The tallest poison ivy in the world is in Ontario, says Guinness | CBC Radio

When Robert Fedrock first happened upon what is now a Guinness World Record-holding poison ivy, he wasn’t quite sure what he was looking at.

“The vine is so big that, at eye level, it really just looks like a hairy creature from Stranger Things,” Fedrock told As It Happens host Nil Köksal. 

But when he looked up — way up — he saw the tell-tale three-leaf green foliage of a poison ivy, climbing up a white ash tree. 

It was, by far, the tallest  poison ivy he’d ever encountered in the wooded area on his farm in Paris, Ont., where he spends a lot of time walking and observing nature. And, according to Guinness, it’s the tallest one on record anywhere in the world as of March 12.

The plants tend to grow between 60 to 90 centimetres, according to the Ontario government. But surveyors measured this one at 20.75 metres, which Guinness notes is the length of two school buses. 

“We didn’t use school buses to measure it, but that would be a fair representation,” Fedrock said.

As its name suggests, poison ivy produces an oily sap that is poisonous to the touch, usually leaving those who interact with one with a nasty rash.

Fedrock was clearing a walking path through the brush when he discovered the poisonous plant. And he did, indeed, have a reaction to it — though he insists it was “not that bad.” 

“It kind of compared to a whole bunch of mosquito bites,” he said. 

The plant’s poisonous properties might compel some people to have it removed from their land. But Fedrock wouldn’t conceive of it.

“I think it’s a majestic plant. I think it’s beautiful,” he said. “I think cutting it down would be, yeah, a horrible thing to do.”

Dangerous — but important

Poison ivy is a native species in Ontario and it plays an important role in the ecosystem, providing a food source for local wildlife, says biologist Brendon Samuels, a PhD student at Western University in London, Ont., with a penchant for indigenous plant life.

While ivy can grow to huge lengths under optimal conditions, he says it’s rare to find one this big.

“Poison ivy, despite being native, is a noxious weed, and so it is managed in a lot of areas. People see poison ivy growing, they’ll tend to come in and remove it with herbicides and stuff,” he told CBC. 

He says it’s a rare treat to see a poison ivy that’s been left alone to thrive. 

“You wouldn’t want something like this poison ivy plant growing in a park, for example. But it should exist,” he said. 

“It’s indigenous. It evolved here. And so the fact that it has a space that it can thrive … I think it just underscores the importance of those natural areas.”

Probably not really the tallest 

While the Paris ivy is the tallest ever recorded by Guinness, neither Fedrock nor Samuels believe it’s actually the tallest in the world.

In fact, Samuels says he once found one in Melbourne, Ont., that rivals Fedrock’s.

Fedrock, however, is not threatened. He says he reported the plant to Guinness in the hopes it would inspire people to beat his record.

“I think having people looking for taller ones would be great,” he said. “The more people know about plants around them, you know, the more respect they have for the environment and more interest they’ll have in it.”

If you do find one, Samuels recommends snapping a picture from a safe distance, and uploading it to a nature tracking app like iNaturalist so scientists and local authorities have a record of it. 

But just look, he said — don’t touch.

“It’s a good reminder also that when in a natural area … don’t deviate from the trails because you could be putting yourself at risk.”