Q: My small ‘Whitespire’ Japanese birch has been defoliated each fall for about the past three years. No permanent harm because it comes right back every spring. I just found these hungry little guys on it and wonder if they are butterflies or moths to be because of their close proximity to my butterfly bushes.
A: They are the larvae of neither butterfly nor moth. They are the children of the dusky birch sawfly, a wasp-like insect.
Since they are not caterpillars, products containing Bacillus thuringiensis won’t kill them. Spray the trees with any garden insecticide instead.
Tags For This Article: insects