How experts tell deadly plants from their edible look-alikes

Key takeaways

• In 2024, U.S. poison centers logged 28,770 plant exposures in children 5 and under, making plants the 10th most common category in that age group¹.
• A piece of water hemlock root just 2 to 3 centimeters long can kill an adult, and the plant can pass for parsnip².
• In a test of 17 toxic plant species, the best phone app named 10 correctly and the worst named just 1⁹.
• Experts confirm a plant by checking several features together and treat any leftover doubt as a reason not to eat it³¹⁰.
• If someone eats a plant you can’t name, call Poison Control at 1-800-222-1222, or 911 if the person has a seizure, collapses or struggles to breathe¹⁴.

On October 5, 1992, two brothers walked into the woods of midcoastal Maine to hunt for wild ginseng². The younger brother, 23, pulled up a plant growing in a swampy spot and took three bites of its root. His 39-year-old brother took one².

Within 30 minutes, the younger man was vomiting and having seizures. He died roughly three hours after eating. His brother also had seizures but survived².

The root was water hemlock (Cicuta maculata). The CDC’s report on the case called it “the most toxic indigenous plant in North America”².

The brothers were doing something many people who love natural health value: gathering food and medicine from the land. Their error wasn’t a lack of respect for nature. It was trusting a quick look.

This guide shows how the worst mix-ups happen, why an app can’t save you, and how botanists confirm what a plant is.

Plants are a common poison call, and the deadliest look like food

In 2024, U.S. poison centers recorded 28,770 plant exposures in children 5 and under, out of more than 2 million human exposures of all kinds and all ages¹. Plants ranked 10th among the substances involved in young children’s cases¹.

The Oregon Poison Center alone handles more than 500 plant cases a year, according to a 2023 lecture by its medical director, Rob Hendrickson⁵. To work out which plant a caller is holding, the center leans on botanists and master gardeners⁵.

The rare deaths follow a different pattern. From 1979 through 1988, at least 58 people in the United States died after eating a poisonous plant that had been mistaken for an edible fruit or vegetable². At least five of those deaths involved water hemlock².

In other words, the plants that kill are often the ones that look like dinner.

Five deadly doubles, and the clues that give them away

The hemlocks and the carrot family

Water hemlock belongs to the same plant family as carrots, parsnips, celery and parsley². To the eye, it can pass for a parsnip. The CDC adds that it gives off a fresh-turnip smell and has a sweet taste, which explains folk names such as “false parsley” and “poison parsnip”².

Its root holds the most poison, and the plant is toxic at every stage of growth. There is no antidote, so doctors can only give supportive care².

Poison hemlock (Conium maculatum) is a different plant with a similar problem. Its white flower clusters are hard to tell from those of wild carrot, also called Queen Anne’s lace³.

Hannah Wright-Smith, a weed specialist with the University of Arkansas extension service, tells readers to check the stems. Wild carrot keeps its hairs from seedling to seed. Newer poison hemlock stems lack hairs, feel waxy and turn purple or purple-flecked³. Hemlock acts fast: poisoning symptoms usually begin within a few minutes³.

Her guide also retires a popular shortcut. Many foragers look for a dark dot at the heart of a Queen Anne’s lace flower, but it isn’t always there, so it proves nothing³. When you can’t be certain, the guide says, play it safe³. For a forager, that means leaving the plant where it grows.

Foxglove posing as comfrey

In Taiwan, a neighbor picked leaves in a national park, believing they were comfrey, a traditional healing herb. The leaves were brewed into a tea meant to protect the liver⁴.

Nine people drank it. The plant was foxglove (Digitalis purpurea), whose cardiac glycosides are chemical cousins of the heart drug digoxin⁴⁵. All nine had digoxin blood readings far above normal. The highest was 139.5 nanograms per milliliter, more than 100 times the top of the normal range⁴.

Three patients needed temporary pacemakers. All nine recovered⁴.

The doctors who reported the outbreak noted that comfrey and foxglove leaves look alike when the plants aren’t in bloom, though their flowers are very different⁴. Oregon’s poison center lists borage as another plant that foxglove gets mistaken for⁵.

