Description of adult
Adult females are dome shaped, dark brown to black in colour, and about 2mm across.
Tiny eggs are laid under the female. These eggs hatch into tiny, six-legged, cream coloured 'crawlers', mostly in summer.
After hatching the crawlers move up the stems and usually settle along the veins of young leaves. The crawlers moult after about 4 weeks and then migrate to the young stems and twigs. Here they will mature, developing protective brown shells, and lay eggs.
Olives, citrus and gardenia.
Feeding damage is usually minimal however sooty mould commonly develops on the honeydew excretions from the scale, disrupting photosynthesis.
The predatory ladybeetle, Cryptolaemus montrouzieri, can be purchased and released in spring-summer. It is often naturally present in orchards but is susceptible to toxic insecticides. Ants often 'farm' the honeydew and can keep the natural scale predators away.
'Crawlers' do not have the impervious shell of the adult and can usually be killed with 1 or 2 applications of white oil about 2 weeks apart.
Chemical registrations and permits
Check the Australian Pesticides and Veterinary Medicines Authority database for chemicals registered or approved under permit to treat this pest on the target crop in your location. Always read the label and observe withholding periods.
- Last reviewed: 19 Oct 2022
- Last updated: 19 Oct 2022