Weed science Society of America Logo


Don’t Touch It: Invasive Plant With Sap That Can Cause Blindness Found in Virginia

Credit: www.washingtonpost.com

For weeks, Robert Emma wondered about the plants growing beside his new house. The flora, as many as 40 discrete plants, was “intimidating,” the amateur gardener said, with thorns and jagged leaves five feet wide. They stood taller — much taller — than a person, and cast a canopy of white blooms a yard wide.

“It definitely warrants a discussion, to say the least,” said Emma, of Berryville, Va. “If you saw this, you would think: ‘I’m not going to touch that.’ ”

This week, Emma’s instincts were proven right. He learned he is living beside a stand of giant hogweed, a toxic plant with sap that can cause burns and blindness, must be removed with protective gear and requires a permit to be moved across the state.

Mark Sutphin, an agricultural extension agent with Virginia Tech, said he wrangled a piece of Emma’s giant hogweed while wearing a Tyvek suit and goggles, then brought it back to the lab for identification.

“Don’t touch it,” he said. “Don’t cut it down unless you take extreme care.”

Emma’s plant, a notorious Virginia tier one noxious weed, is not alone in the commonwealth. Around the beginning of June, a Virginia Department of Transportation worker found another bunch of giant hogweed growing in Frederick County after quick-witted employees, recalling a U.S. Department of Agriculture warning about the plant some years ago, spotted it.

“Now that there’s a confirmed sighting, we need to be on the lookout,” said Ken Slack, a VDOT spokesman. “We have to make sure folks don’t get into it … don’t go after it like a weed.”

Though common in New York state, which has spent millions fighting the plant, and elsewhere in the Northeast, the giant hogweeds in Berryville and Frederick County are the plant’s first known locations in Virginia. The Berryville patch was planted by a previous owner, as the blooms, in a simpler time, were considered decorative.

Jordan Metzgar, a curator at Virginia Tech’s Massey Herbarium, helped identify Emma’s giant hogweed. He said the plant is easily mistaken for cow parsnips, but gardeners who aren’t sure what they’re looking at should back away and contact their local Virginia Tech agricultural extension agent or the Virginia Department of Agriculture and Consumer Affairs.

Though there’s no reason to think swarming hordes of giant hogweed will soon threaten Richmond or the Washington area, officials want to keep it contained. A single plant yields 20,000 seeds, which can be dispersed by winds over short distances. Seeds can also be inadvertently transported in soil.

Some jurisdictions aren’t taking any chances, sounding alarms about the effects of exposure.

“Skin reactions vary, but phytophotodermatitis can occur, meaning the sap makes the skin so sensitive to sunlight that … burns can occur from normal exposure to sun,” Isle of Wight County, near Norfolk, said in a statement. “Symptoms include painful blisters, which become darkly pigmented and can cause scars. Your skin can remain sensitive to sunlight for many years after exposure as well. And, if the sap gets in your eyes, there is the potential for blindness.”

Should one touch giant hogweed sap, it’s not quite as bad as touching the acidic blood of the titular creatures in the “Alien” franchise. There is hope.

“If you get exposed to it, best course of action to wash up with soap and water and stay out of sun,” Metzgar said. “Try to avoid light or tanning booths for the next couple days.”

The original news story can be found here.