Dirt-like sclerotia results in little or no damage to tuber - Claflin, Larry (My University, 1977)
These sclerotia are commonly known in the trade as, "the dirt that won’t wash off". Other than being unsightly, the result in little or no damage to the tuber.
Host/Plant: Potato (Solanum tuberosum subsp. tuberosum)
Pest/Path: Rhizoctonia Canker and Black Scurf (Rhizoctonia solani)
Keywords: Fungal Diseases; Potato Diseases; Rhizoctonia; Color photographs