The pecan (Carya illinoinensis) is a large deciduous nut tree in the hickory family, native to the Mississippi River valley and the southern United States. Pecans are the most economically important native North American nut crop and are widely planted as both a commercial crop and a homestead shade and nut tree. The tree is long-lived, with productive lifespans of 80 to 100 years, and produces a rich, buttery nut that is one of the most popular tree nuts in the United States.
Pecans were harvested by Native American peoples for thousands of years before European contact. The word "pecan" comes from the Algonquian word pakani. The tree's native range extends from the Mississippi River west to Kansas and Texas and south to the Gulf of Mexico. Pecans were an important food source for indigenous peoples, who traded the nuts along established routes.
The first pecan was successfully grafted in 1846 by a Louisiana slave gardener named Antoine. This tree, known as the Centennial pecan, was the first improved variety and established the practice of growing named varieties through grafting. The commercial pecan industry developed in the late 19th century, centered in Georgia, Texas, Oklahoma, and New Mexico.
Pecan trees are among the largest nut trees, growing 70 to 100 feet (21 to 30 meters) tall with a spread of 60 to 80 feet (18 to 24 meters). The leaves are compound, 12 to 20 inches (30 to 50 centimeters) long. The nuts are oblong, 1.5 to 2.5 inches (4 to 6 centimeters) long, with a thin shell and sweet, high-oil kernel. The shell color varies from light brown to dark brown.
Pecans require 80 to 140 frost-free days for nut development. They are adapted to warm, humid climates and are not reliably productive north of USDA zone 6. Most pecan varieties require cross-pollination from a compatible pollinator variety. The trees are deep-rooted and drought-tolerant once established. A mature pecan tree yields 50 to 150 pounds (23 to 68 kilograms) of nuts in a good year, though production is alternate-bearing.
Pecan trees are grown for nut production and as shade trees on homesteads within their range. The nuts are consumed fresh, roasted, and in baked goods. Pecan pie is a traditional southern dessert. The trees provide deep shade and produce high-value timber at the end of their productive life.
The large size of mature pecan trees limits their suitability for small properties. Pecans are susceptible to pecan scab and require fungicide applications for reliable nut production in humid regions. Weed control and alternate bearing patterns also affect annual yields.