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Five Traditional Plant Medicines and How They Might Work

Mule deer in yerba mansa
Mule deer in yerba mansa | Photo: J.N. Stuart, some rights reserved

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This article includes discussion of Native Californian peoples' traditional use of plants as medicine. It is intended for cultural and environmental education purposes only, and should not be taken as medical advice.

Native people in California relied on whatever living things grew around them for food, fiber, for clothing and shelter. Their approach to medicine was no different. Based on millennia of experience and experimentation, knowledge handed down generation by generation woven seamlessly into culture, Native people had a pharmacopeia for many common illnesses and injuries in the form of the plants, animals, and fungi with which they shared the landscape.

In many cases, modern scientists have found biological and chemical properties inside these medicinal plants that may well account for the healing properties ascribed to them by Native healers. The canonical example is aspirin, acetylsalicylic acid, originally derived from compounds found in willow bark. But other examples abound, from the eucalyptol in white sage (a topical anaesthetic used in many over-the-counter cough and cold medicines) to the ephedrine and related compounds found in joint-fir (Ephedra species).  

Let’s take a look at five different plants used by a number of California Native peoples. One is benign enough to be used for pleasure, another so dangerous you probably shouldn’t touch it, and the other three somewhere in between.

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One of the overall differences between traditional Native medical practices and Western medicine is that practitioners of Traditional medicine often don’t see their discipline as distinct from other parts of their culture, from cooking to music to architecture to literature. Pulling an individual plant out of that context, as Western science often does, and then analyzing that plant’s biochemistry and pulling out individual substances to test for pharmacological activity, is a very different way to learn about how a plant works. We’ve learned a lot about plants that way. But we run the risk of missing the point when we analyze plants rather than placing them in context.

We also run the risk of appropriating hard-won knowledge for our own profit. When pharmaceutical companies, for example, examine the constituents of traditional medicines, whether from the rainforest or the tundra, and synthesize analogous chemicals for use as drugs, they profit from the hard-won, long-preserved knowledge of the traditional peoples who discovered those plants’ properties.

With all that said, the five plants covered here have been extensively studied, so discussing them won’t likely contribute to further appropriation. So at the risk of missing the larger cultural point by talking about plant chemistry, let’s dive in.

Yerba Mansa (Anemopsis californica)

An attractive plant that grows in wet soil throughout the southern two thirds of California, yerba mansa is found along seeps and wet places elsewhere in the Southwest as well, from Texas to Baja California. When in flower, it’s hard to mistake yerba mansa for anything else: its striking white, sunflower-like blooms are held four or five inches above a spreading mat of flat, gray-green leaves with a waxy coating.

Yerba mansa was and is held in high regard by many Native peoples in California and elsewhere. Mexican curanderos regard the plant as something like a cure-all; Spanish settlers in present-day  Mexico and Texas adopted its use from local Native people as early as the 17th Century.

California Native peoples from the coastal Chumash to the desert Shoshone have used yerba mansa as an anaesthetic and antiseptic for a very long time. Its dried roots, ground into a powder, are used to relieve sore throats in much the same way as the eastern North American plant goldenseal. As wild goldenseal is endangered due to overharvesting, some have suggested that yerba mansa, which is easily cultivated, might offer a more ecologically benign herbal throat medicine.

The leaves also play a role in traditional herbal medicine, with an infusion often used externally on small wounds as an antiseptic. An infusion of the roots is more widely used. The first person who thought of using yerba mansa as a medicine was likely following her nose: the roots have a strong smell containing notes of camphor and eucalyptus.

Among the chemical constituents found in yerba mansa is methyl eugenol, commonly used to impart a clove-like flavor to processed foods. Methyl eugenol acts as an antispasmodic and anaesthetic, which likely explains at least some of yerba mansa’s persistent popularity as an herbal medicine.

A note of caution, however: methyl eugenol is a known mutagen, and a likely carcinogen in humans.

Creosote (Larrea tridentata)

Here’s another medicinal plant that is both widely used and worthy of some caution. Creosote, often called “chaparral” by herbalists, is likely the most common woody plant in the Mojave and Sonoran deserts. In many places in the hot desert lowlands, especially in summer when the spring annuals have died back, creosote might be the only vascular plant growing for hundreds of feet in any direction.

