Weed Management in Brassica and Other Oilseed Crops

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Weed Management in Brassica and Other Oilseed
Crops

• Joe Yenish
• Extension Weed Scientist
• Washington State University

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Canola/Rapeseed

• Sonalan
• Preplant Incorporated
• 5.5 9.5 Sonalan 10G/A
• 1.5-2.5 pts Sonalan HFP/A
• Treflan
• Preplant Incorporated
• 5 10 Treflan TR10/A
• 1 2 pints Treflan HFP/A

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Canola/Rapeseed

• Grasses
• Assure II
• 5 to 12 oz/appl.
• lt18 oz/season
• Poast
• 1 to 2.5 pts/appl.
• lt5 pts/season
• Select 2EC
• lt6 oz/appl.
• lt16 oz/season

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Broadleaf Weeds

• Stinger, Others (Clopyralid)
• Postemergence
• 1 application per crop
• 2 to 6 lf crop stage
• 0.25 to 0.5 pt/A
• May be tankmixed
• Could compromise rotationLegumes

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Herbicide-Resistant Weed Management Systems

• GMOs
• LibertyLink
• Roundup Ready
• NonGMOs
• Clearfield
• ExpressSun
• Sunflowers only

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Herbicide Resistant Canola

• Only Clearfield Canola may be planted in the next
  season following Pursuit at labeled rates

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Herbicide-Resistant CanolaClearfield

• Clearfield Seed
• Beyond herbicide
• Only for use in Clearfield Canola, Sunflower, or
  Wheat
• Apply 4 oz Beyond/A surfactant N fertilizer
• Label recommends soil applied grass herbicide
  prior to Beyond
• Early POST but before canola bloom

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Herbicide-Resistant CanolaRoundup Ready

• Roundup Ready Seed
• Roundup and other glyphosate herbicides
• Glyphosate only
• Roundup Original MAX (4.5 a.e./gal.)
• Spring canola
• Single application
• 11 to 16 oz./A
• Sequential
• 11 11 oz/A
• Emerge to 6 lf canola

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Roundup Ready Canola

• Winter Canola
• Single application
• 16 to 22 oz./A Fall
• Sequential
• 11 to 22 oz/A Fall 11 to 22 oz/A Spr.
• Emerge to bolting canola

• Spring Canola
• Up to 44 oz preplant, planting, preemergence
• Up to 22 oz POST
• Winter Canola
• Up to 44 oz preplant, planting, preemergence
• Up to 44 oz POST

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Herbicide-Resistant CanolaLibertyLink

• LibertyLink Seed
• Liberty herbicide
• Glufosinate
• 28 to 34 oz./A per application
• Sequential 20 oz./A plus 20 oz./A
• Do not exceed 68 oz/A per crop
• 70 d plantback to wheat, barley,triticale

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Oilseed crops

• Mustard
• Select 2EC
• Safflower
• Pree
• Eptam
• Sonalan
• Dual Mag.
• Treflan
• POST
• Poast
• Select

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Sunflower

• PREE and PrePlant
• Prowl
• Dual
• Treflan
• Sonalan
• Eptam
• Spartan
• Micro-Tech

• POST
• Select
• Assure II
• Poast
• Express
• Hybrids with DuPont ExpressSUN trait
• Beyond
• Clearfield Hybrids

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Herbicide Carryover

• PNW Extension Bulletin 571 (PNW 571)
• Plantback Restrictions for Herbicides Used in the
  Dryland Wheat Production Areas of the Pacific
  Northwest. Hanson, Rauch, and Thill
• 4/hard copy Free PDF Download
• http//info.ag.uidaho.edu/pdf/PNW/PNW0571.pdf

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Herbicide PersistencePlantback Restriction

• Persistence of herbicides depend upon
• Rate
• ½ Life
• Repeated use
• Herbicide availability
• Plantback restriction depends upon above plus
• Sensitivity of the crop

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Herbicide Half-life

• Length of time required for one half of the
  original herbicide application to dissipate
• Determined by herbicide physical characters and
  environmental factors
• Moisture
• pH
• Soil texture
• Soil organic matter

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Half-life of two sulfonylurea herbicides
40 d
12 d
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Range of experimental half life of Pursuit
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Herbicide Carryover

• When rotating to canola
• Herbicide families of primary concern (ALS
  Inhibitors Group 2)
• Imidazolinones (IMIs)
• Assert, Pursuit, Beyond
• Sulfonylurea (SUs)
• Ally, Amber, Express, Glean, Harmony GT,
  Maverick, Osprey, Peak
• Sulfonylaminocarbonyltriazolinones
• Everest, Olympus

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Canola plantback restrictions - IMI herbicides
Herbicide Plantback Notes
Assert 15 mo. Clearfield Canola may be planted the season following application
Clearfield Canola may be planted the season following application

Pursuit 40 mo. MUST SUCCESSFULLY COMPLETE BIOASSAY
Clearfield Canola may be planted the season following application
Beyond/Raptor 26 mo. Clearfield Canola may be planted anytime

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Questions

• Extension Bulletins
• PNW 0437
• Herb. Res. Weeds Their Mgmt.
• PNW 0571
• Plantback Restrictions
• PNW 0572
• Mgmt. Strategies for Prev. Herb. Resist. Grass
  Weeds in Clearfield Wheat Systems
• http//ext.wsu.edu/
• http//www.uidaho.edu/extension/

• Joe Yenish
• 509-335-2961
• yenish_at_wsu.edu
• http//css.wsu.edu/weed_science