sustainability through science & innovation

Vegetable beetles

Grower, Bronwyn Hunt (Merriwa Pastoral Company), has observed moderate-high numbers of adult vegetable beetles (Gonocephalum sp.) along firebreaks and fencelines of several paddocks near Kerang, in the Mallee district of Victoria. The presence of vegetable beetle adults in spring is not unusual and is generally not of concern. Vegetable beetles typically attack germinating crops in autumn.

Vegetable beetle larvae are minor pests of winter cereals, while the adults can attack emerging canola seedlings. The adults will also occasionally attack spring-sown crops, such as sunflowers. Typical damage includes chewing seedlings at or above ground level, ring barking plants or completely cutting stems.

In recent years there has been an increase in reports of vegetable beetles attacking crop plants in many regions of south-eastern Australia. It is unclear exactly what has triggered this increase. High populations are often associated with patches of previously high plant residues. Factors including temperatures > 20°C, moisture stressed crops, and light, dry soils have also been associated with cases where vegetable beetles have been found attacking crops.

Vegetable beetles (sometimes referred to as ‘false wireworms’) usually have one generation per year, with adults emerging in spring. Common species are 6 – 10 mm long, and have a dark grey-black coloured body, which is oval-shaped and often covered in soil. Larvae are elongated, hard-bodied, cream, yellow or tan in colour, with three pairs of legs just behind the head. The body is cylindrical and up to 20 mm long.

Click here for images of vegetable beetles.

PestFacts is supported by