How to Differentiate Spotted waterhemlock from its Cousins.

•   Its stalks are smooth and hairless and grow to 8’. In the eastern U.S. stalks have spots or streaks, but in the western U.S. they don’t.

•   Like Poison hemlock, Spotted waterhemlock's flower umbels splay more wildly than those of Queen Anne’s lace.

•   Spotted waterhemlock has longer, broader less “compounded” or divided, less ferny-looking leaflets than Poison hemlock and other cousins.

•   Perennial roots grow short and stout. Plants over 2 years old will have clusters of thick pointed roots crowded together that resemble the tubers of a Dahlia. Roots contain many horizontal chambers and exude yellow poisonous oil when broken open. Roots of Spotted waterhemlock smell like Carrots or Parsnips and may tempt the unwary into taking a bite.

•   Since plants grow in water, the roots pop out quickly when pulled.

Left: Queen Anne’s lace tidy flowerhead and broad nest-like seedhead Right: Spotted waterhemlock’s splayed flowerheads and tighter, greenish, smaller, cylindrical seedheads in knots

It grows in moist, anaerobic, airless soil with poor drainage, low calcium, phosphorous, and humus, and it flourishes even with its roots under water. Drain the wetland to add air, add organic materials and encourage competing plants to grow. Or better yet, remove it from any area where children or favorite animals seem likely to go. Then bag and throw away all plant parts.

NO ANTIDOTE: for cicutoxin poisoning works, BUT you can prevent seizures by using barbiturates, and can keep respiration from failing by mechanical intervention. If ingested, a saline cathartic, gastric lavage (stomach pumping), or activated charcoal may help.

Other Similar-looking Weeds in the
Parsley Family may also Poison

Phytotoxic Giant hogweed, Heracleum mantegazzianum, can cause skin burns similar to those caused by a cigarette lighter applied to human skin. It grows up to 16’ in height, much taller than other Parsley, Umbelliferae, family members; has huge leaves, up to 3 ½’ long; broader flower heads to 20” wide that can produce 20,000 seeds per plant; and purple splotches on stems like some of its lethal cousins. It shares its hairy legs with Queen Anne’s lace. In an episode of the BBC’s garden/mystery series Rosemary and Thyme, the two gardening sleuths discovered that Giant hogweed had, suspiciously, been cut down on the property and was otherwise being encouraged to grow as if for harvesting. Upon investigation, Rosemary Boxer and Laura Thyme detected that a notorious poisoner, disguised as the housekeeper, was putting its extracts in a skin salve to slowly destroy her wealthy son-in-law. (no photos)

Another family member, Fool’s parsley, Aethusa cynapium, appears to cause vision problems and nausea in those who consume it. The most acute nausea occurs if the forager drinks milk after eating it. Yet, some herbalists use it homeopathically. It’s less toxic than some of its look-alike cousins, but still worthy of avoidance. Like others in its family, its flowers attract pollinators or can self-pollinate. It lacks hairy legs (stalks). Its flowerheads spread a modest 2” wide, with distinctive long “bracteoles”, or swirling skinny leaf-like bracts that form under flowerheads. (no photos here.)

Two Composite Family Poisoners

White snakeroot, Eupatorium rugosum has composite flowers in “open corymbs”, an open flat-topped umbrella-like structure, that to my naked eyes resembles the shape of the umbels of the Umbelliferae above. But it is a Composite or Asteraceae family member. It grows to 6’ tall on shallow fibrous roots and has 3-6” long large leaves on long sub-stalks. Leaves are simple, heart-shaped or oval, with serrated edges. Its leaves are neither compound nor ferny like the leaves of the Umbelliferae. This famous toxic weed caused milk-sickness and death in Abraham Lincoln’s mother, Nancy Hanks Lincoln. Cows and horses that eat enough of it, cumulatively, get the “trembles”, or muscle tremors. Folks who drink lots of the milk of afflicted cows get weak, vomit, have garlicky breath, muscle tremors, delirium, then, often, die. Its toxin, tremetol, is strongest when the plant is green and remains active even after it dies. (no photos4)

In the early 1830s Anna Bixby, a woman doctor, which in male-dominated early America was cause for skepticism, connected the dots about the season of the disease and the growth of White snakeroot. She tested it out on a calf who indeed got the “trembles.” Others observed this connection too. But its link to milk-sickness and its threat was not taken seriously until the 1920s. Much of White snakeroot has been eradicated, but since it still volunteers, most milk we drink now gets pooled, that is, it comes from several different cows in order to dilute any tremetol. Pasteurization does not eliminate tremetol.

Common groundsel, Senecio vulgaris invades the ground speedily and weedily (see Q#2 for details) plus it gradually poisons man, horse and cow that consume it, with aptly named senecionine.

Common groundsel came to the U.S. from Eurasia, accidentally, probably mixed with wheat or hay seeds since it frequently grows in fertile fields of wheat and hay. The Pilgrims intentionally brought it here as early as 1620 as a reputed, albeit scientifically unlikely, remedy for early stage cholera, perhaps under the theory that “what doesn’t kill you makes you strong”. Not surprisingly it served as a purgative, emetic, and abortion inducer. It also served in poultices for chapped hands, for inflammations of skin and eye, for gouty feet, and as a remedy for epilepsy, jaundice, worms, toothache, red gums, and menstrual pain. However, its actual chemistry signals DANGER more than benefit. I’m glad I have better options due to the thoroughness of USDA testing of chemicals now and the need for approval before prescription.

4 Check the web for photos of it overshadowing tall guys in Poland and elsewhere.