The species Eriosoma lanigerum corresponds to the Woolly Apple Aphid that infests such plants as apple, hawthorn, elm and pear. The wooly apple aphid has a distinctive, white-waxy covering, which usually conceals the body shape of the insect. The aphid colonies resemble small tufts of wool or cotton batting. Damage caused by this species of pest is the result of feeding on new terminal leaves, causing them to curl up with physiological stress to the plant. In cases of heavy infestation, twigs and branches may become deformed, resulting in heavy stress on the trees and affecting productivity.
Woolly Apple Aphids differ in appearance from apple mealy bugs, by their reddish-coloured bodies that are covered by a wool-like waxy material. The species E. lanigerum presents mobile stages, known as “crawlers” (although different from those of scales), which are very small, brown and have tufts of white wax at the hind end. At maturity, the insect can reach up to 2 mm in length and are reddish-purple, but usually covered completely by a white waxy material.
When scouting, inspect twigs, branches, wounds and splits in the bark, as well roots of the host, for white waxy material. Try to control the pest when the initial infestations are detected. Higher populations can be difficult to control. Therefore, combinations of contact and systemic insecticides may be required for the efficient management of this pest.