Almonds, Brazil nuts, hazelnuts, macadamia nuts, pecans, pistachios, and walnuts are all tree nuts. Though many consumers lump all nuts into one category, peanuts are not considered tree nuts, as they are a legume.
Produced on less than two percent of the nation’s agricultural cropland, the United States still harvests a vast amount of tree nuts each year. Georgia, New Mexico, and Texas dominate in pecan production while California continues to produce the lion’s share of almonds, pistachios, and walnuts. Tree nuts are also among California’s top exports.
While the chestnut is considered a tree nut, this commodity is covered in a separate Know Your Commodity profile.
References: Agricultural Marketing Resource Center, USDA.
TYPES, VARIETIES & CUTS
California is the only U.S. state that grows almonds commercially, and most production is exported across the globe. There are several varieties of almonds including Mission, Nonpareil, Price, Butte, and Padre.
As the nut forms on the tree, it is enclosed in a sturdy hull and an inner hard shell. Although almonds are sometimes sold in-shell, they are more often shelled during processing. The product may be further processed through blanching, dry roasting, chopping, or converted into a paste called marzipan—a confection made from honey, sugar, and almond meal.
Brazil nuts grow on the Bertholletia excelsa tree native to the South American Amazon forest. Growing up to 160 feet high with a trunk diameter of three to six feet wide, the Brazil nut is the largest tree in the Amazon forest. The majority of Brazil nuts are produced in Bolivia, followed by Peru and Brazil.
Generally eaten raw, Brazil nuts are a good source of protein, magnesium, and Vitamin E, and are extremely rich in selenium, a powerful antioxidant. However, people who regularly eat too many Brazil nuts can suffer from selenium poisoning. For this reason, it is recommended consumers eat no more than two or three Brazil nuts per day.
Also called filberts, hazelnuts originated from the Black Sea and Mediterranean regions in Turkey, Italy, and Spain. This area is still the center of production, with Turkey producing more than half of all hazelnuts in the world. The United States ranks third in production after Turkey and Italy.
Although a small portion of hazelnuts are grown in Washington State, Oregon is responsible for nearly all U.S. production. The only tree nut produced commercially in Oregon, hazelnuts are an important crop and frequently featured in confections such as chocolate truffles, cookies, pralines, and chocolate-hazelnut spreads. A popular commodity for the snack food industry, hazelnuts are sold whole, diced, ground, unshelled, or as a paste or oil.
Macadamia nuts originated in Australia in the mid-1800s and were later introduced to Hawaii in 1881. Though found in tropical and subtropical countries across the world, the round nuts are only commercially produced in Australia and Hawaii.
Two primary species, Macadamia integrifolia and Macadamia tetraphylla, are both native to Australia. Also known as the “smooth shell” species, the integrifolia is grown in Hawaii and produces a round, small nut with high oil content—a characteristic that makes it better for roasting and salting. Tetraphylla, the “rough shelled” species, is less tolerant of extreme temperatures but produces a sweeter tasting nut. Considered a gourmet nut, whole macadamias are sold salted in glass jars or used in cookies and candies.