Lily of the valley and autumn crocus posing as wild garlic

Across Europe, foragers prize wild garlic (Allium ursinum), a spring green of shady forests⁶. Its young leaves have two dangerous twins. Germany’s Federal Institute for Risk Assessment (BfR) names autumn crocus, which it rates as very poisonous, and the poisonous lily of the valley⁶. The agency says these mix-ups lead to poisonings every season, some of them fatal⁷.

Autumn crocus can fool people twice. Severe stomach and bowel symptoms start 6 to 12 hours after eating. Then comes a quieter spell of one to three days before organs can begin to fail⁷.

In North America, Oregon’s poison center flags a related mistake with ramps (Allium tricoccum), a wild green foraged in Appalachia. Ramps have purplish stems and smell of garlic. Lily of the valley shows two oval leaves and small white flowers, and it contains cardiac glycosides, the same class of heart-affecting compounds found in foxglove⁵.

Death camas beside wild onion

In his 2023 lecture, Oregon’s poison center director showed death camas (Toxicoscordion venenosum) side by side with two edible plants, wild onion and common camas⁵. The slides offer no quick field test for telling them apart⁵. That gap is the lesson: wild bulbs call for an expert.

A sniff test has its own trap. The BfR found it with wild garlic: if your fingers still smell of garlic from a leaf you crushed earlier, a toxic leaf can seem to pass⁶.

Jimsonweed in the family stew

In July 2008, a Maryland cook made a potato stew with mint and leaves from an unknown plant that “grew wild in the yard”⁸. Six family members, ages 38 to 80, ended up in the emergency department with confusion, racing hearts and enlarged pupils. Five needed intensive care⁸.

The unknown plant was jimsonweed (Datura stramonium), which contains atropine and scopolamine. A horticulture expert found freshly cut jimsonweed in the yard and more in the kitchen trash. Cooking doesn’t substantially reduce the poison in the leaves⁸. Everyone recovered⁸.

A look-alike table to keep with your field guide

This table gathers the doubles above. The last column is the point where a careful forager walks away.

Plant you want	Dangerous double	How to tell them apart	When not to risk it
Wild carrot (Queen Anne’s lace)	Poison hemlock	Wild carrot stems are hairy; hemlock stems are smooth, waxy and often purple-spotted3	Any doubt at all; the flowers alone can’t settle it3
Wild parsnip or other wild “carrot” roots	Water hemlock	Looks like parsnip, smells like turnip; the fatal Maine root came from a swampy spot2	Never taste-test a wild root; a 2 to 3 cm piece can kill2
Comfrey or borage leaves	Foxglove	Leaves look alike before bloom; flowers differ sharply45	Leaves picked from a plant that isn’t flowering4
Wild garlic or ramps	Lily of the valley, autumn crocus	Wild garlic leaves smell of garlic when rubbed; ramps have purplish stems56	No garlic smell, or hands already smelling of garlic or leek6
Wild onion or common camas	Death camas	A poison center pairs them; no quick field test is given5	Wild bulbs without an expert beside you5
An unnamed yard plant	Jimsonweed	Cooking doesn’t weaken its leaves8	Any plant you can’t name, in any dish8

Phone apps make a decent first guess and a poor final answer

Plant apps are quick and easy. Toxic plants are a hard test for them.

In a 2021 study in the Journal of Medical Toxicology, researchers photographed 17 common toxic plant species, at least 10 plants of each, and ran the pictures through three iPhone apps⁹. PictureThis correctly named 10 of the 17 species. Pl@ntNet named 8. PlantSnap named just 1⁹.

A 2024 study at the Queensland Poisons Information Centre in Australia used real cases. Six researchers ran photos from 25 suspected plant poisonings through six apps¹⁰. The best apps matched the botanist’s answer about three-quarters of the time: 74% for PictureThis and 72% for Pl@ntNet and Plant Identifier. PlantSnap managed 38%¹⁰.

Different researchers using the same app sometimes got different answers. And the authors concluded the apps weren’t reliable enough to guide poison advice, calling a botanist’s identification the gold standard¹⁰.

Treat an app like a hint from a stranger: a name to look up, never proof that a plant is safe to eat.

How botanists confirm what a plant is

Experts rarely trust one feature; the Arkansas guide calls for more than one trait³. A careful identification looks at the whole plant: root, stem, leaves, flowers, fruit, smell, habitat and season.

