (both) pyridine
•  fluroxypyr + clopyralid (several trade names) 
Rate  0.094 to 0.125 lb ai/A fluroxypyr + 0.094 to 0.125 lb ai/A clopyralid 
Time  For best performance, apply to emerged and actively growing weeds 4 to 8 inches tall depending on rate. Apply to winter wheat from three-leaf stage through flag leaf emergence.
Remarks  Controls broadleaf weeds including kochia, wild buckwheat, Canada thistle, and prickly lettuce. Tank-mix compatible with MCPA, thifensulfuron or 2,4-D, and most grass herbicides.
Caution  See label for rotation restrictions on other crops. Do not allow livestock to graze treated areas or harvest forage within 7 days of application. Preharvest interval for grain or straw is 40 days.
Site of action  (both) Group 4: synthetic auxin
Chemical family  (both) pyridine
WINTER WHEAT―West of Cascades―Preharvest Weed Control
•  2,4-D (several trade names)
Rate  0.5 to 1.4 lb ae/A
Time  Apply when grain is in the hard dough stage and the green color is gone from stem nodes.
Remarks  Controls weeds that will interfere with harvest and suppresses perennial weeds. Preharvest interval is 7 days.
Caution  Do not apply to winter wheat grown for seed.
Site of action  Group 4: synthetic auxin 
Chemical family  Phenoxy acetic acid
•  dicamba (several trade names)
Rate  0.25 lb ae/A
Time  Apply when grain is in the hard dough stage and the green color is gone from stem nodes.
Remarks  To control weeds that will interfere with harvest or to suppress perennial weeds. Not all dicamba labels include this use. Preharvest interval is 7 days. 
Caution  Do not apply to winter wheat grown for seed.
Site of action  Group 4: synthetic auxin
Chemical family  Benzoic acid
•  dicamba (several trade names) +
•  2,4-D (several trade names)
Rate  0.25 lb ae dicamba/A + 0.5 to 1 lb ae/A 2,4-D
Time  Apply when grain is in the hard dough stage and the green color is gone from stem nodes.
Remarks  To control weeds that will interfere with harvest or to suppress perennial weeds. Preharvest interval is 7 days. Not all dicamba labels include this use.
Caution  Do not apply to winter wheat grown for seed.
Site of action  (both) Group 4: synthetic auxin
Chemical family  (dicamba) benzoic acid; (2,4-D) phenoxy acetic acid
•  carfentrazone (Aim EC)
Rate  0.016 to 0.031 lb ai/A (1 to 2 oz/A Aim EC)
Time  Apply when winter wheat is mature and the grain has begun to dry down.
Remarks  A nonionic surfactant, methylated seed oil, or crop oil concentrate is required. Good spray coverage is essential for satisfactory weed control. Repeat application if necessary.
Caution  See label for tank-mixing guidelines, precautions, and crop rotation restrictions.
Site of action  Group 14: protoporphyrinogen oxidase inhibitor
Chemical family  Triazinone
•  carfentrazone + 2,4-D (Rage D-Tech) 
Rate  0.76 to 1.51 lb ai/A (16 to 32 fl oz/A Rage D-Tech)
Time  Apply when grain is in hard dough stage to control weeds that will interfere with harvest.
Remarks  A nonionic surfactant, methylated seed oil, or crop oil concentrate is required. Coverage is essential for satisfactory performance.
Caution  Do not exceed 1.51 lb ai/A Rage D-Tech per year. Do not apply less than 7 days before harvest. Do not feed straw to livestock. Do not graze dairy or meat animals being finished for slaughter for 14 days after application.
Site of action  (carfentrazone) Group 14: protoporphyrinogen oxidase inhibitor; (2,4-D) Group 4: synthetic auxin
Chemical family  (carfentrazone) triazinone; (2,4-D) phenoxy acetic acid
•   glyphosate (several trade names)
Rate  0.38 to 0.75 lb ae/A
Time Apply when grain is in the hard dough stage and the green color is gone from stem nodes.
Remarks  To control weeds that will interfere with harvest or to suppress perennial weeds. Add an 80% ai nonionic surfactant. Preharvest interval is 7 days. Not all glyphosate labels include this use.
Caution  Do not apply to winter wheat grown for seed. 
