Hi Joan,

A number of bugs use this plant for food, it's all part of the cycle of nature. Most of the leaf damage occurs in late springtime. Your Joe Pye weed is vigorous enough that it will outgrow the damage, so no action is necessary.

From a Minnesota website:

"As a rich source of nectar, Joe Pye Weed plants are used by a wide range of
pollinators including honey bees, bumble bees (including the threatened Rusty
Patched Bumble Bee), Cuckoo bees, digger bees, leaf-cutter bees, bee flies,
butterflies, and moths. The species is used by monarch, azure, skipper, white
admiral and swallowtail butterflies. A variety of beetles, aphids and caterpillars
also use the species as a food source. It is also a larval host plant for the Three-
lined Flower Moth and the Ruby Tiger Moth."

I see this damage on my own Joe Pye weed every year and it never holds the plant back. Be glad you have a plant in your yard that is supporting important insects and pollinators!

Here's a link to the website I drew the above information from:

https://bwsr.state.mn.us/sites/default/files/2018-12/March%202015%20Featured%20Plant%20Joe%20Pye%20Weed.pdf

I hope this helps. Good luck!