Canola is sensitive to carryover from many herbicides. View Table 1. Recropping restrictions for residual herbicides in the Canola Encyclopedia for a list of products that could be used this fall on fields planned for canola next spring, and refer to product page of your provincial crop protection guide (ex. Alberta Crop protection Guide (The Blue Book), Saskatchewan Guide to Crop Protection, Manitoba Guide to Field Crop Protection, Ontario Crop Protection Hub) for more information.
Remember to read all notes carefully. Some cannot be applied after a certain date. You’ll find useful pointers to help in your product choice and herbicide timing.
|wdt_ID||Herbicides registered for use in the fall on land planned for canola.||Notes and recommendations|
|1||Glyphosate||Apply at least 1,040 GAE (grams of glyphosate acid) per acre to get effective perennial control, given that leaf area will be smaller than pre-harvest. Monsanto does not recommend any tank-mixes with Roundup for use in fall.|
|16||Distinct||Distinct combines Group 4 dicamba and Group 19 diflufenzapyr. BASF recommends it as a tank mix partner with glyphosate for enhanced control of broadleaf weeds. Apply prior to October 1 at 58 g/acre when planning a canola crop the following year.|
|3||Tribenuron (Express SG, Spike, Nuance, MPowerX)||DuPont recommends an application of its Express SG before October 1 on fields planned for canola. Express SG must be tank mixed with at least 0.5 litre/acre glyphosate equivalent for fall application prior to seeding canola in spring.|
|4||Heat LQ||Heat LQ (Group 14 saflufenacil) can be applied in fall to prep land for canola the following spring. Applications can be made any time during the fall on actively growing weeds.|
|19||2,4-D||Use caution. Phenoxies (2,4-D, MCPA) should not be used in the fall on fields planned for canola next spring. The most effective timing is just prior to freeze-up, which does not allow enough breakdown until after the soils warm up in spring.|
|6||MCPA||MCPA has no recropping restrictions listed, but it does present a re-cropping risk for canola – especially when conditions at application are extremely dry. Growers are advised to avoid using MCPA on land intended for canola next spring.|
|7||KoAct||KoAct has both 5 oz of 2,4-D and 4 g of tribenuron. NuFarm is comfortable with an October 15 cutoff with this product.|
|8||Lontrel||You need higher rates and generally get poorer control in the fall than the early in-crop stage.|
|9||Soil-active herbicides approved for fall application on fields planned for canola||These products are applied in the fall but are designed to control weeds emerging early in the spring. The act of incorporation will provide some management of existing fall weeds. Notes and restrictions:|
|10||Avadex (triallate)||It controls wild oats and wild millet as they emergence through the herbicide layer in the spring. Fall activity is not really needed or desired for these annual weeds anyway.|
|11||Bonanza, Rival, Treflan (trifluralin)||Trifluralin becomes active at soil temperatures typically above 5°C, so apply it in the fall at cooler temperatures before soil freeze up so it doesn’t dissipate before the spring.|
|12||Edge (ethalfluralin)||This Group-3 herbicide goes on dry and must be worked to a depth of 1/4" to 1/2" into the soil. Light harrow is often enough. Apply after September 1 for conventional till, after October 1 for no-till/min-till.|
|13||Fortress (triallate, trifluralin)||This is applied in the fall but stays dormant all winter. It controls wild oats and wild millet as they emerge through the herbicide layer in the spring. Fall activity is not really needed or desired for these annual weeds.|