Key Points:
- Identify cosmopolitan armyworm by the smooth green-brown skin with a thin whitish line down the back and dark lines on each side. Differentiate it from the rough and spiked skin of corn earworm (Heliothis).
- Control of grass weeds will reduce the risk of outbreak populations.
- Cultivation may lower in fi eld populations of pupae and larvae (caterpillars) but moths can fly in from other grass habitats.
- Scouting crops is important for several weeks after silking.
- The army worm parasitoid wasp, Cortesia rufi crus, can give 70 - 95% mortality which is generally suffi cient control for maize crops.
- Registered insecticides are available should parasitism be insufficient.