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Avoid The Giant Hogweed, It’s Highly Toxic

Identifying Toxic Plants

Heracleum mantegazzianum, or ‘Giant Hogweed‘, is a tall herbaceous plant which can grow to over 14 feet tall, and 5.5 feet wide. It is a member of the carrot family (Apiaceae), and the diameter of its stem is 2 to 4 inches.

This herb invades various locations, and it will cause extensive skin damage if you do so much as touch it. It can also cause blindness. If you accidentally come into contact with it, stay out of sunlight until you see a physician. They will advise you on how to proceed.

This tall, menacing plant has umbrella-shaped flower clusters on top which will help you to distinguish it from the apparently similar Cow Parsnip plant, which has flat-topped flower clusters, as opposed to the umbrella shape. The Cow Parsnip plant’s flower clusters are up to 1 foot wide, while the Giant Hogweed‘s flower clusters grow up to 2.5 feet wide.

In the United States, it was actually introduced as a garden ornament!

According to the New York State Department of Environmental Conservation:

Giant Hogweed is a native of the Caucasus Mountain region between the Black and Caspian Seas. It was introduced to Europe and the United Kingdom in the late nineteenth century and to the United States in the early twentieth century as an ornamental garden plant. It has become established in New England, the Mid-Atlantic Region and the Northwest. Giant Hogweed grows along streams and rivers and in fields, forests, yards and roadsides. It prefers open sites with abundant light and moist soil but it can grow in partially shaded habitats, too. The map to the right displays the current confirmed locations of giant Hogweed sites in New York State.

Read more about how to identify this plant from the source.

The flowerhead of the Cow Parsnip plant. Image Credit: NYS Dept. Of Environmental Conservation.
The flowerhead of a Cow Parsnip plant. Image Credit: NYS Dept. Of Environmental Conservation.
The flowerhead of a Giant Hogweed.

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