White Mold (Timber Rot): Caused by Sclerotinia sclerotiorum, initial symptoms include whole plant wilting and chlorosis, followed by sudden plant death. Stem cankers may “shred” or crack, and plants lodge. White, fluffy mycelia colonize lesions under cool, wet conditions. Sclerotia are hard, black, and irregularly shaped. White mold is more prevalent in cool climates of the northern US and Canada. Sclerotinia sclerotiorum has a broad host range.
