Answer: It's difficult to absolutely diagnose a problem without actually seeing it, but your description sounds more like injury to the tissues of the canes rather than symptoms of a disease. If the outer layer of tissues are bruised or scraped, they can flake off as you've described. I'd suggest waiting and watching your rose to see if the problem areas get larger or spread to unaffected areas of the cane. If the problem gets worse, cut one of the canes off and take it to your Cooperative Extension office for diagnosis. You'll find an extension agent or Master Gardeners at: University of California Cooperative Extension, 2604 Ventura Ave. Rm 100, Santa Rosa, CA 95403. Phone (707) 527-2621.
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