I have written this brief profile as a result of some confusion on social media as to whether Field Horsetail Equisetum arvense is edible. And to whether there could be a problem with consuming too much of it.
I list the research that I have briefly done, along with citing sources for traditional food use as well as any potential toxicity problems.
Horsetail to many foragers in the UK is considered edible. In this instance I am specifically referring to the use of Equisetum arvense, which can be confused with Equisetum palustre (potentially toxic, see Mills and Bone) and Equisetum pratense.
Caution is advised to make certain you are harvesting E. arvense. Note: It is illegal to dig up roots without landowner’s consent.
And even then there has been little research conducted on long term consumption of this species.
It has however traditionally been eaten around the world. Most notably in Japan and by Native American cultures.
Facciola writes “In Japan the young spore bearing stems are boiled and eaten as a potherb. They are also simmered in soy sauce and mirin to make a dish called Tsukudani.”
According to Uphof the Kiowa Indians used the base of the plant as food.
A problem in a lot of the ethnobotanical literature is how one interprets what the writer is meaning.
“The base of the plant” could mean different things to different people. Even if to you it sounds obvious.
An example of this is an author who states that the roots of E. arvense are edible raw.
I decided to check his source material, as I own the very same edition of the book he cites.
Nowhere in the eight line description of the uses of E. arvense does it say the roots can be eaten raw.
It is purely an assumption on the part of the author. What it actually says. And I quote it word for word is this “… and the rhizomes are eaten by the Indians of N. Mexico.”
Either I am missing something or the author has a serious case of “observer bias”!
According to Kari the tubers are eaten. We don’t know whether they were cooked or consumed raw.
A section in Ethnobotany of the Eskimos of Nelson Island mentions the following “E. arvense L has black edible nodules attached to its roots. The effort of collecting them is considerable and therefore rarely done. However, these nodules are often obtained from underground caches of roots and tubers collected by lemmings and other tundra rodents. These caches of “mouse nuts” are raided by the Eskimos and eaten.”
Turner tells us the tender young shoots were eaten raw or boiled by the Saanich. They were thought to be “good for the blood” as well as nourishing.
According to Sudan, E. arvense was reported to cause skin dermatitis in people allergic to tobacco smoke.
Mills and Bone state, “Theoretically, excessive consumption of horsetail (note: they are referring to E arvense) may lead to thiamine deficiency (deficiency of a vitamin), decrease of body potassium content and nicotine toxicity. Has been reported to cause dermatitis.”
They also mention that “Toxicity is possible from eating large amounts of E. arvense“.
What Does Robin Do?
- Personally I will only consume a small portion of this plant, usually around once a year.
- The window of opportunity to gather is small before it becomes tough.
- I will always cook it.
- Just so you know, I haven’t experimented with it that much.
CONSUME AT YOUR OWN RISK!
- Common name: Field Horsetail
- Scientific name: Equisetum arvense
- Family: Equisetaceae
References
Ager, Thomas A, and Lynn Ager Wallen. Ethnobotany Of The Eskimos Of Nelson Island, Alaska. 1st ed. Columbus, Ohio: Ohio State University, Institute of Polar Studies, 1980. Print.
Facciola, S. (1998). Cornucopia II. 1st ed. Vista, CA: Kampong Publications.
Kari, P.R., 1985. Upper Tanana Ethnobotany. Alaska Historical Commission.
Mills, S. and Bone, K. (2005). The essential guide to herbal safety. 1st ed. St. Louis, Mo.: Elsevier Churchill Livingstone.
Sudan, B. (1985). Seborrhoeic dermatitis induced by nicotine of horsetails (Equisetum arvense L.). Contact Dermatitis, 13(3), pp.201-202.
Turner, Nancy Chapman, and Marcus A. M. Bell. “The Ethnobotany Of The Coast Salish Indians Of Vancouver Island”. Economic Botany 25.1 (1971): 63-99
Uphof, J. (1968). Dictionary of economic plants. 1st ed. Lehre: J. Cramer.
Photo Credit
“Equisetum arvense” by F. Lamiot is licensed under CC BY 2.5
Good article. I struggle with the same sort of thing in a lot of cases. Has the author REALLY tried this him/herself? or are they just copying other information (perhaps incorrectly)?
Liz: I’ve no idea. I would suspect he’s tried them himself, but who knows.
From “plants that we eat” by Anore Jones, regarding the small tuberous growths from mouse or vole caches: “eat raw with seal oil. They are white, crisp and sweet inside the black skin. Because they are so tiny, people chew them hull and all. They are a tedious food to prepare but make a nice little taste treat.”
Thanks Trent. Will take a look at Anore Jones’ book.
