Diagnosing European earwig
A chewing insect introduced from Europe that can damage seedling crops and contaminate grain. Mainly found in the southern wheatbelt.
What to look for
- Seedling stumps or shredded leaves, usually in patches and areas with higher stubble or pasture residues.
- At times, European earwigs are a nuisance around buildings and can spread into adjacent crops.
Paddock
- Leaves are irregularly chewed leaving petioles and wispy dead leaf veins.
Plant
- Shiny flattened insects with a dark brown body and light brown/yellow legs and pincers. Juveniles are smaller and paler.
- Earwigs are nocturnal but can be found hiding under rocks and plant material during the day.
Insect Adult
What else could it be
Condition | Similarities | Differences |
---|---|---|
Diagnosing vegetable beetle damage | Chewed plants, seedling death | European earwigs chew the leaf blade and tend to leave stems, petioles and veins, and are usually found near affected plants |
Diagnosing cutworm in cereals | Chewed plants, seedling death | European earwigs chew the leaf blade and tend to leave stems, petioles and veins, and are usually found near affected plants |
Diagnosing weevils in canola | Chewed plants, seedling death | European earwigs chew the leaf blade and tend to leave stems, petioles and veins, and are usually found near affected plants |
Diagnosing slugs in crops | Similar plant damage with shredded leaves | European earwigs are usually found near damaged plants, and are not restricted to heavy soil types like slugs |
Native earwigs
|
Similar appearance | Native earwigs are not found in high numbers and do not congregate together |
Where did it come from?
- The European earwig is native to Europe, and was first found in Western Australia in 1990. It is well established in towns, but distribution is patchy in the agricultural area.
- Adults have wings but they seldom fly and are mainly spread by human activity. They are easily transported in machinery and vehicles, containers and plant material.
- They usually breed once a year. The length of the lifecycle depends on temperature. At 25°C, the development from egg to adult takes nine to ten weeks, but at 15°C it takes up to five weeks longer.
- European earwigs feed on a wide range of food types such as organic matter, fruits, ornamental plants, vegetables, flowers, seeds and live and dead insects, including earwigs and caterpillars.
Management strategies
Stubble management
Spraying insecticide
- Currently there are no broad-acre insecticides registered for use in broadacre crops.
- Grain contamination when harvesting swathes can be minimised by harvesting during the day.
- Reducing retained stubble decreases populations of this pest.
- Insecticides registered for use around the exterior of buildings and structures will reduce spread into adjacent crops.
Where to go for expert help
Page last updated: Monday, 1 May 2017 - 11:54am