Site of action  Group 9: inhibits EPSP synthase 
Chemical family  None generally accepted
WINTER WHEAT―West of Cascades―Clearfield Wheat System
•  imazamox (Beyond) 
Clearfield wheat only
Rate  0.031 to 0.047 lb ai/A (4 to 6 oz/A Beyond)
Time  Apply postemergence to Clearfield wheat after tiller initiation but before jointing. Can be applied in fall or winter or in spring for winter or spring annual weed control. Apply when most of actively growing annual grass weeds are in the four- to five-leaf stage and broadleaf weeds are less than 3 inches tall and actively growing.
Remarks  Adding an adjuvant (nonionic surfactant) and a liquid nitrogen fertilizer or ammonium sulfate solution is required.
Caution  Apply to Clearfield wheat varieties only. Temporary height reduction or slight leaf yellowing may occur after application; effects can be more pronounced if the crop is under environmental stress. Do not tank-mix with sulfonylurea herbicides (such as Finesse, Ally, or Harmony) due to potential crop response or weed-control antagonism. Apply Beyond a maximum of 2 out of 4 yr. Do not plant Clearfield wheat continuously. There are no restrictions on feeding or grazing wheat forage and hay after applying Beyond. Some rotation crops cannot be planted within 26 mo of application; see updated label for crop rotation restrictions.
Site of action  Group 2: acetolactate synthase (ALS) inhibitor
Chemical family  Imidazolinone
•  imazamox + MCPA ester (Clearmax)
Clearfield wheat only
Rate  0.031 to 0.047 lb ai/A imazamox + 0.23 to 0.35 lb ai/A MCPA ester (12 to 18 oz/A Clearmax)
Time  Apply postemergence to Clearfield wheat after tiller initiation but before jointing. Can be applied in fall or winter or in spring for winter or spring annual weed control. Apply when most of actively growing annual grass weeds are in the four- to five-leaf stage and broadleaf weeds are less than 3 inches tall and actively growing.
Remarks  Adding an adjuvant (nonionic surfactant) and a liquid nitrogen fertilizer or ammonium sulfate solution is required.
Caution  Apply to Clearfield wheat varieties only. Temporary height reduction or slight leaf yellowing may occur after application; effects can be more pronounced if the crop is under environmental stress. Do not tank-mix with sulfonylurea herbicides (such as Finesse, Ally, or Harmony) due to potential crop response or weed- control antagonism. Apply Clearmax a maximum of 2 out of 4 yr. Do not plant Clearfield wheat continuously. Do not forage or graze meat animals on treated areas within 7 days of slaughter. Do not forage or graze dairy animals on treated areas within 7 days after treatment. Some rotation crops cannot be planted within 26 mo of application; see updated label for crop rotation restrictions.
