Hemlock Woolly Adelgid – Adelges tsugae (Annand)

Damage - Adelges tsugae (Annand), Hemlock Woolly Adelgid

Hemlock woolly adelgid is an aphid-like insect that attacks and kills hemlock trees. Its egg sacs, which look like cotton balls or clumps of snow, can be found at the base of needles. It can be spread by wind, animals, and human movement of nursery stock, logs, and other wood products including firewood.

Hemlock woolly adelgid was first reported in Canada in British Columbia in the 1920s and in the United States (Virginia) in the 1950s. It was also detected and eradicated in Ontario in 2011 and 2013, and has been establishing itself along the eastern coast of the United States. In 2017 it was detected in Southwestern Nova Scotia and the CFIA continues to survey for the pest to determine the extent of its spread.

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