Scale insects

Adult scale insects are usually covered in waxy shell-like cover. There are more than 25 species of scale insect found in British Gardens. Each species has a different host range and life cycle. They feed by sucking sap and some can weaken host plants, many excrete a sticky substance (honeydew), which allows the growth of sooty moulds.

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Scale insects on bay. Image: RHS, Horticultural Science

Quick facts

Common name: Scale insects
Scientific name: Various species
Plants affected: Many greenhouse and garden fruits and ornamental plants
Main symptom: Scales on stems and leaves, sooty moulds on foliage
Most active: Year round

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