
Cottony-cushion scales (Icerya purchasi, magnified)
Scale insect (
Icerya purchasi, order Homoptera) that is a pest especially of California
citrus trees. The adult lays bright red eggs in a distinctive large white mass that juts out from a twig. Distributed worldwide, cottony-cushion scale is found on many other plants, including acacia, pittosporum, and willow. Australian ladybird beetles (
see ladybug), a natural enemy, have been imported to keep it from destroying the California citrus industry.
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Encyclopedia Britannica, 2008. Encyclopedia Britannica Online.