
Hemlock woolly adelgid (HWA) infestation on underside of eastern hemlock branch in Connecticut. This tiny sapsucking insect from Asia, discovered in Virginia in 1951, is a major killer of eastern hemlocks, which are vitally important to Northeastern forest ecosystems. HWA is named for its woolly egg masses. Thanks to introduction of the Japanese ladybeetle, a predator of HWA, many hemlocks in Connecticut have survived since the first waves of tree mortality some 35 years ago.