Any species of the genus Carya, formerly known botanically as Hicoria. Hickories are mostly tall forest trees characterized by strong, terminal, scaly winter buds; pinnately compound leaves (see illustration); solid piths (not chambered); and fruit with an outer husk or exocarp, which splits more or less readily into four parts, revealing a nut with a hard shell or endocarp. See also: Fagales; Fruit; Nut crop culture
The shagbark hickory (C. ovata) grows to a height of about 120 ft (36 m) and is found in the eastern half of the United States and adjacent Canada. It is the most important species because of the commercial value of its nuts—the hickory nuts of commerce—and of its wood. It is recognized easily by the bark, which in older trees exfoliates from the trunk in long, curving, irregular plates, and by the leaves, which usually have five leaflets, of which the terminal one is larger.
The pecan (C. illinoensis) is also a valuable species because of its commercially popular, thin-shelled, sweet nuts. Although the native range is limited to the Mississippi Valley region and Mexico, many varieties are cultivated in the southern United States. Other species include the mockernut hickory (C. tomentosa) and pignut hickory (C. glabra), which are distributed widely through the eastern half of the United States, and the shellbark hickory (C. laciniosa), which is found in the east-central United States. See also: Pecan
The remarkably tough and strong wood of all species makes it the world's best wood for tool handles. For example, the Janka hardness for C. illinoensis is 1820 lb-force (826 kg-force); its density is 51 lb/ft3 (817 kg/m3). Hickory wood is also used for parts of vehicles, furniture, flooring, boxes, and crates, and for smoking meats. See also: Forest and forestry; Tree