Botanists often work through a dichotomous key. That is a printed or digital series of paired choices, such as “stem hairy” or “stem smooth.” Each answer sends you to the next pair until one name is left. Because it forces you to check one feature at a time, it slows down the snap judgment that fools people.

Botanists also rely on vouchers. A voucher is a pressed, labeled sample of a plant stored in a herbarium, a library of dried plants, so anyone can recheck the identification years later.

Local experts are the next layer. Poison centers call on botanists and master gardeners⁵. In the Maryland stew case, a horticulture expert solved the mystery by searching the yard⁸.

When plant material is dried, chopped or powdered, the leaf shape and flowers are gone. Then labs turn to microscopes, chemical fingerprinting (chromatography, which separates a sample’s compounds) and DNA tests. In 2015, the president of the American Herbal Products Association, an industry trade group, said DNA identifications should be confirmed with methods like chromatography or microscopy¹².

The wrong plant can arrive in a box, too

Misidentification isn’t only a foraging problem. On September 10, 2003, the FDA advised consumers not to drink teas brewed from star anise, the trade journal SupplySide reported the next day¹¹.

About 40 people had fallen ill over the previous two years, including 15 infants. Symptoms ranged from seizures and vomiting to jitteriness, and all recovered. A resident physician at Miami Children’s Hospital had uncovered the pattern after treating a baby with seizures who had been given star anise tea, a folk remedy for colic¹¹.

The concern was Japanese star anise (Illicium anisatum), a toxic plant meant only for decoration. Chinese star anise (Illicium verum), the familiar spice, is considered safe as a food. Once dried, the two look alike, so the FDA was weighing chemical tests to tell them apart¹¹.

Our article on traditional knowledge tells a better-known story, in which a toxic Aristolochia herb ended up in place of the plant named on a label.

DNA tests can catch a swap, but they can’t read every bottle

In February 2015, New York Attorney General Eric Schneiderman sent cease-and-desist letters to GNC, Target, Walmart and Walgreens, the trade outlet NutraIngredients reported¹². According to that report, DNA tests run for his office found that 79% of the herbal supplements tested lacked DNA from the labeled herb or contained unlisted plants¹².

The test, DNA barcoding, reads a short, standard stretch of genetic code and matches it against a reference library. The attorney general’s office said the tests turned up rice, beans, pine, citrus, asparagus, primrose, wheat, a houseplant and wild carrot¹².

Scientists and industry groups pushed back hard. Critics said many of the products were probably extracts, and processing can leave DNA too broken to read¹²¹³. So a missing DNA signal doesn’t prove the herb is missing.

Barcoding also shows what is present, not how much¹². And the attorney general’s office declined to publish its test data¹³.

By May 2015, the two sides had found some middle ground. In a joint statement, the attorney general and the Natural Products Association, an industry group, agreed that no one test can give consumers full confidence. They placed DNA barcoding before extraction, when the raw plant is checked¹³.

For shoppers, the useful question is simple: how did the company confirm the identity of the raw herb before it was processed?

Five rules before you harvest anything

Respect for plants runs deep in natural health, and in many family and Indigenous traditions it means knowing a plant through years of seasons, not through one glance. These rules put that respect into practice.

1. Learn the poisonous plants first. The CDC urges foragers to know the dangerous plants that grow in their own area². Learn the deadly double before you learn the edible.
2. Match several features, not one. Check stems, leaves, roots, smell and habitat together³. When you can, wait for flowers, which separate some doubles, like foxglove and comfrey, far better than leaves⁴.
3. Distrust any single shortcut. A purple dot, a smell test or an app result can each mislead³⁶¹⁰.
4. Get a human second opinion. Ask an experienced local forager, botanist, master gardener or extension office before eating a new plant⁵¹⁰.
5. When in doubt, leave it. Never nibble an unknown root to test it; the Maine brother took three bites². Buy wild garlic and similar greens from a trusted grower, or grow your own⁶.

