In western Canada, more money is spent on wild oat herbicides than on anyother weed species, and wild oat resistance to herbicides is the mostwidespread resistance issue. A direct-seeded field experiment was conductedfrom 2010 to 2014 at eight Canadian sites to determine crop life cycle, cropspecies, crop seeding rate, crop usage, and herbicide rate combinationeffects on wild oat management and canola yield. Combining 2× seeding ratesof early-cut barley silage with 2× seeding rates of winter cereals andexcluding wild oat herbicides for 3 of 5 yr (2011 to 2013) often led tosimilar wild oat density, aboveground wild oat biomass, wild oat seeddensity in the soil, and canola yield as a repeated canola–wheat rotationunder a full wild oat herbicide rate regime. Wild oat was similarly wellmanaged after 3 yr of perennial alfalfa without wild oat herbicides.Forgoing wild oat herbicides in only 2 of 5 yr from exclusively summerannual crop rotations resulted in higher wild oat density, biomass, and seedbanks. Management systems that effectively combine diverse and optimalcultural practices against weeds, and limit herbicide use, reduce selectionpressure for weed resistance to herbicides and prolong the utility ofthreatened herbicide tools.