Ambrosia trifida, once cultivated for grain, photo by Illinois Wild Flowers

Ambrosia trifida, once cultivated for grain, photo by Illinois Wild Flowers

Some 18 generations ago — 600 years ago give or take a few centuries — some Natives Americans stopped cultivating a particular crop and may have moved on to maize. About 150 years ago — five generations — American farmers were raising crabgrass for grain when they, too, moved on to corn, the descendant of maize. So what crop did the Indians stop growing? Ragweed, the most hay-fever causing plant in the world. No one alive knows why Ragweed fell out of cultivation though the development of maize is a prime guess. And Ragweed certainly is not  favored by farmers now who view it as a vile invader that chokes domestic crops. Perhaps it’s time to reconsider Ragweed.

Common Ragweed, photo by Wisconsin Plants

Common Ragweed, photo by Wisconsin Plants

The grain is some 47% crude protein and 38% crude fat. That’s an energy powerhouse despite the size. The seed oil is edible and at least one person alive today has eaten a small hand full of seeds. They taste like wheat brand.  In excess of 5,000 seeds can be produce per plant. Generally said Ragweed is not an “antique vegetable” as such things are sometime called. But, it might be a lost grain. Ragweed oil is on par with soybean oil and the plant produces about the same amount as soybean, one fifth the seed weight. Some reports say natives would grind the seeds, bring them to boil in water, the oil would float to the top, then was ladle off.

Ragweed seed, photo by USDA

Ragweed seed, photo by USDA

While one could argue this is much to do over some oil but fat, saturated or unsaturated, is essential to survival. You absolutely cannot live without some source of fat. Oil would have been extremely important to native populations and could be again if we were ever forced to provide our own food. And unlike soybean which has to be cultivated, Ragweed is a weed that can do all right on its own. One debate in the ethnobotanical community is whether the natives cultivated a huge version of Giant Ragweed or not. One study says yes because the seeds that were found were larger than found in nature. Another study says no reporting that there are large seeds in nature as well. Bit of a toss up there. But we know animals certainly ate them and still do. In fact Ragweed is one of the few seed-bearing plants that stands above deep snow providing valuable food during the winter. It’s on the menu for the Eastern Cottontail, Meadow Vole, grasshoppers which eat the leaves, Dark-eyed Junco, Brown-headed Cowbird, Northern Bobwhite, Purple Finch, Mourning Dove, American Goldfinch, and the Red-bellied Woodpecker. Sheep and horses also like to eat the plant. What about humans eating the hard seeds? There’s a lot of speculation but few hard facts.

The author Peter Goodchild reports giant ragwee seeds were a source of grain

The author Peter Goodchild reports giant ragwee seeds were a source of grain

An article on the plant at Michigan State University for the W.J.Beal Botanical Garden says: “…some archaeologists have suggested that …  the seeds were impractical as a food source. However, the fact that Indigenous Americans were specialists at navigating starvation episodes, combined with the observation that giant ragweed seeds are comprised of about 19 percent edible oil, make it fairly certain that these seeds would not be overlooked as a food resource.” No details given. A weed ecology fact sheet for Ohio State University says: “One of our few native weeds. Seeds eaten by pre-Columbian Indians.” Again, no details. In the book Archaic Societies: Diversity and Complexity Across the Midcontinent by Thomas E. Edison (2009) it mentions a 1997 it report (Gremillion) that ragweed seeds were found in paleofecal material from 950 to 1400 years ago along with sunflower seeds and sumpweed seeds. It’s difficult for a seed to end up in an ancient bathroom unless it was eaten. In 1984 Peter Goodchild published Survival Skills of the North American Indians.  On page 209 in a list of  “food plants” he writes for the Giant Ragweed “cultivated for its seed in several areas.