Site of action  (imazamox) Group 2: acetolactate synthase (ALS) inhibitor; (MCPA) Group 4: synthetic auxin
Chemical family  (imazamox) imidazolinone; (MCPA) phenoxy acetic acid
breakhere 
Herbicide Effectiveness on Weeds in Wheat
(West of Cascades) 
Weed Family	thifensulfuron+ tribenuron 	chlorsulfuron+ metsulfuron 	2,4-D	MCPA	dicamba	bromoxynil	metribuzin	diuron	2, 4-D+ clopyralid 	prosulfuron	metsulfuron	clopyralid	
Amaranth
Amaranth, Powell
Amaranthus powellii	
G	
G	
G	
G	
G	
F	
―	
G	
―	
―	
―	
―	
Pigweed, redroot
Amaranthus retroflexus	G	G	G	G	G	F	―	G	―	G	G	G	
Borage
Fiddleneck, coast
Amsinckia intermedia	
G	
G	
F	
F	
―	
G	
―	
G	
―	
―	
―	
―	
Buckwheat
Buckwheat, wild
Polygonum convolvulus	
G	
G	
F	
F	
G	
G	
F	
F	
G	
―	
G	
G	
Dock, broadleaf
Rumex obtusifolius	G	G	G	F	G	P	―	F	―	�\	�\	�\	
Dock, curly
Rumex crispus	G	G	G	F	G	P	―	F	G	―	�\	G	
Knotweed, prostrate
Polygonum aviculare	G	G	F	P	G	F	F	F	―	�\	G	―	
Ladysthumb
Polygonum persicaria	―	G	G	F	G	G	P	F	F	―	G	G	
Sorrel, red
Rumex acetosella	―	F	P	P	G	P	―	F	G	―	�\	G	
Buttercup
Buttercup, corn
Ranunculus arvensis	
―	
―	
G	
G	
G	
―	
―	
―	
―	
―	
―	
―	
Buttercup, creeping
Ranunculus repens	G	G	F	G	G	―	�\	�\	�\	�\	�\	�\	
Buttercup, western field
Ranunculus occidentalis	―	�\	G	G	G	―	�\	�\	�\	�\	�\	�\	
Carrot
Bur chervil
Anthriscus scandicina	
G	
G	
P	
G	
―	
P	
―	
P	
―	
―	
―	
―	
Carrot, wild
Daucus carota	G	G	F	F	P	F	―	P	―	P-F	P-F	―	
Cucumber
Cucumber, western wild
Marah oreganus	
―	
―	
P	
P	
P	
P	
P	
P	
―	
―	
―	
―	
Evening Primrose 
Willowweed, panicle
Epilobium paniculatum	
―	
―	
P	
P	
―	
―	
G	
G	
―	
―	
―	
―	
Figwort
Mullein, common
Verbascum thapsus	
G	
―	
P	
P	
―	
―	
―	
―	
―	
―	
―	
―	
Mullein, moth
Verbascum blattaria	―	�\	F	P	―	�\	�\	�\	�\	�\	�\	�\	
Speedwell, birdseye
Veronica persica	―	F	P	P	P	F	G	P	―	�\	�\	�\	
Speedwell, ivyleaf
Veronica hederifolia	G	F	P	P	P	F	G	P	―	�\	�\	�\	
Speedwell, purslane
Veronica peregrina	G	G	F	P	P	―	G	P	―	�\	�\	�\	
Toadflax, yellow
Linaria vulgaris	―	�\	P	P	―	�\	�\	�\	�\	�\	�\	�\	
Geranium
Filaree, redstem
Erodium cicutarium	
G	
G	
F	
F	
―	
P	
G	
F	
―	
―	
G	
―	
Geranium, cutleaf
Geranium dissectum	G	G	P	G	―	�\	G	G	―	�\	�\	�\	
Geranium, dovefoot
Geranium molle	―	G	P	P	―	�\	G	G	―	�\	�\	�\	
Goosefoot
Lambsquarters, common
Chenopodium album	
F	
G	
G	
G	
G	
G	
F	
G	
―	
G	
G	
G	
Lily
Garlic, wild
Allium vineale	
G	
F	
F	
P	
F	
P	
P	
P	
―	
―	
―	
―	
Onion, wild
Allium amplectens	G	F	F	P	F	P	P	P	―	�\	�\	�\	
Madder
Bedstraw, catchweed
Galium aparine	
F	
F	
P	
P	
F	
F	
P	
P	
―	
―	
―	
―	
Bedstraw, corn
Galium tricorne	―	�\	P	P	―	F	P	P	―	�\	�\	�\	
