sustainability through science & innovation

Has pasture day moth caught your attention?

Although considered a sporadic pest, the sunset colours of pasture day moth are hard to miss…

Where have they been reported?

In the Barham area of the NSW Riverina, pasture day moth caterpillars (Apina calisto) have been reported in pastures (50/m2) and in volunteer peas within a wheat crop. Further west in the Victorian Mallee, these caterpillars have been found predominately feeding on capeweed within an oat crop, and on barley grass. They have also been observed in large numbers in a pasture paddock south-west of Kerang. For the second time season we have had reports of this pest damaging crops in the Kaniva region of the Victorian Wimmera. This time the damage was reported in lucerne. Lower numbers of pasture day moth caterpillars have also been observed around Horsham in several cereal crops.

About pasture day moth

Pasture day moth larvae are visually striking, especially when fully grown. They are dark brown with reddish-orange and yellow markings, and two distinctive yellow spots near the posterior end of the body. They are also noticeably hairy with prominent bristles and grow to approximately 60 mm in length. 

Pasture day moth caterpillar (Source: cesar).

 

Pasture day moth caterpillars most commonly attack broad-leaf weeds in pasture, such as erodium and capeweed. They occasionally damage cereal and pasture crops, canola, peas, sub-clover and phalaris grass. This typically occurs in paddocks where pasture day moth are present and broad-leaf weeds are dead or dying from a herbicide spray; the caterpillars will transfer off the dying host plants and onto nearby crop plants.

Pasture day moth passes through one generation per year. Eggs are laid in pasture and hatch with the autumn rains. Larvae feed during winter and spring. When they are fully grown, they may be seen burrowing into the soil, excavating a vertical tunnel where they pupate in a cell at the bottom.

Our advice

The benefit of controlling pasture day moth is questionable in most years. The last substantial outbreak was in 2007 where pasture day moth were reported across much of southern NSW, mostly attacking cereals and emerging pastures.

 

Sources of field reports of pasture day moth

Bronwyn Hunt – Grower (Victorian Mallee)

Simon Mock – Consultant, Clovercrest Consulting (Victorian Wimmera)

Kate Wilson – Agronomy Consultant, AGRIvision Consultants (Victorian Mallee)

Twitter sources

Scott Burger (@scottburger00)

Laura Kaylock (@LauraKaylock)

PestFacts is supported by