Citrus mealybugs (Planococous citri) are normally under good biological control by a complex of natural enemies in citrus. Their waxy covering, sedentary lifestyle, and preference for feeding in concealed locations make them very difficult to kill with insecticides. Only the most toxic materials have appreciable efficacy against mealybugs, materials that also pose risks to the environment and are most likely to disrupt biological control of other pests. Consequently, treatment is warranted only in cases of severe infestations, or when the fruit itself is attacked. Systemic materials give superior control while minimizing impacts on beneficials, but may not act quickly enough to prevent damage when high populations are established.