Did you know that there is a plant that can cause burns and permanent blindness? Yes, there is... and it's called Giant hogweed, or Heracleum mantegazzianum. Basically, it looks like an old, regular plant. But beware, this plant is actually dangerous than you thought.
Giant hogweed is a large, flowering, perennial plant, and is native to the Caucasus Mountain region in Asia. It is a tall plant with white flowers in umbrella-like clusters, lobed leaves, and stems covered in purplish-red spots. This can grow up to 14 feet tall and you'll find it in forests, yards, fields, and roadsides.
Giant hogweed can live for decades and have long taproots that make them especially hard and difficult to remove. You cannot easily identify this plant because it can be confused with other flowering plants such as the Queen Anne's Lace – beautiful, harmless, and can be found in wedding bouquets and roadsides near you.
The plant was introduced as a garden plant in the United States in the early 1900s. This is an invasive species where it grows in parts of Washington, Oregon, Michigan, Wisconsin, New Jersey, Pennsylvania, Vermont, and New York. The federal government considered the giant hogweed as a noxious weed – meaning it is illegal to transport across state lines without a permit.
How dangerous is giant hogweed?
Giant hogweed produces a toxic sap full of photosensitizing furanocoumarins. These are organic chemicals that can do some dangerous and serious damages. According to the New York State Department of Environmental Conservation (NYSDEC), the sap can cause severe irritation, burns, and blisters (also called phytophotodermatitis) when it makes contact with the skin combined with sunlight.
The sap basically makes the skin photosensitive, and the sunlight causes a third-degree burn – the most serious type of burn. The irritation could be worse when there is moisture, such as sweat on the skin or dew on the plant.
The skin reaction starts 15 minutes after exposure. The painful blisters form about 48 hours, and can then become pigmented and scab over. The scars can heal for about weeks, while the burns can last for more than months or even years. When the skin reaction starts, use painkilling creams, topical steroids, or calamine lotion to ease discomfort and inflammation.
Aside from the skin damage, the sap can also burn in the cornea and permanent blindness when it gets to the eyes. If the sap gets in your eyes, wash them out immediately and wear sunglasses.