Woolly Aphid

Often found on the leaves, twigs, and bark of host trees such as apple, elm, hawthorn, and alder.

Herbivorous; they pierce plant tissues to suck out sap (phloem), often causing curling or yellowing of leaves.

They produce a white, waxy, cotton-like substance for protection against predators and desiccation. Some species are known as 'boogie woogie aphids' for their rhythmic swaying when disturbed.

Generally harmless to humans but can be a garden pest by weakening trees and producing honeydew, which leads to sooty mold growth.