Sniff creosote leaves on one of those hot summer days and you won’t be surprised that people have thought to use it as a plant medicine. The leaves’ pungent resinous smell has contributed to at least one common name for the plant, the Spanish “hediondilla” or “little stinker.”

Peoples throughout the deserts used creosote leaves, both externally and internally, for a range of complaints. The Paiutes used (and still use) creosote leaf tea to treat colds, gastrointestinal complaints and skin conditions. Shoshone people used the tea as a diuretic as well. A range of different peoples record using the leaves as a poultice for sore muscles and minor wounds, and bathing in an infusion of creosote was also used to relieve menstrual discomfort. A number of different preparations of the leaves, from a fresh paste to powder to plasters, were used as topical disinfectants for wounds and sores. Today, creosote is still widely used among Native and non-Native people alike — though not as widely sold in herb stores.

The reason that creosote (a.k.a. “chaparral”) came off shelves is likely the same reason Native peoples used it for various ailments: nordihydroguaiaretic acid (NDGA), a highly reactive antioxidant. NDGA isn’t the only antioxidant in creosote leaves: more than 20 flavonoids occur in the chemical cocktail generated by creosote leaves. But if you were to extract all the antioxidants in creosote leaves and weigh them, NDGA would make up about 40 percent of the total.

NDGA has been examined and tested abundantly in the laboratory, and found to possess a range of properties that offer promise in treatment of various modern-day illnesses.  It is the subject of continuing study by cancer researchers, who have found that high concentrations of NDGE can inhibit anaerobic respiration in cancer cells, slowing or reversing tumor growth. The problem is that high concentrations of NDGA may also cause liver and kidney problems, especially in people with pre-existing weaknesses in those organs. Some studies have shown that lower doses of NDGA actually promote growth of existing tumors, while others suggest that the chemical may inhibit cells from becoming cancerous in the first place, so the scientists are still examining the chemical.

A number of the other flavonoids in creosote’s chemical cocktail have been found to act as antibacterials or antimicrobials. Four of those flavonoids, of a type called 3-methoxyflavones,  can keep viruses such as the polio virus and rhinoviruses from duplicating themselves in host cells, making them potentially effective antiviral drugs. There are eight other methoxyflavones in creosote leaves that may have similar properties.

Several cases of creosote toxicity have been recorded since the plant was touted as a cancer cure in the late 1980s, some resulting in serious long-term injury to the liver and other organs. It’s been suggested that these incidents mainly stem from people consuming large amounts of the powdered leaves internally, a practice that was and is uncommon to nonexistent among traditional Native users of the plant. Nonetheless, the FDA removed NDGA from its “Generally Recognized As Safe” list of food additives in 1970 due to concerns over its toxicity in rats, and issued a 1992 warning on the use of dried creosote leaves. (The FDA admitted that some of the illnesses may have been caused by mislabeling of other materials as “chaparral.”)

death camas blossoms
Death camas in bloom | Photo: Chris Clarke

Death camas (Toxicoscordium)

Go back up to the top of this article and re-read the disclaimer. Then take a second look at the name in bold at the head of this entry. Then consider that the several species of death camas in California now bear the Latin name Toxicoscordium. (Many people know it by its older name Zigadenus.)Then further consider the southern Pomo name for this plant, “tsim' bu,” “harmful bulb,” just one example of dozens of cautionary names in Native languages for the death camas.

What do all these pieces of information convey to us? A simple warning: Do not ingest death camas under any circumstances. Consumption of a fairly small amount of death camas can cause blood pressure crashes, cardiac arrhythmia, loss of muscle control, paralysis, and the suite of poisoning symptoms for which toxicologists use the mnemonic acronym “SLUDGE”: Salivation, Lacrimation (Tears), Urination, Defecation, GI upset, and Emesis (vomiting). And then there's the side effect mentioned on the label: death. Prompt medical attention can often facilitate a complete recovery from everything but that last-mentioned effect, but it still hardly seems worth it.

Most people who consume death camas do so after mistaking the bulbs for other, less deadly edible underground plant parts, but all parts of the plant are poisonous. It’s thus completely unsurprising that death camas would attract the attention of the first Traditional Ecological Knowledge researchers thousands of years ago. When a plant is that poisonous, that means something is going on inside that plant that is very powerful, and power can often be used for good as well as ill.

So it’s equally unsurprising that traditional Native healers had a couple very cautious uses for death camas, mainly applying the bulbs externally to bruises and sprains for pain control. Some people mashed the bulbs fresh and applied them for up to 12 hours; others roasted the bulbs first.

