Joe-Pye Weed leaves have holes all over

Asked June 11, 2020, 3:15 PM EDT

Something is attacking my Joe-Pye Weed plants. Small holes started appearing in the leaves over a week ago, and it’s getting worse. I’ve tried snipping the affected leaves off, but there are too many plants to do this to all of them. There is no discoloration around the holes and haven’t seen any bugs. What do you think is going on? How can I stop this? Would you let me know. Thank you.

Hennepin County Minnesota

2 Responses

Joe pye weed attracts many insects that eat leaves. I'm not sure what the insect is that is doing this damage. Possibilities include slugs and leaf cutter bees. I see plenty of photosynthetic material in your photo so the damage is not harming the plant. Cutting off the leaves that have damage is not going to stop the insect but will remove photosynthetic material that the plant uses to regenerate, so please don't do that.

Here are references on leaf cutter bees:

And on slugs:

Thank you.