The Abundant Acorn

The Abundant Acorn

by Torrey Douglass


Acorns are amazing. You could easily overlook these little oblong nuggets scattered among the duff under oaks, but they are an integral part of our ecosystem, a nutrient-rich food source for all sorts of wildlife, from squirrels and wild turkeys to deer and wild pigs. In a 2014 article in Scientific American, ecologist Janet Fryer from the U.S. Department of Agriculture Forest Service states that “oak species with their large, nutrient-rich acorns, may be the single most important genus used by wildlife for food and cover in California forests and rangelands.” Even domesticated livestock like cows, sheep, and goats will feed on acorns from the many types of oaks that thrive on our south facing slopes.

Like many California natives, the Pomo people of our area relied on acorns as a dietary staple. And why not? They are an excellent source of fats, protein, and minerals, and thanks to their hard outer shells, they can be stored for up to three years. Health benefits include improving digestion, heart health, energy levels, and blood sugar regulation—quite the superfood! And super-abundant as well. A mature oak can drop up to 2,000 pounds of acorns in a good year, but as Boonville homesteader Rob Goodell shared, an oak’s yield can vary greatly from one year to the next.

So what’s the catch? In a word: tannins. Tannin amounts vary among different oak species, with white oaks containing the least. (Some oaks in the area include black oaks, live oaks, and tan bark oaks.) It’s best to collect the acorns shortly after they’ve fallen, while there’s still a little give to the shells. Moth worms can burrow into acorns, leaving a hole that lets in air, so to quickly identify infected acorns, pour a bunch in a bucket of water and remove the “floaters.”

To render the acorns edible, tannins need to be removed through either steaming or soaking. The first step for either process is to remove the acorns from their shell. You can lay out the acorns inside a folded towel then hit them with a hammer to crack the shells. You can also soak them overnight to soften the shells, then peel them by hand. Fastidious cooks remove the papery layer between the shell and nut, but it’s not necessary. After you’ve gathered the nut meats, chop them roughly in a blender. Do not make them too fine or they will fall through the holes in your steamer.

Next, place three to four cups of the chunky acorn mush into a steamer. After 30 minutes, taste to check if enough tannins have steamed out. It can take up to two hours for full processing, so keep tasting until you’re satisfied the bitterness is gone.

Another leaching technique requires storing the chopped acorns in a large glass jar of water in your fridge. Drain and replace with fresh water every day for a week, then taste to see if they are ready or give them more time if they need it. In the past, the native Pomo would fill a basket with acorns and set it in a running stream for a couple of weeks to achieve the same effect.

Once the tannins are removed, you can work with your acorn mixture. A second blend will break down the chunks into smaller pieces for a finer “meal”—this can be done in a blender or with a potato masher. Next spread the meal on cookie sheets to dry in the sun. It needs to be completely dry to become acorn flour or the moisture will accelerate decay. Once dry, you can blend again in a food processor, then sift to remove any last little chunks. Store acorn flour in a dry, dark place. It will last anywhere from a few months to almost a year.

You can use half acorn flour and half wheat flour in your favorite baking recipes, but be mindful that the acorn flour is gluten-free and adjust your approach accordingly. Pancakes, muffins, and even breads work well with acorn flour. The end product is similar to almond flour, so you can expand your options by hunting for almond flour recipes wherever you look for kitchen inspiration.

Willits herbal teacher Donna D’Terra uses acorns to make acorn paté. Learn more about processing acorns in her September 8th class: Autumn Wild Harvest. This hands-on class will also cover a method of turning Bay nuts into chocolate-like treats and using Manzanita and Toyon Berries as drink and seasoning. For more information, 707-459-5030 or

Donna d’Terra’s Acorn Pate

Mix 1 cup acorn (leached, cooked, strained, cooled) with mayonnaise until it is a “spreadable” consistency. Fold in some or all of these (chopped fine): scallions or red onion, celery, basil/cilantro/parsley, toasted sesame or toasted sunflower seeds. Add to taste: lemon juice or balsamic vinegar, tamari, salt, or pepper. Serve on crackers and enjoy! Photo by Andy Balestracci.


Special thanks to Donna d’Terra the recipe.