The eggs may take 6-20 days to hatch, depending on local temperatures. In spring, the common armyworm will also lay in the crevices between the ligules of lower senescing leaves and stem. 2012Īrmyworm eggs are laid in batches of about 5-30, glued together in the hidden, twisted crevices of standing dried grasses, straw and stubble or sometimes in seed heads. 2012 Distinguishing characteristics/description of armyworms. Photo by Cesar Australia Distinguishing characteristics/description of armyworms. All armyworms lay eggs in dry grass and stubble from previous cereal crops or pasture. They can also be found damaging crops during spring in cooler regions. Southern and inland armyworms, which are also migratory, are most commonly found in autumn and winter, often in relatively high densities. The common armyworm migrates into south-eastern Australian cropping areas in late winter or early spring laying eggs in cereals, rice and pastures. Larvae live and pupate in the soil and are generally nocturnal.Īdult moths are grey-brown in colour and have a stout body with a wingspan of approximately 40-45 mm. They have one pair of anal prolegs and four pairs of abdominal prolegs. The body stripes can vary, but the collar stripes are always present. Body colour can vary, but larvae are generally green, brown or yellow with three parallel white longitudinal stripes running from the ‘collar’ behind the head, along the body to the tail end. They are difficult to distinguish apart, however, correct species identification in the field is generally not critical because their habits, type of damage and control are similar.Īrmyworm caterpillars of all species are about 1mm long after hatching and grow up to 40 mm in length and usually have smooth bodies with a few fine hairs. Note that the common armyworm, Leucania convecta, was formally known as Mythimna convecta.

The three armyworm species commonly found in southern Australia are the common, southern and inland armyworms.

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