As it turns out, the same active ingredients that make death camas so dangerous may account for the plant’s use as a topical analgesic and antispasmodic. All parts of the death camas contain neurotoxic alkaloids, the most common being the steroidal alkaloid zygacine.

Zygacine and its close cousins in death camas plants interfere with the transport of sodium across cell membranes by physically blocking the channels through which cell membranes actively transport sodium ions into the cell. That’s a problem, because active transport of sodium ions across cell membranes is absolutely necessary for transmitting signals through nerve cells, as well as for muscle cells to know when to contract and relax.

By interfering with that signaling, zygacine can cause nervous system failure, muscular paralysis, and — understandably, considering that the heart is just another muscle — cardiac arrest.

But sometimes you want nerves to stop signaling quite so much, and you want muscles to ignore nerve signals telling them to contract. Painkillers work — to oversimplify — by making nerves shut up for a minute. Muscle relaxants work by making muscles ignore the nerve signals telling them to contract for no reason. If applying a poultice of death camas to a bruised and spasming muscle allowed a little bit of zygacine to enter the skin at the affected area, it may well have functioned as an effective analgesic and antispasmodic. Roasting the bulbs may have reduced their potency for greater safety, or created breakdown products of zygacine or related alkaloids.

And again: we have safer alternatives, including the aspirin chemists derived from willow bark a century ago. Death camas is now best used as a nice flower to look at in a spring meadow. But its historical use is a good reminder of the resourcefulness and deep familiarity with living things found in many Traditional Ecological Knowledge practices.

Douglas fir cones
Douglas fir needles and cones | Photo: Dan Mullen, some rights reserved

Douglas fir (Pseudotsuga menziesii)

The Douglas fir is probably the safest traditional plant medicine on this list: safe, that is, unless a big one falls on you. Growing from northern California northward to British Columbia, the Doug fir is one of the most common and easily recognizable conifers along the Pacific coast. (The closely related bigcone Douglas fir, Pseudotsuga macrocarpa, grows in southern California mountains and is similar enough that it might as well be lumped in with its cousin for purposes of this discussion.)

Douglas fir was and is used in a number of different ways in Native traditional medical practice, from using the resinous sap as a salve to bathing in the smoky steam from fresh leafy branches placed on a fire. The use that persists today with the most popularity is drinking a tea made from the most recent spring growth of needles and small twigs.

The tea is pleasant tasting, surprisingly lemony with a complex and subtle bouquet of other citrus, pine and camphor. Essential oils and terpenes are the reason for the flavor. Douglas fir twigs and leaves contain a complex cocktail of these chemicals with imposing names, with alpha- and beta-pinene, sabinene, delta-3-carene, terpinolene, and limonene making up four fifths of the total.

The pinenes in Douglas fir have been found to possess antiseptic and antifungal properties, and have been used as expectorants and bronchodilators. Limonene is reputed to help with mild stomach problems, and the camphoraceous aroma of Douglas fir tea certainly has opened its share of mildly stuffed sinuses.

Douglas fir tea also contains significant amounts of vitamin C, and the precursor chemicals for vitamin A. These may not seem particularly medicinal; they’re necessary nutrients rather than drugs. But when you recall that most of human history has been conducted without convenience stores close at hand, and people depended on seasonally available food for all their vitamins and minerals, the medical importance of Vitamin C in particular becomes clearer. Dietary sources of Vitamin C are mainly fruits and leafy green vegetables, both of which can be in short supply in winter, and potatoes, which were not available in pre-contact California so far as we know.

A deficiency in Vitamin C can lead to scurvy, an unpleasant disease that is fatal if untreated. People with scurvy respond rapidly to taking Vitamin C, improving substantially in just a few days and often recovering completely within a month or so. Which would make Douglas fir tea, available year round, a very important medicine when the stored fruit supply ran low.

Elderberries
Elderberries | Photo: David O, some rights reserved

Blue elderberry (Sambucus nigra)

This rangy shrub is everywhere in California: it even grows in a few places in the hot deserts in the southeastern part of the state. It grows in a lot of other places, too: the species grows throughout North America and Europe. Sambucus nigra is diverse enough in appearance that botanists have often divided it into a few smaller species: many California native plant fans will have learned the local blue elderberry as Sambucus mexicana, or by other names still.

