Adelges tsugae is a small, aphid-like insect that has become a serious pest of eastern hemlock and Carolina hemlock. The most obvious sign of infestation is the presence of white, woolly egg masses on the underside of hemlock needles. Infested eastern North American hemlocks defoliate prematurely and will eventually die if left untreated. A. tsugae is a difficult insect to control as the white waxy secretion protects it from pesticides. It is dispersed to new habitats through the nursery trade and locally by wind, birds, mammals and humans. Hemlock trees provide important habitats for many wildlife species and A. tsugae has severe adverse ecological impacts which will become more severe as its distribution expands.