This habit of congregating soon kills the infested leaves and causes a forced migration of aphids to new feeding sites. The young move actively and hurriedly, seemingly anxious to locate a suitable feeding site. They are frequently found during this period attacking the new, succulent unfolding foliage. Aphids are on the apples in May and decline through June and July. In recent years, greater numbers appear to be staying on apple trees and reproduce in large numbers until later in the summer.
Treatment is recommended, if an average of one or more colonies per tree is found.
Apply foliage applications of systemic or contact insecticides early in the season. Early applications, when the aphids are fully exposed and before they curl the leaves, are most effective. Systemic pesticides are required once leaf curling has occurred. Systemic insecticides will control the spread of this aphid in the tree and also protect against other leaf feeding pests. The table on this page indicates the dates and sites of the 1998 training seminars to certify apple pest scouts to conduct the trapping program required by the Brazilian government for exporting apples to Brazil.