Hemlock Woolly Adelgid

When looking for eastern hemlocks, keep your eyes peeled for egg sacs of the invasive Hemlock Woolly Adelgid (Adelges tsugae). They appear in fuzzy, snow-white clusters on the branches of hemlocks, right at the base of the needles. The adult insects themselves are tiny, but negatively impact the health of entire forest systems across the eastern United States. Native to East Asia, they use their sucking mouthparts to feed on the sap of hemlock trees, eventually killing or leaving their host weakened and susceptible to disease. Biological control methods are still being developed by forestry services, but there are chemical treatments available for short-term management.

Photo by Laura Berry.