It’s a fun book, full of Alaskan natives stories about the foods that they forage. Most common recipe: Mix with seal fat and eat! Only downside is that all the pictures are drawings of so-so quality.
Samuel Thayer’s books are good ones for this. He feels very strongly about having personal experience harvesting, preparing and consuming a plant before telling others to do so and has actually debunked/corrected information in other books by learning about it the hard way. I believe Thomas J Elpel’s foraging book is all based on personal experience too. Once you’ve bought a half-dozen or so plant books it becomes really obvious which ones are based primarily in experience and which ones are just cribbing from other books. I have one, “Edible and Medicinal Plants of Canada”, that I only refer to when I want a good laugh. It has huge disclaimers everywhere because nobody has tested any of the claims in it, and it includes remedies for things like “long periods of celibacy” and “annoying visitors who won’t leave”.
Oh, I should correct, the terrible book is actually “Western Medicinal Plants and Herbs”. I think “Edible and Medicinal Plants of Canada” is also a book of unverified information but not quite to that extent. 🙂
Moerman lists ~
Hopi: (E. laevigatum) “Dried, ground plant used for ceremonial bread.”
Makah: (E. hyemale)”Raw shoots chewed for diarrhea”
Iroquois: (E. arvense) “Raw shoots chewed by teething babies”
In the Encyclopedia of Edible Plants of North America, Francois Couplan writes “They are edible raw or cooked while they are still tender and juicy.” In the introduction to the same book Jim Duke reports of Francois’ extensive personal experience foraging in North America, and Francois reports their taste as “fairly mild”. He writes that the Japanese eat them raw in salads as vegetables or pickled. He warns that mature plants can be toxic and recommends ingesting small amounts only due to thiaminase.
The book is copyright 1998 and there is at lease one plant in there that he reports as edible that I know to be nephrotoxic, so I am not sure how current his data are.
Thanks David… Francois’ book is very old. I need to take a look at his French language books as they are more recent. Personally horsetail is more a medicine to me.
Is it a fungus i thought Equisetum arvense was a plant have been taking it a herbal tea?
Sue: Yes horsetail is a ‘plant’.
What a fabulous answer. Thanks for your time and knowledge.
I know of an old lady in Italy who dries equisetum leaves and sprinkles a tiny quantity as condiment on her food to relieve her arthritis. For cooking the shoots the boiling water should be changed several times to remove any toxins. Haven’t tried myself though.
I’ve done the same for years. Just harvested a bunch that will last me at least a year.
Just tried some raw
Stems are rather like bean sprouts in consistency…and slightly sweet. The bulbous ends are much more bitter- and had to be spat out!
Not sure it’s with the bother of consuming quantities from a purely gastronomic point of view!
I’m Japanese and I grew up eating the young shoots with spores. It’s a delicacy in spring. I used to go collect them with my parents. The way we prepare them is to take the rough brown papery part off the stem — we call that portion “hakama” but it’s basically papery thing attached to nodes. We wash it and blanch it quickly in hot water, then drain. We then sautee it with soysauce, mirin, sake and sugar, then put egg in at the end. Japanese name for this dish is Tsukushi-no-tamagotoji. Serve over rice. It’s super yummy. It’s similar in flavor profile to oyako-don if you are familiar with Japanese cuisine. Hope this helps.
Hi Yoshika – Wonderful to hear how you use the plant. Many thanks for your insightful comment.
It is not Tsudukani
The correct name is Tsukudani.
Thanks for pointing that out Am. I’ve amended the entry above.
I dry out Horsetail and put a little in my morning smoothie. Had silica for your bones.
I just moved to Nova Scotia and I am living out in the country, I enjoy foraging my land for herbal remedies such as Chaga, Turkey tail, Birtch Pollyor and so many mushrooms. I thought I was wild asparagus, not able to figure out what I have with the wonderful service and just take a photo and I will not kill myself. TXS
In Japan, my family would pick the shoots in early spring before the heads had started to open and become dusty with spores. Lay them out in ash from the hibachi for a while. I don’t know why. I’m guessing the ash was alkaline, or perhaps it just drew the water out of the stem. Then we’d either fry them as tempura, or saute them in oil and serve with shoyu sauce.
They were one of the bitter herbs of spring [??(Sansai)]. The reducing the bitterness was called ??? (Akutori)
There is a saying, “??????????” (Haru no sara niwa Nigami o more) which literally means “Serve bitter taste on a plate in spring” meaning that a bitter taste in spring is good for our health/effective for detoxification in order to remove the waste of body accumulated during the winter.
Sorry, your website does not render Japanese characters see question marks instead (above).