What plants were gathered as opposed to being grown by past cultures? What other functions did plants serve besides food? These questions are answered by examining the plant remains recovered from archaeological sites. We know that wild plants were harvested for food, to make baskets, cords, shelters, for medicines, and for firewood.
Wild rice from the Mississippi was first harvested by Woodland peoples about 300 AD. But wild rice was most popular with the farming Oneota communities who harvested wild rice from the backwaters of the Mississippi river. Beds of wild rice were present in La Crosse in 1400 AD. Some beds are still present.
Seeds are recovered through flotation, Although charred, ancient seeds are still identifiable by comparison to modern seeds. Fruits included blackberries, cherries, blueberries, grape and sumac. Greens were harvested from wild plants, and goosefoot may have been grown for both greens and seeds.
Hickory nuts and walnuts were important foods for the Archaic and Woodland period and were still used by Oneota peoples. High in protein and oil, they were easy to store for food over the winter.