Methods for controlling the growth of trifluralin-resistant annual ryegrass in cereals using dithiopyr are described. The methods include contacting the locus of the cereal, at planting or before weed emergence, with an herbicidally effective amount of dithiopyr. The dithiopyr can be applied to the soil and either incorporated into the soil at the time of planting the cereal or applied post-planting to the soil surface before the weeds have emerged.