For centuries, acorns have been a major food source for many California Indian groups. Nutritious and easy to store, processed acorns could be served as soup, mixed with fruit or meat, or baked into a cake.
1. In autumn, Indian people filled their carrying baskets with acorns from beneath the oak trees.
2. They cracked and shelled the dried acorns. Following time-honored practices, they pounded the acorn meat into meal using bedrock mortars - holes worn into slabs of rock.
3. The acorn meal was then transferred to a shallow, sandy basin lined with leaves or grass where water was gently poured over the meal to wash out the bitter tannic acid.
4. Finally, the meal was mixed with water in large baskets to form a soup or mush and cooked by heated rocks placed into the baskets.
In good harvest years surplus acorns were traded to other Indians groups in exchange for useful goods - such as shells, skins, stone and pine nuts - that were abundant in other regions.