Invasive Plant: Giant Hogweed--Where Is It Not Established?

In the UK, a 10-year-old girl fishing with her father recently took home a stalk from a highly invasive plant, the giant hogweed, and developed serious burns and blisters on her hands, as the Express reported. Several states, including New York and Massachusetts, recently issued fact alerts about the weed, Heracleum mantegazzianum, and it is established in the Mid-Atlantic, New England, and the Northwest. The plant's sap, in combination with sunlight and moisture, can cause burns and blisters, along with permanent scarring or even blindness.

Hogweed can grow to 14 feet and has hollow, ridged stems that grow 2-4 inches in diameter and have dark reddish-purple blotches. Its compound leaves can be up to 5 feet wide, according to the New York state website.

The plant is a federally listed noxious weed. It was introduced to this country in the early twentieth century as a garden plant. Originally, the weed is from the Caucasus Mountains, between the Black and Caspian Seas. This large plant thrives along streams and rivers and in fields, forests, yards and roadsides. It is particularly found in open sites with bright light, but can grow in partially shaded areas too.

If you come in contact with the weed, immediately wash the affected area with soap and water--and keep it away from sunlight for 48 hours. You should also see your doctor if you think you've been burned by the plant.

A giant hogweed identification page is here.

The USDA has info here.