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 Health Hazards & Safety Instructions for Giant Hogweed (with graphic photos) 
 
 When giant hogweed (GH) sap, which contains photosensitizing furanocoumarins, contacts human skin in conjunction with sunlight, it can cause phytophotodermatitis - a serious skin inflammation. Hogweed warning sign in Ontario, Canada (Gavin Edmonstone/Flickr/CC BY-NC 2.0) 
 
 Once you have an infestation, it takes a lot of work to control the giant hogweed to prevent its spread, as its seeds - each plant can shed thousands - remain viable in the soil for several years. Check the site and surrounding areas for the next several years for the emergence of any hogweed seedlings or regrowth from previous year's plants."
– What ScienceAlert calls a "giant horror plant" has made its way to yet another US state, and people who come in contact with it could feel the pain. Virginia Tech's Massey Herbarium tweeted last week it had IDed a giant hogweed (aka Heracleum mantegazzianum) plant in Clarke County, later updating that count on Facebook to 30 plants. The plant holds what Fox News deems a "toxic sap," which prevents human skin from protecting itself from the sun's rays, leading to severe burns that can be worsened by sweat. New York state's Department of Environmental Conservation lists other hazards that can result from coming in contact with the plant (as well as some photos of terrible burns), including long-term sunlight sensitivity, oozing blisters, scarring, and even permanent blindness if the sap makes its way into one's eyes. And it doesn't take a lot to fall prey to the poison of the giant hogweed, which resembles an umbrella or mushroom made up of white flowers: A simple brush up against its bristles can spur a reaction as soon as 15 minutes later, with "sensitivity peak between 30 minutes and two hours after contact," per the DEC. It's difficult to stop the spreading of the invasive plant, which is native to the Caucasus region near Russia and was introduced to the US sometime in the early 20th century. Virginia environmental officials are warning the plant may have been spotted in other parts of the state and for people who come across it to not let their bare skin make contact. It also offers a guide for very carefully getting rid of the plant. (Giant hogweed has been found in at least a dozen other states.)