Giant Hogweed, Heracleum mantegazzianum, a highly dangerous Class A Noxious Weed was recently discovered in Kelso. It is the first documentation of this Class A species in Cowlitz County. Giant Hogweed is a public safety hazard containing a clear sap that sensitizes skin to ultraviolet radiation. Effects can be delayed and are activated by exposure to sunlight, leading to severe skin burns, blistering and painful dermatitis. The sap may injure people and animals and can transfer from animals to people. Giant Hogweed can also form dense infestations outcompeting other desirable plants.