Lawn Armyworm (Spodoptera maurita) are a major pest during summer and autumn, causing severe damage to turf grass surfaces where they attack leaves, stems and seed heads. Infestations in turf gradually extend outwards from gardens or higher cut turf areas as these plants are used as egg laying sites. Severe damage is predominantly caused by the later instar stages and as populations increase, the larger armyworms tend to move in groups into unaffected turf grass areas, hence the name ‘Armyworm’. Armyworms characteristically have stripes or triangular patterns along their smooth body, differing from that of the sod webworms, which can also cause damage, but usually less than Army Worms.
Armyworms are the larvae of moths of the family Noctuidae. The female moth may lay more than 1000 eggs, sporadically in clusters within 4 to 10 days, pending on temperature. The newly hatched armyworms stay together feeding on the same plant until it is devoured. The larvae are usually most active in the evening or at night, except in overcast weather conditions