Sumacs are shrubs and small trees that can reach a height of 1–10 metres (3.3–33 ft). The leaves are spirally arranged; they are usually pinnately compound, though some species have trifoliate or simple leaves. The fruits form dense clusters of reddish drupes called sumac bobs. The dried drupes of some species are ground to produce a tangy purple spice. Commonly found in North America and Africa, sumac trees grow abundantly in the wild. They are also used for ornamental purposes, due to the attractive fall foliage color.