Hay growers and livestock producers in Arkansas are used to dealing with fall armyworms, often as early as July. This year, a different version of the pest, the true armyworm, is already showing up in hayfields and pastures, says Kelly Loftin, entomologist with University of Arkansas Extension.
“We are seeing true armyworm damage in pastures across many areas of the state, but damage seems to be more concentrated in northeastern Arkansas with some pockets in the southwestern part of the state,” he says.
Typically, Loftin notes, true armyworms attack cool-season grasses and fescue. This year, though, producers in northeastern Arkansas have reported outbreaks in bermudagrass as well. “Within the last week or so, many acres of pasture have already been treated.”
For daytime scouting, producers will want to look carefully through the thatch at the plant base where the armyworms tend to hide. Generally, though, it’s better to scout for the pests at night when they’re most active, he says. As a rule of thumb, insecticide applications are warranted if three or more worms per square foot are present.
For more information on armyworm biology and control options, Loftin recommends Managing Armyworms in Pastures and Hayfields.