WARNING: The Most Violently Toxic Plant in America Grows in Idaho

Whether I see them in the Boise Foothills or slithering along the Greenbelt, Idaho’s native snakes creep me out. 

I know that most of them are harmless, but there’s still something unsettling about spotting one slithering across the trail that I’m hiking. As it turns out, there’s something far more dangerous lurking in parts of Idaho. It doesn’t hiss. It doesn’t strike. All it does is sit there, looking like a harmless wildflower. However, it’s anything but that!

READ MORE: 3 Snakes You'll Meet in the Boise Foothills and Which One is Dangerous

The Most Poisonous Plant in America Can Be Found in Idaho

Meet Cicuta douglasii, better known as Western Water Hemlock. While it’s not particularly scary looking, the United States Department of Agriculture calls it the “most violently toxic plant that grows in North America.”

The department has included Western Water Hemlock in a pamphlet about poisonous plants of Southeast Idaho and the Idaho Mountain Express explains that it’s commonly found along small ditches and wet meadows in Blaine County.

As a member of the carrot family, it looks harmless. It’s also known to smell like carrots, which is why people may make the dangerous mistake of thinking it's a wild edible. 

Why Is Water Hemlock so Dangerous to Idaho Recreationists?

That mistake could be fatal, as the plant contains a substance called cicutoxin, a violent convulsant that’s most concentrated in the liquid you’ll find in the roots or oozing out of a broken stem. 

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The poisonous plant pamphlet says that you could exhibit symptoms of poisoning anywhere between 15 minutes to an hour after accidentally eating the plant. The symptoms are scary too. They include excessive salivation, frothing at the mouth, muscle twitching, vomiting, violent convulsions and “usually death.” 

Because the symptoms progress so rapidly, animals who consume it usually die. Luckily, if you can find emergency medical treatment quickly, doctors may be able to use drugs to prevent seizures in humans. They may also be able to help you breathe and prevent asphyxia, which is normally what kills animals that have been poisoned by Western Water Hemlock.  

Learn How to Identify the Western Water Hemlock in Idaho

The Backcountry Herbalist on YouTube did a very informative video on how to identify the plant, so if you have four minutes this video is worth checking out.

If you’re hiking, foraging or exploring with your kids and pets near streams or wet meadows, just do yourself a favor and steer clear of wild plants you’re unsure about. Don’t pick it. Don’t touch it. And whatever you do, don’t eat it!