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There’s a Plant Called ‘Giant Hogweed’ and It Can Cause Blindness and Third Degree Burns

Giant hogweed, also known as giant cow parsnip.Brent Lewis—The Denver Post via Getty Images

Ever hear the one about the humongous plant that can potentially cause blindness and third degree burns?

It’s no joke. There’s a plant called “giant hogweed” (also known by other deceivingly quaint names like giant cow parsnip, hogsbane, and cartwheel-flower) with toxic sap that can be extremely harmful to the skin and eyes when combined with sunlight. And the invasive species, which can grow to 20 feet tall with leaves that are five feet across, has reportedly been found in Virginia for the first time.

“Giant Hogweed makes Poison Ivy look like a walk in the park. Contact with this plant, combine [sic] with exposure to the sun, can produce 3rd degree burns and permanent blindness,” wrote the Isle of Wight County of Virginia in a Facebook post last week. Isle of Wight is located near the Hampton Roads are of Virginia, to the west of Norfolk.

**Safety Alert**Giant Hogweed reportedly found in VirginiaIf you have never heard of Giant Hogweed, you’re not alone!…

Posted by Isle of Wight County Virginia on Wednesday, June 13, 2018

Local residents are being urged to report any hogweed sightings to the Virginia Invasive Species website.

The sap of giant hogweed, found in its stem, contains toxic chemicals called “furanocoumarins.” These are the substances that make the weed so dangerous. “When [furanocoumarins] come into contact with the skin, and in the presence of sunlight, they cause a condition called phyto-photodermatitis: a reddening of the skin, often followed by severe burns and blistering,” according to Great Britain’s GB Non-native Species Secretariat (hogweed is a huge problem in the U.K.). “The burns can last for several months and even once they have died down the skin can remain sensitive to light for many years.”

Blindness can occur if the sap manages to get into the eyes.

If you do come across giant hogweed in the wild, don’t touch it—and don’t try to chop it down using a weed wacker, as that could potentially spread the sap around. Instead, document it and report it to local environmental authorities.

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