A serious pest of grape vines, and often confused with the closely related Grape Mealybug. It also infests pear and apple trees, and with the potential to vector certain plant pathogens can be damaging to the plants. It has caused substantial damage to vineyards in California. Like most mealybugs the male and female are dramatically different, the male having wings and looking more like a fly, while the female is wingless, flattened, covered with white wax and remaining mobile but on the plants. Males do not feed and die immediately after mating, while females may live for several months. Egg laying may go on throughout the year, with females depositing clutches of several hundred eggs enclosed in cottony sacs. Eggs are laid in crevices and under the bark of the trees or vines, hatching in about 1 week in warm temperatures. Development to the adult female stage takes 6 to 9 weeks.
The use of dormant oils in the winter, applied thoroughly to the bark to contact eggs, may help to reduce the numbers that become active in the spring. Contact insecticides can be effective, particularly is combined with a wetting agent that helps penetration through the waxy covering of the mealybug.