Mussel Scale (Lepidosaphes ulmi)
Armoured scale insect forming mussel-shaped covers on bark and twigs.
Mussel scale (Lepidosaphes ulmi) is an armoured scale insect found on fruit trees and ornamentals. It forms elongated, mussel-shaped covers on bark and twigs, weakening branches and predisposing trees to other stresses. Biological control includes parasitoid wasps and predatory beetles, supported by promoting natural enemies and targeting crawler stages where possible.
Biological Controls for Mussel Scale (Lepidosaphes ulmi)
The species below are examples of beneficial organisms commonly used against mussel scale (lepidosaphes ulmi). Recommendations are based on published biological control information and practical IPM experience. Always confirm suitability for your crop, growing system and local conditions before use.
Cryptolaemus montrouzieri
Environment: outdoor
Temperature Range: 16.0 – 28.0°C
Rate: 2–5 beetles per infested branch
Frequency: Repeat following season if required
Biocontrol contribution in fruit trees; combine with winter oils and pruning.
Further BioWiki Reading
For more background on pest biology, beneficial insects and environmental factors, use the BioWiki alongside this practical control guide.
Related Biological Solutions
Growers dealing with mussel scale (lepidosaphes ulmi) often also monitor these pests as part of a complete IPM programme: