Sumac

Sumac (also spelled sumach) refers to about 35 species of flowering plants in the genus *Rhus* and related genera, part of the cashew and mango family, Anacardiaceae. It should not be confused with poison sumac. The plants are found in subtropical and temperate regions across nearly every continent except Antarctica and South America. The species most commonly used in cooking is *Rhus coriaria*. Sumac is valued as a spice, particularly in Middle Eastern cuisine, and also serves as a dye and a traditional remedy. It holds cultural importance as a symbolic item on the Haft-sin table during Nowruz, the Persian New Year.

Sumacs are dioecious shrubs or small trees, growing one to ten meters tall. Their leaves are usually pinnately compound, though some species have trifoliate or simple leaves. The flowers are small, with five petals, and appear in dense panicles or spikes; they can be greenish, creamy white, or red. The fruit is a reddish, thin-fleshed drupe covered in varying amounts of hair at maturity. These drupes cluster at branch tips in dense formations sometimes called sumac bobs. Sumacs spread by seed—dispersed by birds and other animals through droppings—and by new shoots from rhizomes, forming large clonal colonies.

The word "sumac" comes from Old French *sumac* (13th century), from Medieval Latin *sumach*, from Arabic *summāq*, and ultimately from Syriac *summāqa*, meaning "red." The genus name *Rhus* is from Ancient Greek *ῥοῦς* (*rhous*), referring to the type species *R. coriaria*, though its origin is unknown; a proposed link to the verb *ῥέω* ("to flow") is now rejected. The taxonomy of *Rhus* has a long history. In 1825, de Candolle proposed a subgeneric classification with five sections. At its broadest, *Rhus* contained over 250 species, making it the largest genus in Anacardiaceae. Some authors later placed species into separate genera, leading to the terms *Rhus sensu lato* and *Rhus sensu stricto* (s.s.). One classification divides *Rhus* into two subgenera: *Rhus* (about 10 species) and *Lobadium* (about 25 species), while segregating genera such as *Cotinus*, *Duckera*, *Malosma*, *Metopium*, *Searsia*, and *Toxicodendron* to create *Rhus* s.s. Other segregated genera include *Actinocheita* and *Baronia*. Molecular phylogeny research suggests *Rhus* s.s. is monophyletic, but the subgenera are not. The larger subgenus, *Lobadium*, is further divided into sections *Lobadium*, *Terebinthifolia*, and *Styphonia* (with two subsections).

As of November 2024, Plants of the World Online accepts 54 species. In Asia, North Africa, and southern Europe, species include *Rhus amherstensis*, *R. chinensis* (Chinese sumac), *R. coriaria* (Sicilian or tanner's sumac), *R. dhuna*, *R. potaninii* (Potanin's lacquer tree or Chinese varnish tree), *R. punjabensis*, *R. taishanensis*, *R. teniana*, and *R. wilsonii*. In Australia and the Pacific, species include *R. caudata*, *R. lamprocarpa*, *R. lenticellosa*, *R. linguata*, *R. sandwicensis* (neneleau or Hawaiian sumac), and *R. taitensis* (found from northeast Australia to Malesia, Micronesia, and French Polynesia). North American species are also present. One species formerly placed here is *Searsia mysorensis* (as *Rhus mysorensis*), known as Mysore sumac.

Several sumac species are grown ornamentally, including fragrant sumac (*R. aromatica*), littleleaf sumac (*R. microphylla*), smooth sumac (*R. glabra*), and staghorn sumac (*R. typhina*), either as wild types or cultivars. In cooking, the dried fruits of some species are ground into a tangy, crimson spice popular in many countries. The fruits are also used to make a traditional "pink lemonade" by steeping them in water, straining to remove the hairs (which can irritate the mouth or throat), and sometimes adding honey or sugar. Sumac's tart flavor comes from high levels of malic acid. The drupes of *R. coriaria* are ground into a reddish-purple powder used as a spice to add a lemony taste to salads or meat. In Middle Eastern cuisine, it garnishes meze dishes like hummus and tashi, and is added to falafel. It is a main ingredient in Kubah Sumakieh in Aleppo, Syria, added to salads in the Levant, and a key component of the Palestinian dish musakhan. In Afghan, Armenian, Iraqi, Iranian, and Mizrahi Jewish cuisines, sumac is added to rice and grilled meats. In Armenian, Azerbaijani, Central Asian, Syrian, Iraqi, Jordanian, Palestinian, Israeli, Lebanese, Turkish, and Kurdish cuisines, it is used in salads and lahmajoun. Sumac from *R. coriaria* is also part of the Levantine spice blend za'atar. In medieval Europe (13th to 15th centuries), sumac appeared frequently in cookbooks of the affluent; a stew called *sumāqiyya* was often rendered as "somacchia" by Europeans. In North America, smooth sumac, three-leaf sumac (*R. trilobata*), and staghorn sumac are sometimes used to make "sumac-ade," "Indian lemonade," or "rhus juice" by soaking the drupes in cool water, rubbing them, straining through cloth, and sweetening. Native Americans also mix the leaves and drupes of these sumacs with tobacco in traditional smoking mixtures.

The leaves and bark of most sumac species are high in tannins and have been used worldwide in leather manufacturing. The Hebrew name *og ha-bursaka'im* means "tanner's sumac," matching the Latin name *R. coriaria*. The leaves of certain sumacs are also used as a dye.