CBSN

Why is hogweed so dangerous?

Though the giant hogweed plant looks appealing to the eye with a tall green stem and white flowers on top, it's not a plant you want to touch. Doing so could lead to serious health problems, including blindness. The plant was recently spotted in Calhoun County, Michigan, and authorities there are advising residents to take precautions.

"Hogweed has a toxic compound in it that is sun sensitive," medical contributor Dr. Holly Phillips told CBS News. "So if you get the sap on your skin or in your eyes and are then exposed to light, it can cause very serious reactions."

Though not as well known as poison ivy or poison oak, hogweed can be even more toxic. After touching hogweed, people can experience symptoms of severe burning and blistering on the skin, sometimes requiring a skin graft. If the sap gets into the eyes, it can cause long-term sunlight sensitivity and even blindness.

Hogweed can grow to 14 feet or more. It has long green stems with small red or purple spots and a spray of white flowers up top. "It's actually very pretty to look at," Phillips said.

In addition to the recent sighting in Michigan, giant hogweed has been found in New England, the Northwest, and the Mid-Atlantic region in the U.S. and is also very common in England. According to the New York State Department of Environmental Conservation, it grows along streams and rivers and in fields, forests, yards and roadsides. Though the plant prefers open areas with abundant sunlight and moist soil, it can grow in partially shaded areas, too.

If you see a giant hogweed plant, don't touch it. But if you realize you've come in contact with the plant, immediately wash the affected area with soap and water and stay out of the sun for 48 hours.

If you notice any rashes or blistering, see your doctor as soon as possible. "There are medications, both creams and oral medications you can take to lessen your reactions," Phillips said.

  • Ashley Welch On Twitter»

    Ashley Welch covers health and wellness for CBSNews.com