Wood rot in which the fungus degrades the cellulose but not the lignin, leaving a brown, often cubical, firm residue; not as common as white rot.
Wood decay that is triggered by fungi that destroys cellulose in trees results in the decomposition of wood, leaving behind a residue of brown lignin. This is distinct from white rot. Additionally, the term is also utilized to describe diseases affecting fruits such as apples and pears, caused by the Monilinia (Sclerotinia) fructigena fungus.