Madder, field
Sherardia arvensis	―	�\	P	P	―	�\	�\	�\	�\	�\	�\	�\	
Mallow 
Mallow, common
Malva neglecta	
G	
G	
F	
P	
―	
P	
P	
P	
―	
―	
―	
―	
Mallow, dwarf
Malva rotundifolia	―	�\	F	P	―	�\	�\	�\	�\	�\	�\	�\	
Mallow, little
Malva parviflora	―	�\	F	P	―	�\	�\	�\	�\	�\	�\	�\	
Mint
Deadnettle, red
Lamium purpureum	
G	
G	
P	
F	
―	
P	
G	
G	
―	
―	
―	
―	
Healall
Prunella vulgaris	―	�\	G	P	―	�\	�\	�\	�\	�\	�\	�\	
Henbit
Lamium amplexicaule	G	G	P	F	―	P	G	G	―	G	G	―	
Morningglory
Bindweed, field
Convolvulus arvensis	
P	
P	
F	
F	
F	
P	
P	
P	
―	
F-G	
―	
―	
Bindweed, hedge
Convolvulus sepium	P	―	G	G	G	P	P	P	―	�\	�\	�\	
Mustard
Bittercress, little
Cardamine oligosperma	
G	
G	
G	
G	
―	
F	
G	
G	
―	
―	
―	
―	
Mustard, black
Brassica nigra	G	G	G	G	P	G	G	G	―	G	G	―	
Mustard, Indian
Brassica juncea	G	G	G	G	P	P	―	G	―	G	G	―	
Mustard, wild
Brassica kaber	G	G	G	G	P	F	G	G	―	G	G	G	
Radish, common
Raphanus sativus	G	G	G	G	P	F	G	G	―	�\	�\	�\	
Radish, wild
Raphanus raphanistrum	G	G	G	G	P	F	G	G	―	�\	�\	G	
Rocket, yellow
Barbarea vulgaris	G	G	G	G	―	P	G	G	―	�\	�\	�\	
Shepherdspurse
Capsella bursa-pastoris	G	G	G	G	―	F	G	G	―	G	―	G	
Turnip, wild
Brassica campestris	G	G	G	G	P	G	G	G	―	�\	�\	�\	
Wort, whitlow
Draba verna	―	G	―	�\	�\	�\	G	G	―	�\	�\	�\	
Nightshade
Nightshade, black
Solanum nigrum	
P	
P	
F	
F	
―	
―	
P	
G	
G	
―	
―	
G	
Nightshade, hairy
Solanum sarrachoides	P	P	F	F	―	�\	P	G	G	―	�\	G	
Pea
Vetch, common
Vicia sativa	
G	
G	
G	
G	
G	
F	
P	
P	
G	
―	
―	
G	
Vetch, hairy
Vicia villosa	G	F	G	G	G	F	P	P	―	�\	�\	G	
Vetch, narrowleaf
Vicia angustifolia	―	�\	G	F	G	F	P	P	―	�\	�\	G	
Phlox
Gilia, field
Gilia capitata	
―	
F	
―	
―	
―	
―	
G	
G	
―	
―	
―	
―	
Gilia, skunkweed
Navarretia squarrosa	―	G	―	�\	�\	�\	G	G	―	�\	�\	�\	
Gilia, woolly
Navarretia intertexta	―	�\	�\	�\	�\	�\	G	G	―	�\	�\	�\	
Pink
Bouncing bet
Saponaria officinalis	
―	
―	
P	
P	
―	
P	
P	
P	
―	
―	
―	
―	
Chickweed
Stellaria media	G	G	F	P	G	P	G	G	―	G	G	―	
Chickweed, mouseear
Cerastium vulgatum	G	G	F	P	F	P	G	G	―	�\	�\	�\	
Chickweed, sticky
Cerastium viscosum	―	G	P	P	F	P	G	G	―	G	G	―	
Knawel
Scleranthus annuus	―	�\	P	P	G	P	G	G	―	�\	�\	�\	
Spurry, corn
Spergula arvensis	―	G	P	F	―	P	G	G	―	�\	�\	�\	
Plantain
Plantain, buckhorn
Plantago lanceolata	
―	
―	
G	
G	
P	
―	
―	
P	
―	
―	
F	
G	
Poppy 
Poppy, California
Eschscholtzia californica	
―	
―	
G	
G	
―	
―	
―	
―	
―	
―	
―	
―	
Primrose
Pimpernel, scarlet
Anagallis arvensis	
―	
G	
G	
G	
―	
P	
G	
G	
―	
―	
―	
―	
Purslane
Minerslettuce
Montia perfoliata	
G	
G	
P	
P	
―	
F	
G	
G	
―	
―	
―	
―	
Purslane, redmaids rock
Calandrinia ciliata	―	�\	G	G	―	�\	G	G	―	�\	�\	�\	
Rose
Burnet, small
Sanguisorba minor	
―	
―	
―	
―	
―	
―	
―	
G	
―	
―	
―	
―	
Cinquefoil, silverweed
