Tree nuts have been an important part of the human diet since prehistoric times. While there is extreme diversity among tree nuts, most have in common an edible kernel enclosed in a hard outer shell. (Peanuts, though called โnuts,โ are actually legumes.)
North America is abundantly supplied with indigenous nut-bearing trees, and their fruit has been gathered and consumed since humans arrived thousands of years ago. Acorns and pine nuts, for instance, were an important constituent of the diet of Native Americans, especially California Indians. Pecans were prized by Native Americans in the Midwest and South, and East Coast Indians used butternuts to thicken their soups. Other Native Americans consumed American chestnuts, filberts, hickory nuts, and black walnuts.