Top Five Poisonous Plants to Be Aware Of (in the Upper Midwest)

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Poisonous Plant Panic

One of the most common questions I get asked as a professional foraging instructor is “How do you not kill yourself?” The implication here is that foraging is a dangerous activity and I could suddenly die by accidentally ingesting a poisonous species—a commonly held misbelief that I do my best to assuage.

However, that is not to ridicule or condemn people who hold that fear. I remember that I felt similarly when I first started foraging over twenty years ago. Back then, we didn’t have all the great resources we do now, and foraging guides (in my opinion) often over-emphasized the danger of mistaking an edible species for a similar-looking poisonous one. In fact, still to this day, many resources make foraging sound like a risky endeavor, suitable only for grizzled woodsfolk, or otherwise expert botanists or mycologists with fancy degrees.

However, I’m here to tell you that’s not the case! And I firmly believe that learning poisonous species before or while learning edible and medicinal ones greatly increases your identification skills while reducing your anxieties.

Poisonous Plant Pals Webinar

Just in time for the foraging season, I have a live webinar coming up to teach you about common poisonous plants and mushrooms! The focus will be on Minnesota species, though most folks living in the eastern and central regions of the US and Canada will benefit from this knowledge. We will discuss identification and toxicity, and go over edible species that are considered “look-alikes.” Covered species will include poison hemlock, water hemlock, poison ivy, destroying angel, deadly galerina, and more. I hope to see you there!

Top Five Poisonous Plants to Be Aware Of (in the Upper Midwest)

In the meantime, here is my top five list! What did I miss? Are there any that you would have included instead? Let me know in the comments below!

Water hemlock (Cicuta maculata)

Water hemlock is widely considered to be the most deadly poisonous plant in North America. There are many documented fatalities, owing partially to its plump roots with carrot-like scent and its resemblance to water parsnip (Sium suave) and other edible members of the carrot family. All parts are poisonous due to the presence of cicutoxin, a powerful neurotoxin that causes nausea, vomiting, stomach pain, tremors, seizures, and death by respiratory paralysis.

Water hemlock can be identified by its white compound umbels, basal and alternate leaves that are 2-3 times compound, and the relatively unique feature of having leaf veins that terminate in the notch of the teeth (rather than the tips.)

Water Hemlock Identification→

Poison hemlock (Conium maculatum)

Poison hemlock is another deadly plant in the carrot family with numerous documented deaths. All parts are poisonous, including the powder on the surface. Wash hands after handling. Poison hemlock contains toxic alkaloids, which in cases of acute poisoning cause central nervous system suppression, kidney failure, slowed heartbeat, and respiratory paralysis. This plant can be confused with wild carrot (Daucus carota) and other edible members of the carrot family. Thankfully, its foul smell warns off most would-be consumers.

Poison hemlock can be identified by its white compound umbels; basal and alternate leaves that are 2-3 compound with finely divided, fern-like leaflets; and hairless purple-spotted stem.

Poison Hemlock Identification→

Western & Eastern Poison Ivy (Toxicodendron rydbergii & T. radicans)

Fortunately, poison ivy is not often consumed, but it still poses a danger to foragers due to the contact dermatitis it causes in sensitive individuals. Sensitivity to the oil varies, but an allergic reaction may be acquired with repeated contact in “immune” individuals. Direct or indirect contact with bruised leaves or other parts of the plant produces a rash. It can be dangerous to handle clothing, pets, tools, or other articles that have bruised the plant. It’s also dangerous to walk through or breathe in smoke from burning these plants.

There are two species of poison ivy in the US and Canada. Western poison ivy (which is more common in Minnesota) typically grows as small shrub 1-2 feet tall. Eastern poison ivy is either more branching or vining than it’s westerly sibling. Both species have leaves compound in groups of three, oval or egg-shaped, pointed at the tip, toothless or with coarse teeth; fruit is a small green berry turning dull white to yellowish.

Poison ivy could be mistaken for fragrant sumac (Rhus aromatica), but the fruits of this plant are red and fuzzy at maturity, unlike the hairless and whitish fruits of poison ivy.

Western Poison Ivy Identification→

Eastern Poison Ivy Identification→

Canada Yew (Taxus canadensis)

This evergreen shrub is native to eastern North America, but non-native cultivars are often planted as hedges in yards and in front of businesses. All members of the genus share similar identification characteristics and toxic traits.

All parts of yew are poisonous, except the flesh of the fruit, which is edible. However, the seed within the fruit contains the highest concentration of toxins! The plant contains taxine, a rapidly absorbed cardio-depressant that can kill within a few hours of ingestion in cases of acute poisoning. Death may take as long as 24 to 48 hours if smaller amounts were consumed.

Yew can be mistaken for edible coniferous evergreens, though the red fruits are a giveaway to the genus. Fir species (Abies spp.) are most likely to pose some confusion, as both firs and yews have flat needles that appear to grow in two rows. However, the similarities pretty much end there—yew needles have sharp-pointed tips, while those of fir are blunt or notched. Furthermore, firs produce cones that stand upright on the twig, not red berry-like fruits.

Canada Yew Identification→

More Information About Yew→

Red & White Baneberry (Actaea rubra & A. pachypoda)

Red and white baneberry are two closely related plants that are native to the rich woodlands of North America. They look very similar and are difficult to distinguish from each other when not fruiting. To further confusion, both plants can produce red or white berries. Red baneberry has slender green flower/fruit stalks. White baneberry has thick stalks, which are light green when flowering and turning red after fruiting. Leaves for both species are 2 or 3 times compound, in groups of 3 or 5.

All parts are presumed to be toxic, though the exact compound remains unidentified. The berries and roots are especially toxic. Fortunately, the berries are reportedly very bitter, so it is unlikely that they would be eaten in large enough quantities to cause serious harm. Symptoms of baneberry poisoning include vomiting, delirium, stomach cramps, and cardiac suppression. There are no reported deaths in North America, and they are not likely to be mistaken for any edible fruit in this region.

Red Baneberry Identification→

White Baneberry Identification→

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