Rhubarb mystery

Asked May 8, 2020, 4:10 PM EDT

At first, some stalks looked like they got stepped on. Cracked and brittle. Next I noticed some stalks looked stripped, or possibly slugs had a party, and ate the skin the length of the stalks, but barely any holes in any of the leaves. Also all these stalks were shorter than usual. Next I noticed discoloration of young, emerging leaves. Kind of a rusty color. I hope you can see on the pictures what I described

Pine County Minnesota

1 Response

It is impossible to diagnose diseases on the basis of photographs only. Many diseases look alike and mimic abiotic disorders. Often only a lab test can determine what pathogens are present.

In your case, if you've ruled out abiotic problems (watering, herbicide drift, recent nearby construction, perhaps this is bacterial soft rot. Read here:
https://pnwhandbooks.org/plantdisease/host-disease/rhubarb-rheum-rhabarbarum-red-leaf

Unfortunately, the only treatment is to rogue out the plants. To verify the diagnosis, here is how to send in a sample to the plant disease clinic:
https://pdc.umn.edu/submit-sample