Severe Defoliation of American Elm by the invasive insect Elm Zigzag Sawfly (EZS)

by Owen Clarkin, OFNC Vice-President & Chair, Conservation Committee The Ottawa Field-Naturalists' Club has been tracking Elm Zigzag Sawfly (Aproceros leucopoda) since its recent (2020) detection in North America near Montreal.  This includes making the first observations of EZS in Ontario (2020), the city of Ottawa (2021), the state of Vermont (2022), and the city [...]