Other regional agencies will be initiating a trapping program for this species and other armyworms. The presence of moths reported here are considered ‘non-target by-catch’ = the large yellow underwing moths (Noctua pronuba) were caught in pheromone traps deployed for other species in another program (OSU VegNet). Nevertheless, it has proven to be at least an indicator of timing over the past few years.
N. pronuba moths are easily recognized by their large size (2-3″ wingspan) and bright yellow-orange hindwing bordered by a thick black margin (FIG. 1). Review similar posts for more information about this species. Larvae behave as armyworms and can be active throughout the fall and winter.