In California, the subspecies Sambucus nigra caerulea is an attractive, towering shrub with clusters of white flowers in spring and waxy-looking blue berries in summer. When ripe, flowers and the ripe berries are the only edible parts of this plant, and some sources recommend cooking the berries just to be on the safe side, as a few cases of mild gastrointestinal distress have been reported from eating raw ripe berries. All other parts of the plant are toxic: they contain alkaloids like sambucine, a strong purgative and emetic, and hydrocyanic acid, which the body converts to cyanide and which is thus dangerous if consumed in large amounts. (Think peach pits: one doesn’t have enough hydrocyanic acid to kill you, but a few might.)

That sambucine contributed to Native use of elder bark in small doses as a laxative, and in larger doses as an emetic. Leaves were used this way as well: The Ohlone peoples in the East San Francisco Bay area made a tea of the leaves for internal consumption as a purgative. The flowers, often prepared as a tea, have been used to induce sweating and clear congested sinuses, as well as in antiinflammatory and diuretic roles.  

But it’s the berries that saw the plant’s widest use as a medicine, partially because of their flavor when cooked and partially due to their safety compared to other parts of the elderberry plant. That’s not just true for Native peoples in California: people across the plant’s range from Oregon to Austria have used the berries for medicinal purposes, as a tonic, a mild laxative (when raw), to treat scurvy, and as a general tonic.

Elderberries’ nutritive value is impressive: they’re good sources of Vitamins C and B6, a great source of Vitamin A (with 10 times the Vitamin A of cranberries, grapes, and blueberries; 20 times that of raspberries; and 50 times as much Vitamin A as strawberries) as well as healthy doses of iron, phosphorus, and just plain old calories.

So from a medical standpoint, elderberries were clearly well-suited to helping fix nutritional deficiencies. But the fruit also contains other constituents that may be more strictly pharmaceutical in their effects. In particular, elderberries contain a large amount of a class of chemicals called anthocyanins, plant pigments in the chemical group known as flavonoids that act as antioxidants. The two most abundant anthocyanins in elderberry fruit, with the imposing names cyanidin 3-glucoside and cyanidin 3-sambubioside, are powerful antioxidants that seem to be more stable in storage than antioxidants found in other fruit.

Watch Tending the Wild: Gathering Medicine

The role antioxidants play in human health is a matter of some disagreement, especially since agricultural interests seized on the term as a healthy-seeming marketing tool. But it’s pretty well established that some antioxidants play a critical role in human health. Oxygen-rich compounds such as hydrogen peroxide, hypochlorous acid and hydroxyl ions are generated when oxygen interacts with other compounds in the cell. These reactive substances can cause chemical chain-reactions that result in damage to important parts of the cell such as DNA molecules — which can then lead to bigger problems like cancer and degenerative diseases. Antioxidants are used in living cells to block these chain reactions, limiting the amount of damage.

There have been a lot of claims made that nutritional antioxidants — the kind you get from eating instead of having your body make them on its own — can help slow or even reverse the onset of diseases like Parkinson’s, Alzheimer’s, and even normal aging. Those ideas have not been proven to most medical researchers’ satisfaction.

But no one disputes that nutritional antioxidants are very important in limiting damage caused by oxidation, and that that kind of damage is linked to ailments from atherosclerosis to cancer. So while it may not be true that eating antioxidants like elderberry anthocyanins  will cure whatever disease you’ve got, it may help you keep from getting it in the first place.

In other areas, Israeli virologist Madeline Mumcuoglu reported a couple decades ago that constituents in elderberry extract disabled hemagglutinin spikes — protein formations — on the outside of some viruses. That reduced the viruses’ ability to penetrate cell walls and replicate themselves, which inhibited the viruses’ ability to spread. She has since claimed success in treating influenza with elderberry extract, saying that test subjects who received the extract got well about four days sooner than a group that received a placebo. Other researchers have reported that a commercially available elderberry extract can stimulate immune system response, which could conceivably be helpful in fighting certain diseases, and possibly make things worse for allergies or autoimmune disorders where the immune system is already working too well.

Not bad for something that tastes good enough that you could put it on your pancakes.

Banner: a patch of yerba mansa in bloom. Photo: J.N. Stuart, some rights reserved

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Co-produced by KCETLink and the Autry Museum of the American West, the Tending the Wild series is presented in association with the Autry's groundbreaking California Continued exhibition. 

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