About giant hogweed
Giant hogweed (Heracleum mantegazzianum) is a perennial herbaceous invasive plant that poses a severe human health risk. Originally from the Caucasus Mountains of western Asia, this plant has been cultivated in the United States, primarily as a curiosity, since the early twentieth century. Giant hogweed can grow up to 20 feet tall and has large umbrella-like flowers that bloom from mid-May to July. The sap of the plant can cause severe irritation, blistering, and burns to human skin when exposed to sunlight. Giant hogweed is on the federal noxious weeds list, which is intended to limit its spread. Giant hogweed has been found in a few Maryland counties since 2003 (Baltimore, Harford, and Garrett), but it is not common. There are several look-alike plants that are often mistaken for giant hogweed. Key characteristics for accurate identification of this plant are provided below.