Was Giant Ragweed cultivated? It would seem so, and for its grain. It’s definitely in the ancient farmers crop line up but then falls away. The next question is was it to eat the grain or for the oil, or both? It is easy in modern times to be aware of past practices. For example, some suggest the natives crush the seeds and boiled them for oil (not unlike acorns.) Possible yes, but is it probable this was done for food? In communication with Goodchild he writes:

“Judging from other uses of oily seeds, the natives are unlikely to have done any processing of the seeds. Generally that’s not practical without modern machinery. I’ve even experimented myself with sunflower seeds, and found no practical (primitive) method of getting the oil out — it’s far easier just to eat the seeds”

Author Peter Goodchild

Author Peter Goodchild

Thus while the seeds have oil its extraction might not have been the prime use whereas eating the grain could have been. But might I offer a variant of that? From a calories-in calories-out point of view — or level of difficulty — many ancient foods would not be consumed. They just were not worth the effort as food. Among them could be smilax root starch and pokeweed greens. Getting the starch out of a smilax root is a Herculean task that burns far more calories than is produced. And boiling pokeweed twice does not make caloric sense when boiling was difficult and other nutritious leaves could be eaten raw.  What  I suspect was whilst in the pursuit of medicine  — which is not a calories-in calories-out dependant task — it was discovered various plants had other edible parts. Medicinal needs could justify calorie-deficit tasks. And while fat was obtainable from animals a plant oil might have its medicinal applications. So perhaps the Giant Ragweed could have been used for food and for oil but the latter in a medicinal sense. Ragweed oil might have been too valuable to eat but worth the effort to obtain medicinally. Another possible aspect professional Archaeologists never seem to consider is that long ago the menu changed only with the seasons. They would dismiss Giant Ragweed grains as too small or not worth the effort to make a stable crop, and that may be true. But they were another flavor and texture to add to the limited, slow-to-change diet. We sprinkle pine nuts on pesto. Might they have done something similar?

Ragweed Pollen

Ragweed Pollen

As for allergens, Ragweed is second only to mold in causing allergic symptoms. There are 17 species of Ragweed in North America. The common ragweed (Ambrosia artemisiifolia) can produce a million grains of pollen per plant daily, the Giant Ragweed (Ambrosia trifida) can create in excess of 1.25 million grains daily and over a billion during its life cycle. This leads to a lot of cross pollination and plant variation. Left on its own Ragweed is a riparian plant living along rivers and local flood plains. Isolated patches depend upon the wind to carry the pollen. With the migration of man so went the Ragweed and the number of plants and the amount of pollen carried by the wind. Ragweed has multiple antigens but the strongest is Antigen E. There are also several plants that in the greater Ragweed family that can cause allergic reactions including sage brush, marsh elders, poverty weed, cocklebur, desert broom, groundsel bush, feverfew and dog fennel. Goldenrod is unfairly blamed for causing allergies because it blooms at the same time as Ragweed. But, its pollen is too heavy to be windblown. (Here’s a botanical hint: Green flowers, in particular small green flowers, are usually wind-pollinated. They aren’t colorful enugh to attract insects for pollination.)

Ambrosia tenuifolia has edible roots.

Ambrosia tenuifolia has edible roots.

There is also at least one Ragweed with a root the natives ate, Ambrosia tenuifolia, Slimleaf Burr Ragweed. Professor Daniel Moerman reports the Papago Indians dried the roots in the sun and used them as a staple crop (that would be in Arizona.) They also ate the stalks as greens. However the USDA lists Ambrosia tenuifolia as only growing in Louisiana and Puerto Rico. That particular Ragweed it is native to South America and has been naturalized in Spain, France and Italy. Why it is missing from Arizona now is anyone’s guess. Elsewhere natives used Ragweed stalks for rope. The stems and leaves of  Ambrosia peruviana were and are used as a green dye. Various species were also used medicinally, see Herb Blurb below.

The Greek Gods consumed ambrosia and see what it did for them!

The Greek Gods consumed ambrosia and see what it did for them!