Potentilla anserina	―	�\	P	P	―	�\	�\	P	―	�\	�\	�\	
Rush
Toadrush
Juncus bufonius	
―	
―	
G	
G	
―	
―	
―	
G	
―	
―	
―	
―	
Sunflower
Artichoke, Jerusalem
Helianthus tuberosus	
―	
―	
G	
G	
G	
P	
P	
―	
G	
―	
―	
G	
Catsear, spotted
Hypochoeris radicata	G	G	G	G	―	�\	�\	�\	�\	�\	�\	�\	
Chicory
Cichorium intybus	―	�\	G	G	―	�\	�\	�\	�\	�\	�\	�\	
Cocklebur, heartleaf
Xanthium strumarium	―	�\	G	F	G	―	�\	G	G	―	�\	�\	
Sunflower
Cornflower
Centaurea cyanus	
―	
F	
G	
F	
―	
F	
―	
G	
G	
―	
―	
G	
Cudweed, low
Gnaphalium uliginosum	―	�\	P	P	―	�\	�\	�\	�\	�\	�\	�\	
Cudweed, purple
Gnaphalium purpureum	―	G	P	P	―	�\	�\	�\	�\	�\	�\	�\	
Daisy, oxeye
Chrysanthemum leucanthemum	―	�\	F	F	―	�\	�\	F	G	―	�\	G	
Dandelion, common
Taraxacum officinale	G	G	G	G	―	P	―	�\	G	―	F-G	G	
Groundsel, common
Senecio vulgaris	G	G	P	P	―	G	F	F	G	―	G	G	
Hawkbit, rough
Leontodon nudicaulis	―	�\	G	G	―	�\	�\	�\	�\	�\	�\	�\	
Hawksbeard, bristly
Crepis setosa	―	G	P	P	P	―	G	G	G	―	�\	G	
Lettuce, prickly
Lactuca serriola	G	G	G	G	G	F	G	G	G	G	F-G	G	
Lettuce, willowleaf
Lactuca saligna	―	�\	G	G	―	�\	�\	�\	�\	�\	�\	�\	
Mayweed (Dog fennel)
Anthemis cotula	G	G	F	P	G	G	F	G	G	G	G	G	
Nipplewort
Lapsana communis	G	G	P	P	―	G	―	G	―	�\	�\	�\	
Pineappleweed
Matricaria matricarioides	G	G	F	P	F	G	―	F	G	―	�\	G	
Salsify, common
Tragopogon porrifolius	―	�\	G	―	F	―	�\	�\	�\	�\	�\	�\	
Salsify, meadow
Tragopogon pratensis	―	G	G	―	F	―	�\	�\	G	―	�\	G	
Salsify, western
Tragopogon major	―	�\	G	―	F	―	�\	�\	�\			�\	
Sowthistle, annual
Sonchus oleraceus	G	G	G	G	G	F	G	G	G	―	�\	G	
Sowthistle, spiny
Sonchus asper	G	―	G	G	G	F	G	G		―	�\		
Tarweed, cluster
Madia glomerata	―	�\	�\	�\	�\	G	―	�\	�\	�\	�\	�\	
Tarweed, Chilean
Madia sativa	―	�\	P	P	―	G	―	�\	�\	�\	�\	�\	
Thistle, bull
Cirsium vulgare	F	F	G	G	―	�\	�\	G	―	�\	�\	�\	
Thistle, Canada
Cirsium arvense	G	G	F	F	F	P	P	P	G	F	―	G	
Yarrow, common
Achillea millefolium	―	�\	P	P	F	P	―	P	―	�\	�\	�\	

     breakhere 
 HERBICIDE EFFECTIVENESS ON WEEDS IN WHEAT WEST OF CASCADES (contd.)
  Grasses	 chlorsulfuron + metsulfuron	 imazamethabenz	 diclofop	 fenoxaprop	triallate	 diuron	flucarbazone
	 metribuzin	
Barnyardgrass 
Echinochloa crus-galli	P	P	G	G	P	G	G	F	
Blackgrass
Alopecurus myosuriodes	G	P	G	G	P	P	―	G	
Bluegrass, annual
Poa annua	F	P	P	P	P	G	―	F	
Brome, California
Bromus carinatus	P	P	P*	P	P	P	P	P	
Brome, ripgut
Bromus rigidus	P	P	G*	P	F	P	P	F	
Cheat
Bromus secalinus	P	P	F* 	P	F	P	P	F	
Chess, soft
Bromus mollis	P	P	F*	P	F	P	―	F	
Fescue, rattail
Vulpia myuros	P	P	P	P	P	G	―	G	
Foxtail, green
Setaria viridis	P	P	G	G	P	G	G	P	
Oat, wild
Avena fatua	P	G	G	G	F	P	G	P	
Ryegrass, Italian
Lolium multiflorum	F	P	G	P	F	F	G	F	
Witchgrass
Panicum capillare	P	P	F	P	P	F	G	F