Brown pasture loopers

Brown pasture loopers, an occasional pest of pastures and crops, have been identified in several lucerne pasture crops, and unusually appear to be preferring lucerne over capeweed

 

Where have they been reported?

Brown pasture loopers (Ciampa arietaria) have been identified in several lucerne pasture crops near Bridgewater and Maryborough, in Victoria’s North Central region. Densities of around 16 larvae per metre were found damaging shoot growth in the lucerne crown. Although the paddocks had a significant capeweed population, the grubs appeared to be preferentially feeding on lucerne and ignoring the capeweed.

Brown pasture looper habits and behaviour

Brown pasture loopers are an occasional pest of crops and pastures in southern regions of NSW and Victoria. They attack lucerne, pastures and broadleaved weeds and crops, particularly canola and lupins. They have one generation per year and are generally present from July to October. They are most damaging when large sized caterpillars (>20 mm in length) transfer from autumn/winter weeds onto seedlings or young plants. Plant leaves are chewed from the edges, and the caterpillars are often easily located feeding during the day. Moths fly from March to June and eggs are laid at this time.

Our advice

Brown pasture loopers are generally common around patches of weeds, particularly capeweed, and around the edges of crops (moving in from neighbouring weedy margins). These areas should be monitored closely and spot or perimeter spraying is often all that is required. Avoid unnecessary chemical applications that are harmful to beneficial insects. Brown pasture looper eggs can be attacked by wasp caterpillar parasitoids. Spined predatory shield bugs, carabid ground beetles and glossy shield bugs attack young larvae.

Description

Brown pasture looper larvae are dark brown to grey in colour with a series of distinctively yellow triangles along the back either side of a conspicuous dark band. They have red spots surrounding the breathing holes (spiracles) on the sides of the body, and can grow to 20–35 mm in length. They move using a series of back arches, which results in a characteristic looping motion. Adult moths are pale dusty brown in colour with grey and brown streaks on the forewings.

 

*Source of field reports of brown pasture loopers

Guy Debnam – Agronomist, Landmark (Victorian Northern Country)