Honeysuckle aphid is one of the most damaging insect pests of bush-type honeysuckles. It was first recorded in Illinois in 1981 and occurs heaviest in the northern half of the state, although it can be found as far south as Effingham. Aphids cause plant injury by injecting toxins or growth-regulator–type substances with their saliva when feeding. These substances stunt new growth and cause twigs to branch into clusters called witches’-broom. Affected branches can die in winter, and heavy aphid infestations can kill plants.
Honeysuckle aphids overwinter as eggs, laid in the fall on the tips of branches. They hatch in the spring into wingless females when leaves are expanding. Aphids that develop from eggs can give birth to live young. The aphids start feeding when leaves are fully expanded. Honeysuckle aphids are cream colored and feed on new shoots on leaf undersides and in folded leaves. There are multiple generations during the summer, and winged males and females can be found in early fall.
Management of honeysuckle aphid includes the use of resistant varieties of honeysuckle, proper cultural practices, and the use of insecticides. Honeysuckle varieties that are resistant to honeysuckle aphid are Arnold’s Red, Clavey’s Dwarf, and Emerald Mound. Proper watering and fertilization practices can also lead to fewer problems with this pest. Avoid overwatering and overfertilizing plants, especially with nitrogen, as these practices prolong infestations by stimulating succulent shoot growth. Prune out witches’-broom growth before buds break to remove overwintering eggs.
Systemic insecticides used to manage honeysuckle aphid include acephate (Orthene), imidacloprid (Merit), and oxydemeton-methyl (Metasystox-R). These products help to obtain control within the folded leaves. Make repeat applications when needed. Orthene and Metasystox-R should give a month of control, whereas Merit may give season-long control. The benefit of using systemics is the long lasting residual activity and preservation of natural enemies. Be sure to read the label for instructions on the application methods for these systemics.