6 things to know about white mold
By Anne Dorrance, Ohio State University
This disease is caused by the fungus, Sclerotinia sclerotiorum and it is favored by cool damp conditions. Remember those morning fogs this summer and the fact that you hardly used your air conditioner? Perfect conditions for infection. This fungus forms hard black irregular shaped bodies called sclerotia. (photo of sclerotia inside stem) They are actually a mass of hyphae and if you break them open they will be pink inside. They can be mistaken for mice or rat droppings as well, the inside is a different color! When the conditions are cool and the canopy is closed, this fungus produces a very small mushroom (photo). This usually occurs during flowering and the spores then land on the dead flowers. This provides a perfect point of entry. This fungus produces oxalic acid – which degrades the tissue as it colonizes the plant. The infections that you see now occurred 2 to 4 weeks ago. Symptoms from the road will look like standing plants with a gray-green appearance. Eventually these plants will lodge. Once the leaves fall off – the plants will stand back up to some extent.