I have a quick question about what I should do with a rhizhome that feel slightly soft to the touch. There aren't any easily visible holes from a borer or grub. While I've read about some remedies for mushy irises (Comet, lime, etc.) I'm not sure what I should do in my case, where the iris isn't obviously rotting yet.

It's been a strange spring with lots of cycles of wet cold weather followed by dry warmth.

Any thoughts?