As for the binomial name, Ambrosia is usually translated into English as meaning “food of the gods.”  A direct translation from the Greek means “unmortal”  or “not mortal.” In Greek mythology “ambrosia” was sometimes the food the gods ate and or wine they drank which gave the gods (and demigods) immortality thus called “ambrosia.” But, food and drink were used interchangeably thus for some ancient writers “ambrosia” was food and for others it was drink which was also called nectar, Greek NEKtar which means “death overcoming.” Ambrosia is close to the older Sanskrit word Amrita which means “without death.” Clearly there was a long-running theme here. Greek gods, who always had human failings and consequently were far from perfect, were what they ate and drank, not unlike people today. Why a rather nondescript plant that is a prime allergen would be called Ambrosia is anyone’s guess. No hints were left.

One more thing. The common ragweed, Ambrosia artemisiifolia, is the most efficient plant to remove lead from the ground.

Green Deane’s Itemized Plant Profile: Giant Ragweed

IDENTIFICATION: Annual 3 to 12 fee tall, branching occasionally. Green stems covered with white hairs, leaves opposite to a foot long and eight inches wide,  larger leaves divided into 3 or 5 lobes, usually serrated along the edge, long petioles sometimes winged. Smaller leaves near the base of flower lance-shaped, often hairy underneath. Upper stems terminate in a cylindrical flower spike to six inches long. Small flowers yellowish green, no petals or sepals, drooping clusters.

TIME OF YEAR: Flowers late summer or early fall, seeds follow, large, tough-coated, viable for many years.

ENVIRONEMENT:  Full sun to light shade, moist, fertile soil. It is native to 47 of the 50 states missing Nevada, Hawaii, and Alaska.

METHOD OF PREPARATION: We have no idea. Perhaps ground seeds boiled in water, oil skimmed off the top. Perhaps the seeds were parched then eaten. A few can be eaten raw. Beyond that there is no modern report of modern consumption.

Herb Blurb

Te genus yields volatile oils. quercetin, and bitter alkaloids. Plant extracts are anti-bacterial and anti-viral. Ambrosia ambrosioides; a tea was made from the roots and given to women after birth. Ambrosia confertiflora; used to cure diarrhea, flowerettes chewed and followed by a drink of water. Ambrosia cumanensis; herb teas for yellow fever, constipation, menorrhagia. Herb juice for pleurisy. Root or herb infusions for colds, flu, fever, in postpartum depurants. Herb of second growth crushed leaves mixed with chicken fat and/or hot water, cool mixture rubbed on the body to reduce fever.  Ambrosia elatior as a poultice. Ambrosia hispida was used to relieve fever, stomach ache, pain, loss of appetite, and flu. To boiled leaf tea they added salt to to increase the appetite then drank the tea for nine mornings. Lemon juice and salt was added when it was used for gas and colds. A weak leaf tea with salt was used to relieve menstrual pain (again taken for nine mornings.) It was also a “granny” medicine to “clean everything out” after childbirth. Tea from fresh plant less better than tea from dried plant. Ambrosia psilostachya, a bitter decoction taken to relieve fever.

Journal of Northeast Forestry University 2008-01
GC-MS Analysis of Fatty Acid Constituents in Ambrosia trifida Seed Oil

Zhang Lin,Yang Lei,Niu Huiying,Li Xiaowei,Zu Yuangang(Key Laboratory of Forest Plant Ecology of Ministry of Education,Northeast Forestry University,Harbin 150040,P.R China)

Seed oil extracted from the seeds of Ambrosia trifida through solvent extraction was analysed by GC-MS after esterification. Four components from six peaks of the fatty acid constituents were identified.The main constituents are linoleic acid and oleic acid,and the relative contents are 81.60% and 14.73%,respectively.

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{ 23 comments… read them below or add one }

1 Barbara Schanel February 11, 2013 at 09:27

I’m pretty sure we have Ambrosia tenuifolia in our yard here in Tennessee. It grows all through our garden and is easily mistaken for the marigolds I plant to inhibit root nematodes. The other day my husband and I were discussing what uses ragweed must surely have so this article is very timely for us. Has it ever been used as a fiber plant?

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2 Brian February 13, 2013 at 15:53

Ambrosia trifida grows all over the place around here: Dallas, Texas. It makes for a fair hand drill spindle. I have also used it for bow drill, the spindle & hearth, with success.

