Description:

• The adults have stout bodies and a wingspan of 40 mm.
• The forewings are reddish-brown with brown spots.
• The hindwings are grey with a black margin.
• The budworm caterpillar colour may vary form light green to almost black.
• They always have a distinctive broad white stripe on each side of the body.
• They have conspicious body hair.

Symptoms:

Native budworms occur in spring and summer. They cause economic damage to many crops including lucerne grown for seed. Caterpillars chew into and destroy flower buds and crop flowering may be delayed or retarded. Helcoverpa larvae also chew into pods and leaves. Damage can be substantial if left unchecked.

• Nabis, beetles, lacewings, wasps, spiders and birds are some of the natural enemies.
• Nucleopolyhedrose virus (NPV) is often an effective biologoc agent.
• Monitor field regularly, especially at budding stage for lucerne.
• Continue to look for sitona weevil.

Control:

Helicoverpa is most damaging to budding lucerne therefore it is critical to protect the plant at that time. Lucerne can however tolerate some damage (particularly when flowers are open) as only a percentage of flowers need to set pods to produce a good yield. Many natural factors can prevent Helicoverpa reaching a damaging level, so consider these before spraying.

CMS First In Integrated Pest Management Copyright © Crop Monitoring Services Pty. Ltd. All rights reserved.
Pest of December Web Page created by Raymond Christinat , last updated May 2006
Please kindly email the author of any error.