Woolly apple aphid
Eriosoma lanigerum (Hausmann)
Hemiptera: Sternorrhyncha: Aphididae
The colonies of reddish brown adults (A) and nymphs (B) produce waxy secretions, which resemble small tufts of wool or cotton batting (C). The aphids are without cornicles, possessing only abdominal pores.
Widespread and a major pest in most fruit-growing states and provinces in eastern North America.
Attacks apple and pear. The woolly apple aphid causes the formation of nodules on the woody parts of trees and roots (D). The nodules can split and develop into cankers. This aphid excretes honeydew on leaves and fruit that favors the growth of sooty mold.
Use of resistant apple rootstocks recommended. Protect natural parasitoids. Check for colonies on pruning scars and on interior and upper branches, beginning in early to midsummer; if necessary, apply selective insecticides (aphicides) when they appear.
The MSU IPM Program maintains this site as an access point to pest management information at MSU. The IPM Program is administered within the Department of Entomology, fueled by research from the AgBioResearch, delivered to citizens through MSU Extension, and proud to be a part of Project GREEEN.