Iris Root Borer?
A friend who was helping me weed discovered evidence of what she said was an iris root borer. Can you tell from these photos if that is what I have? Other than digging up the rhizomes and removing the infected parts, then replanting, is there anything I can do at this time of year? She remembered putting the rhizomes in a bag of something dry (a specific substance) for a few days, then replanting, mixing into the soil a little of the substance, but the articles I'm reading don't talk about that.
Hennepin County Minnesota
I don't know what your friend was talking about but digging them up. Removing the infected parts and then replanting is the cure. Also, iris should be cut back in the fall and all old leaves removed. https://extension.umn.edu/yard-and-garden-insects/iris-borers