Weed Management in Brassica and Other Oilseed Crops Joe Yenish Extension Weed Scientist Washington State University

Canola/Rapeseed Sonalan Preplant Incorporated 5.5 – 9.5 # Sonalan 10G/A pts Sonalan HFP/A Treflan Preplant Incorporated 5 – 10 # Treflan TR10/A 1 – 2 pints Treflan HFP/A

Canola/Rapeseed Grasses Assure II 5 to 12 oz/appl. <18 oz/season Poast 1 to 2.5 pts/appl. <5 pts/season Select 2EC <6 oz/appl. <16 oz/season

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 rotation~Legumes

Herbicide-Resistant Weed Management Systems GMO’s LibertyLink ® Roundup Ready ® NonGMO’s Clearfield ® ExpressSun™ Sunflowers only

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

Herbicide-Resistant Canola Clearfield 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

Herbicide-Resistant Canola Roundup 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 oz/A Emerge to 6 lf canola

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

Herbicide-Resistant Canola LibertyLink® 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

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

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

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

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

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

Half-life of two sulfonylurea herbicides 12 d 40 d

Range of experimental half life of Pursuit

Herbicide Carryover When rotating to canola Herbicide families of primary concern (ALS Inhibitors – Group 2) Imidazolinones (IMI’s) Assert, Pursuit, Beyond Sulfonylurea (SU’s) Ally, Amber, Express, Glean, Harmony GT, Maverick, Osprey, Peak Sulfonylaminocarbonyltriazolinones Everest, Olympus

Canola plantback restrictions - IMI herbicides HerbicidePlantbackNotes Assert15 mo.Clearfield Canola may be planted the season following application Pursuit40 mo.MUST SUCCESSFULLY COMPLETE BIOASSAY Clearfield Canola may be planted the season following application Beyond/Raptor26 mo.Clearfield Canola may be planted anytime

Questions Joe Yenish 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 extension/