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Azalea Bark Scale


Azalea Bark Scale

Usually appear in

Spring and Summer

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Caused By:-     The Scale insect Acanthococcus azaleae


Azalea Bark Scale Acanthococcus azaleae (Eriococcus azaleae) which belongs to the family Eriococcidae prefers azalea or rhododendron but can infest hawthorn, andromeda, maple, willow, poplar, willow and ornamental cherry trees and other plants. Females are approximately 1/8-inch long with white felt-like sacs that are secreted in April/May which enclose the body and where the eggs are laid in the spring and hatch from June to July. They overwinters as immature nymphs in the forks of the twigs. They suck the sap from the tree and weaken it. Infested plants usually appear chlorotic with weak growth. the plants are often covered with sooty mould which is a black fungus that grows on the honeydew excreted by the scales as they feed. Some twigs may eventually twigs may die back. Picture by United States National Collection of Scale Insects Photographs Archive, USDA Agricultural Research Service,
See these other Scale insects Azalea Cottony, Beech Bark, Brown, Eucalyptus Gumtree, Euonymus Mussel, Hemispherical, Horse Chestnut, Hydrangea, Juniper, Mussel, Oleander, San Jose, Scale, Soft, Viburnum Cushion, Wisteria, Wooly Vine.


There are biological predators that can be used to control this pest, but the best control is to spray in the winter with a winter oil wash which will kill the overwintering nymphs.

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