Lewis County Soil and Water Conservation District
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It may come as a surprise that a native plant to Western Asia has slowly made its way to Lewis County, New York. This Ornamental plant, called Giant Hogweed (Heracleum mantegazzianum), may appear alluring by its towering size. However, local residents should be cautioned of the dangers this plant can have to crops, local biodiversity and human health.

Giant Hogweed is known for its excessive height. It can grow to be fifteen feet tall. Hundreds of small white flowers combine to create large umbrella - like blooms. The stalk can be three to eight centimeters in diameter at the base, which is also noted for its purple speckles and hair sprouts. Giant Hogweed's compound leaves are deeply incised and grow to be over three feet in width. Giant Hogweed is often mistaken to for Cow Parsnip or Angelica.

This invasive species has numerous negative effects in the areas that it establishes itself in. Once Hogweed begins to grow, it quickly shades low-lying plants and thus decreases the biodiversity of a field, forested area, or ditch. In addition, Giant Hogweed has dangerous effects on humans after physical contact. Once the skin is exposed to the plant's sap and then exposed to sunlight or UV light, painful blisters form. When the blisters recede, they leave black and purple scars that can last for years. If the sap has contact with the eyes, it can cause temporary or even permanent blindness.

Giant Hogweed is considered a noxious weed by the USDA. Therefore, the public is not permitted to transport or move any portion of the plant.

If you have Giant Hogweed on your land or have seen Giant Hogweed in Lewis County, please contact our office.

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Lewis County Soil and Water Conservation District, 5274 Outer Stowe Street, Suite #1 Lowville, NY 13367 | Phone: (315) 376-6122