Devil’s club (Oplopanax horridus) is a large, fiercely thorny shrub native to the rainforests of the Pacific Northwest. It belongs to the ginseng family (Araliaceae), which places it alongside some of the most celebrated medicinal plants in the world, including Asian and American ginseng. Indigenous peoples of the Pacific coast have used it for centuries to treat dozens of ailments, and modern research is beginning to explore why. The plant is as memorable for its punishing spines as for its medicinal reputation.
How to Identify Devil’s Club
Devil’s club is a perennial shrub with thick, woody stems covered in sharp, needle-like spines that break off easily in skin and are notoriously difficult to remove. The leaves are enormous, sometimes spanning a foot or more across, shaped like maple leaves, and covered with spines on their undersides. In late summer, the plant produces clusters of small bright red berries. The whole plant looks prehistoric and aggressive, and hikers in the Pacific Northwest learn quickly to give it a wide berth.
The spines are more than a nuisance. Contact with the stem can cause painful scratches and skin irritation, and there is at least one documented case of a thorn causing serious eye injury. If you encounter devil’s club in the wild, handle it with thick gloves or not at all.
Where It Grows
Devil’s club ranges from south-central Alaska down the Pacific coast through British Columbia and into southern Oregon, extending inland to Idaho and western Montana. Small, isolated populations also exist surprisingly far east, on several islands in northern Lake Superior in Michigan and Ontario. Some botanists consider populations in eastern Asia to be part of the same species.
The plant is a reliable indicator of wet ground. It thrives in shaded, poorly drained sites near springs, streams, and seepage areas, growing in acidic soils with a pH typically between 3.8 and 6.0. You’ll find it in old-growth forests under towering western redcedars and Sitka spruces, often forming dense, impenetrable thickets along creek beds. It needs rich, moist soil and does not tolerate dry or sunny conditions.
Deep Roots in Indigenous Medicine
Few North American plants have a longer or more varied medicinal history. Devil’s club has been used by people from over 38 Indigenous linguistic groups to treat upward of 34 different medical conditions. The inner bark is the most commonly used part, typically prepared as a tea (decoction or infusion) or chewed directly.
Traditional uses span an impressive range of conditions: respiratory infections like coughs and pneumonia, gastrointestinal problems including diarrhea, arthritis, fevers, colds, and diabetes. The berries and inner bark were also applied as pastes for cardiovascular complaints, including hemorrhaging. Leaves and roots were sometimes pounded and added to baths for joint pain.
Beyond physical medicine, devil’s club holds deep spiritual significance for many Pacific coast Indigenous communities. It has been used in ceremonies for spiritual cleansing, protection against supernatural harm, and by healers in a variety of ritual practices. This dual role as both medicine and sacred plant makes it one of the most culturally important species in the region.
What Modern Research Shows
Scientists have identified a complex mix of bioactive compounds in devil’s club, including polyynes (a type of fat-soluble compound also found in carrots and ginseng), saponins, lignans, sesquiterpenes, and phenylpropanoids. In total, researchers have isolated and identified at least 47 distinct compounds from the plant. Several of these, particularly the polyynes like falcarinol and falcarindiol, have shown biological activity in lab studies.
Anti-Cancer Activity
The most active area of research involves devil’s club’s potential effects against cancer cells. In laboratory studies, concentrated extracts from the root bark slowed the growth of breast cancer and lung cancer cell lines. The key finding is that the fat-soluble fractions of the plant are responsible for this effect, while the water-soluble portions actually promoted cell growth. This means a simple tea may not deliver the same anti-cancer compounds that show activity in lab extracts. Researchers found the mechanism involves triggering cancer cells to self-destruct, a process called apoptosis. These are strictly test-tube findings and have not been confirmed in human studies.
Blood Sugar and Diabetes
One of the most persistent traditional claims is that devil’s club helps manage diabetes. Several physicians over the years have reported patients with diabetes maintaining normal blood sugar while taking devil’s club preparations. However, a pilot study published in Canadian Family Physician carefully monitored blood glucose in diabetic and healthy adults drinking devil’s club tea and found no measurable blood sugar-lowering effect. The gap between traditional reports and clinical testing remains unexplained, though it’s possible that different preparations or longer use could produce different results.
Antibacterial Properties
Compounds extracted from the inner bark, particularly the polyynes, have demonstrated antibacterial activity in lab settings. This aligns with traditional use of the plant for infections, though again, human clinical trials are lacking.
How People Use It Today
The inner bark remains the most prized part of the plant. Modern preparations include tinctures (liquid extracts in alcohol), teas made from dried inner bark, and topical salves. Commercial tinctures are available from herbal supplement companies, typically sold as liquid drops to be added to water or juice and taken between meals. The root bark is harvested in spring or fall, carefully peeled away from the spiny outer layer, and dried for later use.
Because devil’s club is a wild-harvested plant rather than a cultivated crop, supply depends entirely on healthy wild populations. This makes sustainable harvesting practices important, especially given the plant’s slow growth and very specific habitat requirements.
Safety Considerations
No cases of significant toxicity from devil’s club have been documented, but that doesn’t mean it’s without risk. The plant has traditional use as both an emetic (to induce vomiting) and a purgative (to stimulate bowel movements), which suggests it can cause gastrointestinal distress at higher doses. No interactions with pharmaceutical drugs have been confirmed, though anyone taking diabetes medication should be cautious given the plant’s traditional use for blood sugar, even though clinical studies haven’t confirmed that effect. There are no safety studies in pregnant or breastfeeding women.
Conservation Concerns
Devil’s club depends on mature, wet old-growth forest, and that habitat is shrinking. In British Columbia, the ecological communities that support devil’s club have declined by an estimated 10 to 30 percent in recent decades, primarily due to logging. Forest harvesting has affected roughly 22 percent of the mapped area where these plant communities exist. The species is considered highly vulnerable because full recovery of the old-growth forest structure it depends on takes 160 to 200 years after logging, and many associated plant species remain absent even 80 years later.
This slow recovery timeline means that once a devil’s club habitat is logged, it effectively disappears for multiple human generations. For anyone interested in using or harvesting the plant, sourcing it responsibly and supporting habitat conservation is essential to keeping wild populations viable.