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.
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Sumac (or /ˈs(j)uːmæk/; also spelled sumach) is any one of approximately 250 species of flowering plants in the genus Rhus and related genera, in the family Anacardiaceae. The dried berries of some species are ground to produce a tangy purple spice often used in juice.
Sumacs grow in subtropical and warm temperate regions throughout the world, especially in North America.
Sumacs are shrubs and small trees that can reach a height of 1-10 meters. The leaves are spirally arranged; they are usually pinnately compound, though some species have trifoliate or simple leaves. The flowers are in dense panicles or spikes 5-30 cm long, each flower very small, greenish, creamy white or red, with five petals. The fruits form dense clusters of reddish drupes called sumac bobs.
Sumacs propagate both by seed (spread by birds and other animals through their droppings), and by new sprouts from rhizomes, forming large clonal colonies.
Species including the fragrant sumac (Rhus aromatica), the littleleaf sumac (R. microphylla), the skunkbush sumac (R. trilobata), the smooth sumac and the staghorn sumac are grown for ornament, either as the wild types or as cultivars.
The leaves of certain sumacs yield tannin (mostly pyrogallol), a substance used in vegetable tanning. Leather tanned with sumac is flexible, light in weight, and light in color, even bordering on being white.
Dried sumac wood is fluorescent under long-wave UV light.
Mowing of sumac is not a good control measure as the wood is springy resulting in jagged, sharp pointed stumps when mowed. The plant will quickly recover with new growth after mowing. See Nebraska Extension Service publication G97-1319 for suggestions as to control.
At times Rhus has held over 250 species. Recent molecular phylogeny research suggests breaking Rhus sensu lata into Actinocheita, Baronia, Cotinus, Malosma, Searsia, Toxicodendron, and Rhus sensu stricta. If this is done, about 35 species would remain in Rhus. However, the data is not yet clear enough to settle the proper placement of all species into these genera.
Rhus sp. nov. A is a so-far unpublished species, endemic to Yemen. Its natural habitats are subtropical or tropical dry forests, subtropical or tropical dry shrubland, and rocky areas. It was given the status of "vulnerable" by the IUCN Red List.