Beware of Hogweed

In and out of water, invasive species are here to stay.

That’s what Dave Spann, district field manager for the Chautauqua County Soil and Water Conservation District, said about giant hogweed, which is making its way across the Northeast.

While other invasive species such as blue-green algae and water chestnuts have spread across ponds and lakes countywide, hogweed has been added to a list of on-land species.

“When they say ‘giant,’ it really is. Giant hogweed will be way over your head,” he said.

The plant is currently flowering and can grow to be 8-14 feet tall. It features large groups of small white flowers, a green stem with purple blotches and coarse white hairs. Leaves can grow up to 5 feet wide.

Countywide, there are 11 active hogweed sites.

According to the Department of Environmental Conservation, the plant’s sap, in combination with moisture and sunlight, can cause severe skin and eye irritation, painful blistering, permanent scarring and blindness.

Contact occurs either through brushing against the bristles on the stem or breaking the stem or leaves.

Should contact occur, wash the affected area immediately and keep it covered and out of sunlight.

“With no known natural predator or opposition in our environment, this weed has been causing significant damage to yards and parks, eroding soil and crowding out native plants,” said state Sen. Cathy Young, R-C-I-Olean. “Most alarmingly, however, is that contact with giant hogweed is also very harmful to people and animals, so look after your children and pets.”

Spann stressed the importance of keeping an eye out for the species.

“If you think you have the giant hogweed on your property, call the Department of Environmental Conservation, but do not touch it, not even with gloves,” he said, adding that two other plants look very similar. “Just stay away from it and call the DEC.”

Giant hogweed’s scientific name is Heracleum Mantegazzianum, and it originated in the Caucasus Mountain region between the Black and Caspian seas, according to the DEC website. Furthermore, it was introduced in the U.S. in the early 1900s as an ornamental garden plant and has been spreading across the Northeast ever since. The weed takes root in open sites with abundant light and moist soil, but can also grow in partially shaded habitats.

For help identifying the plant, email high resolution photos of the entire plant to or visit There is also a giant hogweed hotline, which can be reached at 1-845-256-3111.