The potential for an unusual back-to-back armyworm infestation has Ontario farmers on the lookout. The Ontario Ministry of Agriculture and Food and Ministry of Rural Affairs say it’s “rare” to experience armyworm outbreaks two years in a row. Natural enemies (such as parasites and pathogens) build up in an outbreak year, and are in good supply the following year to keep up with the armyworm, according to provincial entomologist Tracey Baute. “However, armyworm outbreaks do tend to occur after a cool, wet April, (because) those conditions are detrimental to these natural enemies,” Baute says. “April was just that — cool and wet.” Baute urges farmers to scout for armyworm in forages and wheat now to stay ahead of any problems, particularly in fields with a history of infestations. Once they get to be an inch or larger, she says, it is difficult to control them. Cool, wet weather can impact the natural enemies of other pests too, she says. For example, cereal leaf beetle and alfalfa weevil are two pests that Baute says can “get out of hand” after a cool wet spring.