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Cottonycushion Scales 

Cottonycushion Scales 
Cottonycushion scales are a type of soft scale (see Soft Scales). Like other soft scales, they have a crusty skeleton on the outside of their bodies. However, it is rarely seen because the mature female scales lay hundreds of eggs in white, waxy egg sacs that are attached to their bodies, giving them a cottony appearance. The females die and shrivel after they lay their eggs. The young scales, called crawlers, emerge from the egg sacs and migrate to leaves and young twigs. They insert their mouthparts into the plant and suck sap throughout the summer. Trees and shrubs infested with cottonycushion scales may be coated with large quantities of a sticky substance called honeydew, undigested sap excreted by the insects. Male cottonycushion scales are tiny winged insects, which mature before females. They mate with immature females and die. Before the leaves drop, scales migrate to bark to spend the winter.
Cottonycushion scales may be difficult to control because they are protected by the waxy egg sacs. Control is often aimed at the crawler ' ' stage, whose time of appearance varies with the species. Spray crawlers on ornamentals with an insecticide containing acephate. Crawlers on fruit trees can be controlled with an insecticide containing carbaryl, malathion, or diazinon. Contact your local County Extension Agent (see County Extension Agents) to determine the best time to spray for scales in your area. A horticultural oil spray is very effective against the eggs and often against the crawlers.