The pecan (pronounced /pɨˈkɑːn/, /pɨˈkæn/, or /ˈpiːkæn/), Carya illinoinensis or illinoensis, is a species of hickory, native to south-central North America, in Mexico from Coahuila south to Jalisco and Veracruz, in the United States from southern Iowa, Illinois, Missouri, and Indiana east to western Kentucky, North Carolina, South Carolina, and western Tennessee, south through Georgia, Alabama, Mississippi, Louisiana, Texas, Oklahoma, Arkansas, and Florida, and west into New Mexico.
“Pecan” is from an Algonquian word, meaning a nut requiring a stone to crack. It is pronounced in various parts of the US as pi-KAHN, pi-KAN, PEE-kahn, or PEE-kan. In Mexico, pecans and walnuts share the same Spanish name, nuez, which is a cognate of the English word nut.
Pecans were one of the most recently domesticated major crops. Although wild pecans were well-known among the colonial Americans as a delicacy, the commercial growing of pecans in the United States did not begin until the 1880s. Today, the U.S. produces between 80% and 95% of the world’s pecans, with an annual crop of 150–200 thousand tons. The nut harvest for growers is typically around mid-October. Historically, the leading pecan-producing state in the U.S. has been Georgia, followed by Texas, New Mexico and Oklahoma; they are also grown in Arizona, South Carolina and Hawaii. Outside the United States, pecans are grown in Australia, Brazil, China, Israel, Mexico, Peru and South Africa. They can be grown approximately from USDA hardiness zones 5 to 9, provided summers are also hot and humid.
Pecan trees may live and bear edible nuts for more than three hundred years. They are mostly self-incompatible, because most cultivars, being clones derived from wild trees, show incomplete dichogamy. Generally, two or more trees of different cultivars must be present to pollinate each other.
Pecans are a good source of protein and unsaturated fats. Like walnuts (which pecans resemble), pecans are rich in omega-6 fatty acids, although pecans contain about half as much omega-6 as walnuts.
A diet rich in nuts can lower the risk of gallstones in women. The antioxidants and plant sterols found in pecans reduce high cholesterol by reducing the “bad” LDL cholesterol levels.
Clinical research published in the Journal of Nutrition (September 2001) found that eating about a handful of pecans each day may help lower cholesterol levels similar to what is often seen with cholesterol-lowering medications. Research conducted at the University of Georgia has also confirmed that pecans contain plant sterols, which are known for their cholesterol-lowering ability. Pecans may also play a role in neurological health. Eating pecans daily may delay age-related muscle nerve degeneration, according to a study conducted at the University of Massachusetts and published in Current Topics in Nutraceutical Research.
The U.S. Food and Drug Administration (FDA) has acknowledged this and related research and approved the following qualified health claim: “Scientific evidence suggests, but does not prove, that eating 1.5 ounces per day of most nuts, such as pecans, as part of a diet low in saturated fat and cholesterol, may reduce the risk of heart disease.”