Flea beetles are the most serious pest of canola in North Dakota, according to the NDSU Extension Service. Fields should be checked daily for the presence of flea beetles while canola plants are at risk. The weakness of foliar control strategies is often the inability to cover large numbers of acres quickly when feeding pressure is high, and residual protection by the insecticides is short, allowing for reinfestation to occur. Wet fields can result in more wet-weather weeds, such as nightshade and biennial wormwood, and heavier infestations of common weeds such as pigweed, kochia, wild buckwheat, foxtail, and wild oats. Watch out for shifting spectrums in fields flooded this spring, says Richard Zollinger, NDSU Extension weed specialist.
Water can carry weed seed from field to field.
Expect to see some weeds that weren't in your fields last year. Typically, we get one or two major weed flushes, then it turns hot. But with continued wet conditions, we could see even more weed outbreaks. Controlling weed outbreaks requires close field monitoring. You can't just check once and assume those are the only weeds you've got to take care of.