Description

• The adults are brown and have a distinguishing yellow X-shaped cross. Juveniles do not have a cross — they have two small spots on their back.
• Approximately 2.5 cm long.
• Three to four generations per year.
• Five nymphal stages.
• Eggs are large, elongated and brown, with a rounded lid.

Damage

• Crusader bugs feed on young plant growth, resulting in the wilting of shoots. The shoots go brown and often die back to the old wood.
• All citrus varieties can be attacked.

Monitoring

• Monitor once or twice during October–April by checking five randomly selected shoots on each tree.

Natural enemies

• Assassin bugs
• Praying mantises
• Birds
• Parasitic wasps

Control measures

• If 25 or more of the shoots are infested, spot spray with a selective insecticide.

More information

• Naturebase Plants and Animals of Australia (science.calm.wa.gov.au)