Expert says 2020 derecho may have helped poison hemlock thrive in new places

CEDAR RAPIDS, Iowa (KCRG) – Poisonous plants are continuing to spread in the state of Iowa.

Last summer, TV9 brought you a story about poison ivy and poison hemlock spreading in eastern Iowa.

A year later, an expert with Iowa State University says there are a variety of things causing poison hemlock to spread.

The plant with the white flower on top looks pretty unassuming.

“It looks a little bit like Queen Anne’s Lace,” said Shelly Wilson. Wilson was enjoying the Freedom Festival in Cedar Rapids this weekend with her friends when TV9 asked if she’d ever heard of Poison Hemlock.

“I have never heard of it, it’s always good to be aware,” said Donna Moeller, Wilson’s friend.

“I had never heard of it either,” Wilson added.

Experts at Iowa State University say the plant is highly toxic to people and animals and can be deadly if ingested.

“One of the problems with poison hemlock is that it can look like some species that are edible,” said Meaghan Anderson, a field agronomist at ISU.

Anderson says these dangerous weeds may be popping up in more places than they used to for a variety of reasons, including the 2020 derecho.

“It didn’t physically move these plants anywhere that they weren’t already. I think that’s fairly unlikely,” said Anderson. “I think what the derecho probably did do was it opened up a lot of what was historically good tree cover under fairly full shade, and perhaps provided lots of species, including poison hemlock, a little bit more of a niche where it got more sunlight and more opportunity for some of these invasive species that we think of like our bush honeysuckle type species, poison hemlock, poison ivy, garlic mustard, all kinds of these species we know we don’t like to see on the edges of woodlands or within woodlands, but it probably provided them with a pretty good opportunity to get better established than they would have if there was full canopy cover in these tree areas.”

Another way the plant spreads is through the movement of soil caused by human activity.

“We’re really effective as people in building things and expanding things and we move a lot of stuff around on equipment, so I do imagine that’s helping it a bit,” Anderson said.

The weed is commonly found along the edges of woodlands, fence lines, and crop fields, and is becoming increasingly common in ditches alongside roads.

If it pops up on your property, you can remove it yourself, just use caution. Wearing gloves is recommended.

“You can dig up those giant plants right now. Given the fact that they’re basically all flowering everywhere, I probably wouldn’t just lay it down on the landscape and leave it to rot, I would probably dispose of it as trash this time of year,” Anderson said.

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