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3 Thomas March 7, 2013 at 10:37

Amazing article. I work on a split-operation half-organic farm in Manatee County Florida. Common Ragweed is the most prolific “weed” growing between our crop rows. We try to look at weeds as a response mechanism to improve the soil and the fact that it removes lead makes me wonder if that’s part of why we have so much of it.

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4 RM McWilliams March 10, 2013 at 20:43

Interesting thought. If you can afford to have the ragweed from your soil tested, we would greatly appreciate your sharing the results. Maybe a bright young student would be interested in including your ragweed in their studies, as bio-remediation of toxins in soils and water is very much in vogue in the academic world.

I have seen ragweeds thrive on rich soils that were unlikely to have had high levels of lead, but I do not have anyalysis on those soils proving this.

Another interesting question is: how available is the lead accumulated in the ragweed to humans or animals consuming various portions of the plant?

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5 April lewis March 7, 2013 at 17:17

Does any one know if Ragweed seeds have gluten in it?

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6 RM McWilliams March 10, 2013 at 20:27

Those sensitive to gluten would be well advised to learn the natural sources of gluten and also possible gluten contamination of other foodstuffs and/or processed foods to which gluten has been added. Apparently gluten can be used as an additive to stabilize food products without appearing on the label under current labeling requirements.

Naturally, gluten occurs only in cereal grains of the grass family including wheat and closely related species: barley, rye, and triticale (a hybrid cross of wheat and rye). Some variaties of oats may contain gluten, but storage and handling of grains and grain products can lead to glutens from other grains appearing in the oats.

Maize (corn) and rice do not contain true gluten (unless contaminated in handling/processing or if gluten is used as an additive to foods containing corn or rice).

Anyone might have or develop a sensitivity to essentially any food. BUT, ragweed is not a plant in the grass family; ragweed seeds are not cereal grains; and ragweed seeds do not contain gluten.

Finding reliable information on topics that affect our lives is an important life skill for those of us living in the ‘misInformation Age’. But it is something that we should all learn to do for ourselves, particularly where our health is concerned. Please do not take my word for anything, but check all information for yourself. Best wishes.

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7 Kara March 28, 2013 at 08:59

Interestingly, my dogs love giant ragweed. There is a large patch of it growing on an empty lot on our street and whenever we walk past it the dogs yank us over to it so they can graze on it. We didn’t teach them this behavior at all, but our dog that might be part wolf honed in on it the first time he saw it. They tear the leaves off the plant and munch on them. And it’s not like when dogs eat grass- they don’t get sick and vomit it out. They eat it and seem to digest it very well. They’d sit there eating it all day if we let them. They also seem to enjoy foraging for spiderwort, loquats, clover, chickweed, and goose grass! Who needs dog food?

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8 Stacie April 27, 2013 at 02:57

Just speculation, but I wonder if the “ambrosia” taxonomy speaks to ragweed as a nectar plant for bees. A late summer bloom of cascades of yellow flowers might be (or look like, to a beekeeper) a big draw as the hot summer dearth ended and some of the early fall flowers (goldenrod is a big one here in Atlanta) started to come online. Europeans brought Apis with them when they came here, and the bee’s path mirrored theirs, so early settlements of Europeans might have marveled at the flowers apparently contributing “ambrosia” to the bees who were making their sweeteners.

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9 Austin Krafft May 12, 2013 at 22:36

Ahhh Giant ragweed, mis-guided teenagers always think this yummy guy is either hemp or a cannabis specimen.

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10 Jackie May 14, 2013 at 10:37

I was worried when my goats mowed it down with their jaws. I had heard it would cause fever and boil your brain. The goats are fine I cant say the same for the ragweed crop in the yard. or shall I say that was in the yard. LOL

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11 MikeH June 4, 2013 at 00:22

Regarding Kara (post #8) and her dogs:
My basset hound loved chewing on the roots of ragweed and burdock. I never knew why, but if I got one for him he couldn’t leave it alone until it was all gone. He’d chew and eat as many as I gave him. The roots are carrot-like in appearance, and I ate small ones from our backyard raw when I was a kid.

Glad to know other dogs enjoy these things. You’re right….who needs “dog food” anyway?

