As the chilly autumnal breezes cause leaves and other flora to “fall,” my attention is brought to those little oaky morsels beloved by squirrels and interior decorators alike: acorns.
This past weekend I had a table at Michigan Archaeology Day at the Michigan History Center. My display was called “Ancient Michigan Meals” and I displayed the various kinds of foods that were present in the archaeological remains at the Cloudman site, including squash, wild rice, maize, and fish. Many adults and children alike were surprised by the acorns also on display. Several kids expressed bewilderment at why people ate what they called “squirrel food”. But these nuts are much more than rodent fodder.
Acorns have been important components of human diet in many regions of the world for millennia. They have been found in large quantities at many archaeological sites across Eastern North America, Mexico, Europe/Mediterranean, and Asia (1). Beginning ca. 3000 BC, many societies in California developed an acorn economy, where acorns become a staple food (2). Many of these societies continued to rely heavily on acorns until the arrival of Europeans. Some have posited that the Natufians, precursors to world’s very first farmers in the Levant, may have also been reliant on acorns, allowing them to become sedentary, or settle in one spot permanently, before developing agriculture (3).
However, having an acorn-heavy diet is no simple task. Unlike other nuts, you cannot just pick them up off the ground and eat them. Well, you could, but you would likely regret it. Acorns contain tannins, organic compounds found a variety of foods, including berries, nuts, legumes, coffee, tea, and wine. Tannins taste bitter and can cause gastrointestinal problems when eaten in large quantities. Acorns contain a LOT of tannins, so to make them edible, they must first be leached.
There are several methods for leaching acorns. Boiling is common leaching method, one that seems to have been preferred by historic-era Ojibwe and Huron. The Ojibwe sometimes boiled acorns whole and then ate them (4), but usually boiled them several times over and then ground them into flour (5). The Huron boiled them in wood ash to neutralize the tannins (6). Most often the acorns were then ground into flour and added to soups as a thickening agent.
Another method for leaching is to essentially wash the tannins out of the acorns. Traditionally, this involves securing a bag of acorns to a fixed spot along a river or stream, which will wash out the tannins over the course of a day or two.
I found out first hand just how labor-intensive simply shelling acorns can be. Barb Barton, a wild foods expert, has been gathering and eating acorns for years, and she recently let me help her process some. The images below depict the shelling process:
Barb replicates the “river” leaching method by putting chopped acorns in a mesh basket at the top of a bucket with a nozzle at the bottom, which she places in the sink with the faucet just barely running for a day or so. The constant, if slow, flow of water eventually leaches the tannins. The acorns bits are then roasted dry and ground into flour.
Acorns take a lot of work. So why were they so popular in the past? If you’ve ever walked through any park with oak trees in late September/early October, you will have seen the massive amounts of acorns that drop from the trees at this time. This means that they would be relatively easy to collect in large quantities, so, as my friend Dr. Kate Frederick points out, that initial labor investment would be low. In places like northern Michigan, acorns could be stored as an emergency food, and accessed in the lean times of later winter/early spring if necessary, when the labor of food preparation would be more than worth it (7).
But acorns were not just emergency food in the Upper Great Lakes and were eaten frequently as an important source of fats and carbohydrates (8, 9). They were frequently cooked in the pottery vessels at the Cloudman site throughout its 1500-year history, demonstrating that the original residents of Michigan were simply nuts about acorns.*
*Note: the phrase “Nuts About Acorns” was shamelessly stolen from the great wise Sean Dunham. Find his paper and dissertation and give them a read!
- Mason, Sarah L. R.
1992 Acorns in Human Subsistence. Ph.D. Dissertation, Institute of Archaeology,
University College, London, United Kingdom.
- Stevens, Nathan E. and Richard McElreath
2015 When are two tools better than one? Mortars, millingslabs, and the California acorn economy. Journal of Anthropological Archaeology 37:100-111.
- McCorriston, Joy
1994 Acorn Eating and Agricultural Origins: California Ethnographies as Analogies for the Ancient Near East. Antiquity 68(258):97-107.
- Densmore, Frances
2005 Strength of the Earth: The Classic Guide to Ojibwe Uses of Native Plants.
Minnesota Historical Society Press, St. Paul.
- Hilger, Inez
1951 Chippewa Child Life and Its Cultural Background. Smithsonian Institution Bureau of American Ethnology Bulletin 146. Governement Printing Office, Washington, D.C.
- Tooker, Elisabeth
1991 An Ethnography of the Huron Indians, 1615-1649. Syracuse University Press,
Syracuse, New York.
- Frederick, Kathryn
2018 Food Storage, Decision-Making, and Risk Management in Non-Sedentary Societies. Ph.D. dissertation, Department of Anthropology, Michigan State University, East Lansing.
- Dunham, Sean B.
2009 Nuts about Acorns: A Pilot Study on Acorn Use in Woodland Period Subsistence in the Eastern Upper Peninsula of Michigan. The Wisconsin Archeologist 90(1-2):113-130.
- Dunham, Sean B.
2014 Late Woodland Settlement and Subsistence Patterns in the Eastern Upper Peninsula Of Michigan. Ph.D dissertation, Department of Anthropology, Michigan State University, East Lansing.