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Camellia cushion scale (Chloropulvinaria floccifera)
Hosts
Camellia, Ilex (holly), Euonymus japonicus, Rhododendron, Trachelospermum, Taxus (yew) and some other evergreen plants.
Symptoms
A heavy coating of black sooty mould forms on the upper leaf surface; this develops over the winter months and persists into the summer. Yellowish-brown, oval scale insects up to 3mm long can be seen near the veins on the undersides of leaves; elongate white waxy egg masses are present in early summer.
Biology
There is one generation a year with eggs hatching in early-mid summer. The scales suck sap and excrete a sugary honeydew that coats the upper leaf surface, allowing sooty moulds to develop, especially during the winter.
Control
The newly hatched scales in late June-July are the most vulnerable stage in the life cycle. Systemic
insecticides containing imidacloprid + sunflower oil (Provado Ultimate Bug Killer concentrate), acetamiprid (Scotts Bug Clear Ultra) or thiacloprid (Provado Ultimate Bug Killer Ready To Use) are absorbed into the foliage and taken in by the young scales as they feed. Organic pesticides, based on plant oils or extracts (Growing Success Fruit & Veg Bug Killer, Vitax Organic 2 in 1 Pest and Disease Control, Scotts Bug Clear for Fruit & Veg ) or fatty acids (Bayer Organic Pest Control, Doff Greenfly and Blackfly Killer, Greenfingers Organic Pest Spray, Nature’s Answer Natural Fungus and Bug Killer), have no persistence and may require frequent use to deal with the scale nymphs as they hatch.