Sooty mould is a fungal disease that often appears on plants, trees, and shrubs. This black, powdery substance can be unsightly and may potentially damage the health of the infected plant. There are several synonyms for sooty mould, including black mildew, smut, and black fungus. Other terms that may be used include saprophytic fungi, which refers to fungi that feed on dead organic matter, and honeydew fungus, which is named after the sticky substance that aphids and other plant pests produce, which can lead to the development of sooty mould. Effective treatment for sooty mould typically involves controlling the pest infestation that caused the fungal growth in the first place.