Any of certain species of shrubs and small trees in the genus Rhus of the family Anacardiaceae (the sumac, or cashew, family), native to temperate and subtropical zones.
All sumacs have a milky or resinous sap, which in some species (e.g., poison sumac ) can irritate the skin. Used in the past as a source of dyes, medicines, and beverages, sumacs are now valued as ornamentals, soil binders, and cover plants. The sumacs grown for landscape use display a graceful form, spectacular fall colour, or colourful fruit clusters. The smooth, or scarlet, sumac ( R. glabra ), native to the eastern and central U.S., is the most common.