What the evidence shows

Claim	Evidence rating	What the research shows
Look-alike mix-ups cause serious and fatal poisonings	Strong evidence	CDC reports and published outbreaks248
A phone app can confirm a toxic plant on its own	Evidence says no, or unsafe	The best apps missed 7 of 17 toxic species in one test and about a quarter of real cases in another; a botanist remains the standard910
A rub-and-sniff test alone confirms wild garlic	Not enough evidence	A useful screen, but lingering scents can fool it6
DNA barcoding works on finished herbal extracts	Evidence says no, or unsafe	Processed DNA is often too damaged; testing belongs before extraction13
Cooking makes a poisonous plant safe	Evidence says no, or unsafe	Cooking didn’t neutralize jimsonweed leaves8

Questions readers ask

The bottom line

Nature makes both food and poison, and a few of its most dangerous plants look like the food. Water hemlock, foxglove, lily of the valley, autumn crocus and jimsonweed have all ended up in meals and teas because someone trusted one feature, one smell or one guess.

Experts slow down. They check many features, use keys and vouchers, ask other experts and leave a plant alone when doubt remains. Apps and DNA tests can help, but neither replaces that care. When someone has already eaten a plant you can’t name, call Poison Control first and identify the plant second.

Related reading

• Nature makes both medicine and deadly poison, and respecting it means telling them apart
• An ancient recipe led to a Nobel prize, and new treaties ask who benefits
• What gets into supplements that isn’t on the label
• Herbal supplements are a $13 billion business, and herbalists need no license
• Only Panax can be called ginseng on U.S. labels, and this is how to decode the rest

Sources

1. Poison Control, National Capital Poison Center. “National Poison Center Statistics, 2024” (from the 2024 Annual Report of the National Poison Data System, America’s Poison Centers; Beuhler MC et al., Clinical Toxicology, 2025). Accessed October 2026. poison.org
2. Centers for Disease Control and Prevention. “Water Hemlock Poisoning—Maine, 1992.” Morbidity and Mortality Weekly Report, 1994;43(13). cdc.gov
3. Wright-Smith H. “Poison Hemlock Identification and Control” (FSA2203). University of Arkansas System Division of Agriculture Cooperative Extension Service (publication code dated 2023). uaex.uada.edu
4. Lin C-C, Yang C-C, Phua D-H, Deng J-F, Lu L-H. “An Outbreak of Foxglove Leaf Poisoning.” Journal of the Chinese Medical Association, 2010;73(2):97–100. wd.vghtpe.gov.tw
5. Hendrickson R. “Plants” (lecture slides, Oregon Poison Center, Oregon Health & Science University). 2023. ohsu.edu
6. German Federal Institute for Risk Assessment (BfR). “Odour Test With Pitfalls: What to Look Out for When Collecting Wild Garlic.” Press release 9/2025, March 21, 2025. bfr.bund.de
7. German Federal Institute for Risk Assessment (BfR). “Wild Garlic: Confusion Often Leads to Poisoning.” Press release, April 5, 2023. bfr.bund.de
8. Centers for Disease Control and Prevention. “Jimsonweed Poisoning Associated With a Homemade Stew—Maryland, 2008.” Morbidity and Mortality Weekly Report, 2010;59(4). cdc.gov
9. Otter J, Mayer S, Tomaszewski CA. “Swipe Right: A Comparison of Accuracy of Plant Identification Apps for Toxic Plants.” Journal of Medical Toxicology, 2021;17:42–47. dx.doi.org
10. McNeill I, Knoeckel R, Goggin A, Wylie C, Isoardi K. “Accuracy of Plant Identification Applications to Identify Plants in Suspected Poisoning Cases Referred to the Queensland Poisons Information Centre.” Toxicology Communications, 2024;8(1) (DOAJ record). doi.org
11. SupplySide Supplement Journal. “FDA Issues Star Anise Tea Advisory.” September 11, 2003. supplysidesj.com
12. NutraIngredients. “NY AG Takes On GNC, Walgreens, Walmart, Target on Herbal Supplements.” February 3, 2015. nutraingredients.com
13. NutraIngredients. “The NY AG’s Herbal Probe So Far: From GNC to Devil’s Claw.” September 11, 2015. nutraingredients.com
14. America’s Poison Centers. “Poison Help” (official site; 1-800-222-1222). Accessed October 2026. poisonhelp.org