Any of several fungal diseases of plants causing black, scurf-like discoloration; especially a disease of potatoes caused by Rhizoctonia solani in which small fungal growths appear on the skin of tubers.
Origin
Late 19th century.
Definition of black scurf in US English:
black scurf
noun
Any of several fungal diseases of plants causing black, scurf-like discoloration; especially a disease of potatoes caused by Rhizoctonia solani in which small fungal growths appear on the skin of tubers.