Weed considerations for early May

Preseed burn-off or seeding? For best results, spray winter annuals when they’re small. They’ll be growing fast this week. Seed first or spray weeds? A situation

Seed then bet on post-seeding/pre-emergence application? If choosing to seed before spraying, weeds present will have a minimum five days — usually more — before the crop emerges. These weeds can advance very quickly in good conditions, which is why growers who seed before spraying may choose to apply in the narrow post-seeding pre-emergence window.

Herbicide carryover risk. This can be a factor if conditions were dry last summer and not conducive to normal rates of residual herbicide breakdown. This presents a risk to canola seeded in these fields. Keep this in mind if making last minute changes, swapping in canola where a group-2 tolerant crop was originally planned.

Further reading:

Seeding is two weeks away. Should I spray now?
Canola Watch library of pre-seed burnoff articles
Tank mix options for pre-seed burnoff
Individual product pages in the Guide to Crop Protection include details on tank mix compatibility as well as correct order of mixing compatible products. Alberta guide. Saskatchewan guide. Manitoba guide.
See pages 77-78 of the Saskatchewan Guide to Crop Protection for recropping restrictions for residual herbicides. This includes details on extended re-cropping restrictions for extremely dry conditions, if or when they exist. Contact the product manufacturer if you are unsure.