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12 Johny July 17, 2013 at 11:14

i noticed that deer really like giant ragweed, but won’t touch common(minus a small nibble, maybe some medicinal benefits) they they literally took every leaf off of the big healthy plants.(as found in my garden, oh they liked the smartweed to) ;-)

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13 Liz July 21, 2013 at 16:53

Thank you for this post. I suffer from ragweed allergies, so I’m glad there’s some goodness in the plants. I heard that the leaves and blossoms of the plant can be made into a tea and lessen allergies. After several hours of research, I gathered some common ragweed near my place in WI, and put them in a dehydrator. Since the ragweed I found was very young, I got a bit of a scare when I found out that Conium maculatum (poison hemlock) grows in my area and has similar leaves, though the stem and flowers are quite different. Since the ragweed was too young to see the lack of purple conium blotches on the stem, I didn’t want to take any chances and tossed all the ragweed leaves. I just used one sprig of blossoms in a test-tea (since even a novice like me can tell ragweed blossoms from conium blossoms) I had a few test-sips, and then went back to work. However, I began to not feel well, even dizzy, so I wonder if I had an allergic reaction to even the dried ragweed tea? Has anyone heard of this happening?

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14 ulrike July 24, 2013 at 15:33

Wonderful knowledge. Thank you. Have so much ragweed on our pasture, and was wondering if we can harvest it before it blooms and goes to seed, and eat the leaves or roots, boiled, stir-fried, raw? Or just wait and eat the seeds? Raw, cooked? Thank you oh wise people of the Earth for reviving this lost knowledge. ;)

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15 Sarah September 6, 2013 at 20:54

I was also wondering if ragweed leaves could be eaten in salad, raw. Or cooked like kale?

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16 Green Deane September 7, 2013 at 08:22

No, not that I know of. If that were part of the ethnobotanical and reported use I would have mentioned it.

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17 Cyndi July 2, 2014 at 22:35

I followed directions I found on making a ragweed tincture that called for boiling the leaves. I used Giant Ragweed and was rather surprised by the super buttery smell and tried a bite. Other that having a rough texture, the boiled leaves taste amazing. I had three bites, no ill effects. Do you know of any toxicity, or is there just not much that we do know about it…other than the grain aspect?

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18 Marjie September 14, 2013 at 22:07

Really interesting article! I was looking for information on how to harvest the seeds. I am wondering if they could be added to baked goods like chia is. Thank you for sharing all your information!

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19 beverly September 26, 2013 at 07:45

can you reduce allergies by making a tea out of the leaves?

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20 Green Deane October 1, 2013 at 19:30

With apologies, I have no idea. I am not an herbalist and most certainly have no medical credentials at all.

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21 jaja October 1, 2013 at 07:24

ahh ragweed, %$&^&*%^ and $%^&^ lol , I used to always love walking in the way back woods as a kid, this plant always amazed me because it is one of the few plants with flowers on them in sept + and they are bright yellow. when I got to my teens I learned to hate it very quickly and the months that brought its bloom, lol.
I really think its a cool plant heh, and I love learning about what things can be used for survival, just never know and hard to miss this plant for sure,,, could easily gather a bucket full of the seeds quickly.

my question is, if you are allergic, will the oil from seeds still give reactions?

how many seeds would yield enough oil for say a cup to pint ect?

cool articly ,ty

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22 Ella January 29, 2014 at 00:41

Two plants that are dangerous to consume, if you are allergic to Ragweed, I have found from personal experience, are Stevia, and Milk Thistle. I almost died from an asthma attack from eating Stevia on a regular basis for several weeks, and had a severe upper respiratory reaction in the middle of winter from drinking tea with milk thistle in it. Stevia seems to be the most potent allergen for me, of all time.

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23 Joelle Morrison August 24, 2014 at 21:32

My dogs love giant ragweed leaves. They never get sick after eating them or the wild hops and hackberry leaves they are so fond of. When I take them for walks they’re constantly sniffing for these three things, and pass up everything else. I’ve often wondered if the three different plants contain similar chemicals.

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